{"title":"Bioconjugation \u0026 Click Chemistry","description":"\u003cdiv style=\"max-width:700px;font-family:Georgia,serif;color:#222;margin-bottom:32px;\"\u003e\n\n  \u003cdiv style=\"background:#002147;border:1px solid #002147;border-radius:8px;padding:16px 20px;margin-bottom:20px;\"\u003e\n    \u003cp style=\"margin:0 0 6px 0;font-size:13px;letter-spacing:0.08em;text-transform:uppercase;color:#7fa8cc;\"\u003eCatalogue\u003c\/p\u003e\n    \u003cp style=\"margin:0 0 12px 0;font-size:22px;font-weight:bold;color:#ffffff;\"\u003eBioconjugation \u0026amp; Click Chemistry\u003c\/p\u003e\n    \u003cp style=\"margin:0;font-size:15px;line-height:1.7;color:#ffffff;\"\u003eHigh-purity reagents for the selective, covalent modification of proteins, peptides, and oligonucleotides. Copper-free click chemistry, bioorthogonal tetrazine ligation, native chemical ligation, and antibody–drug conjugate linkers — supplied at research grade for clean, chemoselective bioconjugation in living systems.\u003c\/p\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv style=\"display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-bottom:20px;\"\u003e\n    \u003cdiv style=\"background:#e8e7e2;border:1px solid #c8c7c2;border-radius:8px;padding:16px;\"\u003e\n      \u003cp style=\"margin:0 0 6px 0;font-size:11px;letter-spacing:0.08em;text-transform:uppercase;color:#999;\"\u003eApplications\u003c\/p\u003e\n      \u003cp style=\"margin:0;font-size:13px;color:#555;line-height:1.9;\"\u003eProtein and antibody labelling\u003cbr\u003eAntibody–drug conjugate synthesis\u003cbr\u003eChemical and native ligation\u003cbr\u003eBioorthogonal labelling in live cells\u003cbr\u003eActivity-based protein profiling\u003c\/p\u003e\n    \u003c\/div\u003e\n    \u003cdiv style=\"background:#e8e7e2;border:1px solid #c8c7c2;border-radius:8px;padding:16px;\"\u003e\n      \u003cp style=\"margin:0 0 6px 0;font-size:11px;letter-spacing:0.08em;text-transform:uppercase;color:#999;\"\u003eEvery shipment includes\u003c\/p\u003e\n      \u003cp style=\"margin:0;font-size:13px;color:#555;line-height:1.9;\"\u003eBatch-specific CoA\u003cbr\u003eSDS — EU CLP\/GHS compliant\u003cbr\u003eCommercial invoice\u003cbr\u003eDDP service available worldwide\u003cbr\u003eShipped from Helsinki, Finland\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cp style=\"font-size:12px;color:#888;line-height:1.6;\"\u003eAll products are Research Use Only (RUO). Not for use in humans or animals, and not for diagnostic, therapeutic, or clinical applications.\u003c\/p\u003e\n\n\u003c\/div\u003e\n","products":[{"product_id":"nhs-cas-6066-82-6","title":"NHS | CAS 6066-82-6 | ≥98%","description":"\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eTechnical Specifications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; font-size: 0.95em; border: 1px solid #e4e8f0; border-top: none; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eCAS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e6066-82-6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eEC \/ EINECS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e228-001-3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMDL Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eMFCD00005516\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSMILES\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eC1CC(=O)N(C1=O)O\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChI\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eInChI=1S\/C4H5NO3\/c6-3-1-2-4(7)5(3)8\/h8H,1-2H2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChIKey\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eNQTADLQHYWFPDB-UHFFFAOYSA-N\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePubChem CID\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e80170\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Formula\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eC₄H₅NO₃\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Weight\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e115.09 g\/mol\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMelting Point\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e95–98 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSolubility\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eSoluble in water, ethanol, DMF, DMSO, acetone; sparingly soluble in diethyl ether\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePurity\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e≥98%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePhysical Form\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eWhite crystalline powder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eHS Code\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e2925.19\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eShelf Life\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eRetest period: 36 months from date of manufacture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eStorage Conditions\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eStore in a cool, dry place in a tightly sealed container protected from moisture. Midly hygroscopic\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eProduct Description \u0026amp; Scientific Applications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"padding: 16px 20px; border: 1px solid #e4e8f0; border-top: none; font-family: Georgia, 'Times New Roman', serif; font-size: 0.95em; line-height: 1.65; color: #333;\"\u003e\n\u003cp\u003e\u003cstrong\u003eNHS (N-hydroxysuccinimide; 1-hydroxypyrrolidine-2,5-dione; HOSu)\u003c\/strong\u003e is a classic active-ester additive in amide-bond formation and bioconjugation chemistry. Paired with a carbodiimide such as EDC or DCC, it converts a carboxylic acid into a stable, amine-reactive NHS ester: the carbodiimide first forms a short-lived O-acylisourea, which NHS intercepts before hydrolysis or rearrangement to the unreactive N-acylurea. The NHS ester is more stable than that intermediate, crystalline and isolable when prepared dry, yet still reactive toward primary amines. It acylates lysine ε-amines and N-terminal α-amines of proteins at physiological to mildly alkaline pH (≈ 7.2–9.0), forming stable amide bonds; ester hydrolysis competes with aminolysis, so coupling efficiency depends strongly on pH and water exposure. In peptide synthesis, NHS esters are valued as active esters that form amide bonds with low racemisation at the α-carbon. EDC\/NHS is a standard activation system for aqueous carboxyl-to-amine bioconjugation. NHS is supplied as a white to almost white crystalline solid, soluble in water, DMF and DMSO, and should be kept dry.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCarbodiimide-mediated amide-bond formation\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWith EDC or DCC, NHS traps the O-acylisourea before hydrolysis or N-acylurea formation, diverting the activated acid into an NHS ester and improving productive amide formation.\u003c\/li\u003e\n\u003cli\u003eThe NHS ester acylates primary amines under mild, near-neutral to slightly alkaline conditions (pH ≈ 7.2–9.0), giving stable amide bonds.\u003c\/li\u003e\n\u003cli\u003eEDC\/NHS suits aqueous and semi-aqueous media, while DCC\/NHS handles water-insoluble substrates in organic solvent; pre-forming the NHS ester separates carboxyl activation from the subsequent amine-coupling step.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eBioconjugation, labelling and protein modification\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eAmine-reactive NHS esters of fluorescent dyes, biotin, PEG and ADC linker\/payload reagents acylate solvent-accessible lysine ε-amines and N-termini of antibodies and other proteins — core chemistry for antibody labelling, protein modification and lysine-based antibody–drug conjugate assembly.\u003c\/li\u003e\n\u003cli\u003eCouplings run in mild aqueous buffer, commonly bicarbonate or phosphate near pH 8 — conditions mild enough to preserve the structure and activity of many folded proteins.\u003c\/li\u003e\n\u003cli\u003eBecause the N-terminal α-amine is less basic than the lysine ε-amine, lower labelling pH can bias acylation toward the N-terminus, giving partial site selectivity rather than true single-site modification.\u003c\/li\u003e\n\u003cli\u003ePre-formed NHS esters are crystalline, isolable dry reagents and are supplied as ready-to-use amine-reactive dye, biotin and PEG derivatives.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eSurface functionalisation and biosensors\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEDC\/NHS activation of carboxylated surfaces — carboxymethyl-dextran hydrogels used in Biacore CM-series chips or 11-mercaptoundecanoic-acid self-assembled monolayers — is the predominant covalent amine-coupling route for immobilising protein ligands on SPR and related optical biosensors.\u003c\/li\u003e\n\u003cli\u003eThe same activation functionalises carboxylated microarray slides, nanoparticles and microfluidic surfaces through stable amide linkages.\u003c\/li\u003e\n\u003cli\u003eSulfo-NHS, the sulfonated water-soluble analogue, improves EDC-mediated coupling on fully aqueous platforms by forming water-soluble amine-reactive esters; remaining activated surface esters are capped with ethanolamine after ligand immobilisation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCrosslinking and structural biology\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eHomobifunctional NHS-ester crosslinkers — DSS and its water-soluble analogue BS3 — bridge proximal lysine ε-amines across an 11.4 Å spacer, capturing protein–protein contacts and stabilising assembled complexes.\u003c\/li\u003e\n\u003cli\u003eHeterobifunctional reagents such as sulfo-SMCC carry an NHS ester at one end and a maleimide at the other, joining a protein amine to a second molecule's thiol in a controlled, two-step sequence that limits self-conjugation.\u003c\/li\u003e\n\u003cli\u003eAmine-reactive NHS-ester crosslinkers — BS3, DSS and MS-cleavable analogues such as DSSO and DSBU — are principal reagents in XL-MS, where lysine–lysine distance restraints support cryo-EM interpretation and computational modelling of complex architecture.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFurther Reading\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor guidance on selecting between carbodiimides, aminium\/uronium salts, phosphonium salts and other reagent classes for amide and peptide bond formation, see NorrChemica's Lab Journal guide: \u003ca href=\"https:\/\/www.norrchemica.com\/blogs\/lab-journal\/choosing-a-coupling-reagent-for-amide-and-peptide-bond-formation\"\u003eChoosing a Coupling Reagent for Amide and Peptide Bond Formation\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eShipping Destinations\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e4e8f0; border-top: none; padding: 12px 16px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.95em;\"\u003e\u003cul style=\"margin: 0; padding: 0; list-style: none;\"\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEU \u0026amp; UK: Priority delivery, 2–5 business days.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eUnited States (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEFTA Countries (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eWorldwide: 7–14 business days, selected locations.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"NorrChemica™","offers":[{"title":"25 g","offer_id":53490783912273,"sku":"NOR-6066826-25g","price":27.0,"currency_code":"EUR","in_stock":true},{"title":"50 g","offer_id":53490783945041,"sku":"NOR-6066826-50g","price":35.0,"currency_code":"EUR","in_stock":true},{"title":"100 g","offer_id":53490783977809,"sku":"NOR-6066826-100g","price":49.2,"currency_code":"EUR","in_stock":true},{"title":"250 g","offer_id":53490784010577,"sku":"NOR-6066826-250g","price":73.2,"currency_code":"EUR","in_stock":true},{"title":"500 g","offer_id":53490784043345,"sku":"NOR-6066826-500g","price":98.0,"currency_code":"EUR","in_stock":true},{"title":"1 kg","offer_id":53490784076113,"sku":"NOR-6066826-1000g","price":159.2,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/6357\/1793\/files\/NHS_NORRCHEMICA_MULTILISTING_98__VR.png?v=1780589264"},{"product_id":"ptad-cas-4233-33-4","title":"4-Phenyl-1,2,4-triazoline-3,5-dione (PTAD) | CAS 4233-33-4 | ≥95%","description":"\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eTechnical Specifications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; font-size: 0.95em; border: 1px solid #e4e8f0; border-top: none; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eCAS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e4233-33-4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eEC \/ EINECS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e224-191-7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMDL Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eMFCD00003148\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSMILES\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eC1=CC=C(C=C1)N2C(=O)N=NC2=O\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChI\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eInChI=1S\/C8H5N3O2\/c12-7-9-10-8(13)11(7)6-4-2-1-3-5-6\/h1-5H\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChIKey\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eISULLEUFOQSBGY-UHFFFAOYSA-N\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePubChem CID\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e77913\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Formula\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eC₈H₅N₃O₂\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Weight\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e175.14 g\/mol\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMelting Point\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e168–175 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSolubility\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eSparingly soluble in chloroform; slightly soluble in ethyl acetate and methanol; workable in THF under synthetic conditions; very slightly soluble in water.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePurity\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e≥95%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePhysical Form\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eRed to dark red crystalline powder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eHS Code\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e2933.99\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eShelf Life\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eRetest period: 36 months from date of manufacture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eStorage Conditions\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eStore refrigerated (2–8 °C) in a tightly sealed container under inert atmosphere, protected from moisture and light\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eProduct Description \u0026amp; Scientific Applications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"padding: 16px 20px; border: 1px solid #e4e8f0; border-top: none; font-family: Georgia, 'Times New Roman', serif; font-size: 0.95em; line-height: 1.65; color: #333;\"\u003e\n\u003cp\u003e\u003cstrong\u003eHetero-Diels–Alder reactions\u003c\/strong\u003e — PTAD (4-phenyl-1,2,4-triazoline-3,5-dione), also known as the Cookson reagent, is one of the most powerful dienophiles known in organic chemistry. It reacts with conjugated dienes in [4+2] cycloaddition reactions at room temperature within seconds, often quantitatively, to give stable urazole-containing Diels–Alder adducts. This exceptional reactivity arises from the low-lying LUMO of the azo N=N bond flanked by two electron-withdrawing carbonyl groups. PTAD is the reagent of choice when rapid, clean trapping of diene intermediates is required under mild conditions (Cookson, R. C.; Gilani, S. S. H.; Stevens, I. D. R. J. Chem. Soc. C 1967, 1905).\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eVitamin D₃ chemistry — diene protecting group\u003c\/strong\u003e — PTAD is widely used as a protecting group for the s-cis-diene system of vitamin D₃ (cholecalciferol) and its metabolites. The PTAD–vitamin D adduct is stable to chromatographic purification, chemical modification at other sites, and prolonged storage. Removal of the PTAD group regenerates the diene under mild conditions. This strategy is essential in the synthesis and analytical characterisation of vitamin D metabolites including 1α,25-dihydroxyvitamin D₃ and 25-hydroxyvitamin D₃ (Windaus, A.; Linsert, O. Justus Liebigs Ann. Chem. 1928, 465, 148; Holick, M. F. et al. Biochemistry 1971, 10, 2799).\u003cstrong\u003eAnalytical derivatisation of vitamin D\u003c\/strong\u003e — PTAD is the standard derivatisation reagent for the quantification of vitamin D₂ and D₃ metabolites by LC-MS\/MS in clinical and food analysis. The PTAD adduct enhances ionisation efficiency and chromatographic separation, enabling detection of vitamin D metabolites at sub-nanomolar concentrations in serum and biological matrices. This application makes PTAD an essential reagent in clinical biochemistry laboratories worldwide.\u003cstrong\u003ePrismane synthesis\u003c\/strong\u003e — the first successful synthesis of prismane (tetracyclo[2.2.0.0²,⁶.0³,⁵]hexane) was achieved in 1973 using PTAD as a key reagent to trap the benzvalene–cyclopentadiene Diels–Alder adduct, demonstrating the reagent’s ability to capture highly strained and transient diene intermediates (Katz, T. J.; Acton, N. J. Am. Chem. Soc. 1973, 95, 2738).\u003cstrong\u003eEne reactions\u003c\/strong\u003e — PTAD undergoes ene reactions with isolated alkenes bearing allylic hydrogens, providing a mild method for C–N bond formation. This reactivity complements its Diels–Alder chemistry and has been exploited for the functionalisation of terpenes, steroids, and other natural products containing trisubstituted alkenes.\u003cstrong\u003eThiol oxidation to disulfides\u003c\/strong\u003e — PTAD selectively oxidises thiols to symmetric disulfides under mild conditions without over-oxidation to sulfoxides or sulfones. This makes it a useful reagent for disulfide bond formation in peptide chemistry and protein biochemistry, where controlled oxidation is critical for maintaining native folding.\u003cstrong\u003eRetro-Diels–Alder studies\u003c\/strong\u003e — PTAD adducts serve as substrates for studying thermal and photochemical retro-[4+2] reactions. The well-defined stereochemistry and stability of PTAD cycloadducts make them ideal model systems for investigating the orbital symmetry rules governing electrocyclic and cycloaddition processes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eShipping Destinations\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e4e8f0; border-top: none; padding: 12px 16px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.95em;\"\u003e\u003cul style=\"margin: 0; padding: 0; list-style: none;\"\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEU \u0026amp; UK: Priority delivery, 2–5 business days.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eUnited States (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEFTA Countries (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eWorldwide: 7–14 business days, selected locations.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"NorrChemica™","offers":[{"title":"1.0 g","offer_id":53501598007633,"sku":"NOR-4233334-1g","price":29.0,"currency_code":"EUR","in_stock":true},{"title":"2.0 g","offer_id":53501598040401,"sku":"NOR-4233334-2g","price":48.0,"currency_code":"EUR","in_stock":true},{"title":"5.0 g","offer_id":53501598073169,"sku":"NOR-4233334-5g","price":99.0,"currency_code":"EUR","in_stock":true},{"title":"10 g","offer_id":53501598105937,"sku":"NOR-4233334-10g","price":152.0,"currency_code":"EUR","in_stock":true},{"title":"25 g","offer_id":53501598138705,"sku":"NOR-4233334-25g","price":336.0,"currency_code":"EUR","in_stock":true},{"title":"50 g","offer_id":53501598171473,"sku":"NOR-4233334-50g","price":650.0,"currency_code":"EUR","in_stock":true},{"title":"100 g","offer_id":53501598204241,"sku":"NOR-4233334-100g","price":1254.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/6357\/1793\/files\/PTAD_NORRCHEMICAMULTILISTING_95__VR.png?v=1775917944"},{"product_id":"edc-hcl-edci-hcl-25952-53-8-99","title":"EDC·HCl (EDCI·HCl) | CAS 25952-53-8 | ≥99%","description":"\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eTechnical Specifications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; font-size: 0.95em; border: 1px solid #e4e8f0; border-top: none; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eCAS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e25952-53-8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eEC \/ EINECS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e247-361-2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMDL Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eMFCD00012503\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eRTECS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eFF2200000\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSMILES\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eCCN=C=NCCCN(C)C.Cl\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChI\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eInChI=1S\/C8H17N3.ClH\/c1-4-9-8-10-6-5-7-11(2)3;\/h4-7H2,1-3H3;1H\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChIKey\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eFPQQSJJWHUJYPU-UHFFFAOYSA-N\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePubChem CID\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e2723939\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Formula\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eC₈H₁₈ClN₃\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Weight\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e191.7 g\/mol\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMelting Point\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e110-115 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSolubility\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eSoluble in water, soluble in polar organic solvents\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eLog P\u003csub\u003eow\u003c\/sub\u003e\n\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e-2.98\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePurity\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e≥99%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePhysical Form\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eWhite solid\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eHS Code\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e2925.29\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eShelf Life\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eRetest period: 24 months from date of manufacture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eStorage Conditions\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eStore refrigerated (2–8 °C) in a tightly sealed container, protected from moisture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eProduct Description \u0026amp; Scientific Applications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"padding: 16px 20px; border: 1px solid #e4e8f0; border-top: none; font-family: Georgia, 'Times New Roman', serif; font-size: 0.95em; line-height: 1.65; color: #333;\"\u003e\n\u003cp\u003e\u003cstrong\u003eEDC·HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride; EDAC; EDCI; WSC)\u003c\/strong\u003e is a standard water-soluble carbodiimide for zero-length crosslinking, amide-bond formation and bioconjugation chemistry. It activates a carboxylic acid to a reactive O-acylisourea, which a primary amine then attacks to form an amide bond, joining the two groups with no added spacer atoms. The O-acylisourea is short-lived in water: it can hydrolyse back to the acid, rearrange to an unreactive N-acylurea, or, in peptide coupling of α-chiral amino-acid derivatives, contribute to oxazolone-mediated racemisation. Adding NHS or sulfo-NHS diverts it to a more persistent amine-reactive ester and improves aqueous carboxyl-to-amine coupling; HOBt or HOAt is used in peptide synthesis to reduce racemisation. EDC's practical advantage over DCC is that its urea by-product is water-soluble and removable by aqueous extraction or washing. Activation is commonly run in MES or another non-amine, non-carboxylate buffer near pH 5–6, then shifted nearer neutral for amine coupling. EDC also activates 5′-phosphate groups. EDC·HCl is supplied as a white crystalline powder, soluble in water; keep cold and dry.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCarbodiimide activation and amide-bond formation\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eAs a zero-length crosslinker, EDC forms a direct amide bond between a carboxyl and a primary amine, adding no spacer atoms.\u003c\/li\u003e\n\u003cli\u003eEDC activates the carboxyl to an O-acylisourea, which a primary amine displaces to give the amide; because the intermediate is unstable in water, hydrolysis competes with coupling.\u003c\/li\u003e\n\u003cli\u003eAdding NHS or sulfo-NHS converts the O-acylisourea to a more persistent amine-reactive ester, limiting hydrolysis and N-acylurea formation and improving productive amide formation.\u003c\/li\u003e\n\u003cli\u003eThe urea by-product is water-soluble and removed by aqueous extraction or washing — the main handling advantage over DCC, whose urea is poorly soluble.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003ePeptide and solution-phase synthesis\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEDC·HCl is a standard water-compatible carbodiimide for solution-phase amide and peptide coupling, with the soluble urea by-product simplifying work-up.\u003c\/li\u003e\n\u003cli\u003eRun with HOBt or HOAt, EDC gives peptide couplings with reduced racemisation by converting the O-acylisourea into a less epimerisation-prone active ester.\u003c\/li\u003e\n\u003cli\u003eWith catalytic DMAP, EDC is also used in Steglich-type esterification and acylation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eBioconjugation and biomolecule modification\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEDC, alone or with NHS or sulfo-NHS, couples carboxyls to primary amines in aqueous workflows, with activation usually run mildly acidic and amine coupling shifted nearer neutral.\u003c\/li\u003e\n\u003cli\u003eIt is a standard reagent for hapten–carrier conjugation, covalently attaching small haptens to carrier proteins such as KLH or BSA to prepare immunogens.\u003c\/li\u003e\n\u003cli\u003eWith imidazole, EDC activates 5′-phosphate groups of DNA and RNA oligonucleotides, enabling oligonucleotide labelling, immobilisation or amine conjugation through phosphoramidate bond formation.\u003c\/li\u003e\n\u003cli\u003eMES or another non-amine, non-carboxylate buffer near pH 5–6 is preferred for activation; Tris, glycine and carboxylate-containing buffers or additives are avoided during the activation step.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eSurface functionalisation, biosensors and biomaterials\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEDC with NHS or sulfo-NHS is the standard amine-coupling chemistry for immobilising ligands on carboxylated biosensor surfaces, including carboxymethyl-dextran SPR chips and 11-mercaptoundecanoic-acid self-assembled monolayers.\u003c\/li\u003e\n\u003cli\u003eThe same activation conjugates biomolecules to carboxylated microspheres, nanoparticles and microarray supports through stable amide bonds.\u003c\/li\u003e\n\u003cli\u003eIn biomaterials, EDC\/NHS is widely used for zero-length crosslinking of collagen and gelatin scaffolds, where the amide crosslinks commonly raise collagen denaturation or shrinkage temperature, reduce swelling and increase resistance to enzymatic degradation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFurther Reading\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor guidance on selecting between carbodiimides, aminium\/uronium salts, phosphonium salts and other reagent classes for amide and peptide bond formation, see NorrChemica's Lab Journal guide: \u003ca href=\"https:\/\/www.norrchemica.com\/blogs\/lab-journal\/choosing-a-coupling-reagent-for-amide-and-peptide-bond-formation\"\u003eChoosing a Coupling Reagent for Amide and Peptide Bond Formation\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eShipping Destinations\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e4e8f0; border-top: none; padding: 12px 16px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.95em;\"\u003e\u003cul style=\"margin: 0; padding: 0; list-style: none;\"\u003e\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEU, UK \u0026amp; Switzerland only: 2–7 business days\u003c\/li\u003e\u003c\/ul\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"NorrChemica™","offers":[{"title":"10 g","offer_id":53913505661265,"sku":"NOR-25952538-10g","price":24.2,"currency_code":"EUR","in_stock":true},{"title":"25 g","offer_id":53913505694033,"sku":"NOR-25952538-25g","price":39.2,"currency_code":"EUR","in_stock":true},{"title":"50 g","offer_id":53913505726801,"sku":"NOR-25952538-50g","price":69.2,"currency_code":"EUR","in_stock":true},{"title":"100 g","offer_id":53913505759569,"sku":"NOR-25952538-100g","price":98.2,"currency_code":"EUR","in_stock":true},{"title":"250 g","offer_id":53913505792337,"sku":"NOR-25952538-250g","price":149.2,"currency_code":"EUR","in_stock":true},{"title":"500 g","offer_id":53957445910865,"sku":"NOR-25952538-500g","price":229.2,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/6357\/1793\/files\/EDC_HCl_ffa80336-8d1c-44e4-9b30-a394efe706b1.png?v=1780423229"},{"product_id":"sulfo-nhs-sodium-salt-cas-106627-54-7","title":"Sulfo-NHS sodium salt | CAS 106627-54-7 | ≥97%","description":"\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eTechnical Specifications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; font-size: 0.95em; border: 1px solid #e4e8f0; border-top: none; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eCAS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e106627-54-7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eEC \/ EINECS Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e680-151-2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMDL Number\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eMFCD00043100\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eSMILES\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eC1C(C(=O)N(C1=O)O)S(=O)(=O)[O-].[Na+]\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChI\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eInChI=1S\/C4H5NO6S.Na\/c6-3-1-2(12(9,10)11)4(7)5(3)8;\/h2,8H,1H2,(H,9,10,11);\/q;+1\/p-1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eInChIKey\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0; word-break: break-all;\"\u003eRPENMORRBUTCPR-UHFFFAOYSA-M\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePubChem CID\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e3520574\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Formula\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eC₄H₄NNaO₆S\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMolecular Weight\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e217.13 g\/mol\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eMelting Point\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e250 °C (dec.)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePurity\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e≥97%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003ePhysical Form\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eWhite to off-white powder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eHS Code\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003e2928.00\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eShelf Life\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eRetest period: 36 months from date of manufacture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 9px 16px; font-weight: 600; color: #002147; width: 200px; border-bottom: 1px solid #e4e8f0; background: #f7f8fb; font-size: 0.95em; vertical-align: top;\"\u003eStorage Conditions\u003c\/td\u003e\n\u003ctd style=\"padding: 9px 16px; color: #333; border-bottom: 1px solid #e4e8f0;\"\u003eStore refrigerated (2–8 °C) in a tightly sealed container, protected from moisture.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eProduct Description \u0026amp; Scientific Applications\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"padding: 16px 20px; border: 1px solid #e4e8f0; border-top: none; font-family: Georgia, 'Times New Roman', serif; font-size: 0.95em; line-height: 1.65; color: #333;\"\u003e\n\u003cp\u003e\u003cstrong\u003eSulfo-NHS (N-hydroxysulfosuccinimide sodium salt; sodium 1-hydroxy-2,5-dioxopyrrolidine-3-sulfonate)\u003c\/strong\u003e is the water-soluble, sulfonated analogue of NHS and a standard additive for carbodiimide-mediated amide-bond formation and bioconjugation. Paired with a carbodiimide such as EDC, it converts a carboxylic acid into a water-soluble, amine-reactive sulfo-NHS ester: EDC first forms a short-lived O-acylisourea, which sulfo-NHS intercepts before hydrolysis or rearrangement to the unreactive N-acylurea. The resulting sulfo-NHS ester is more persistent than the O-acylisourea intermediate and remains reactive toward primary amines, improving productive EDC-mediated coupling. Two properties distinguish it from NHS: the charged sulfonate makes sulfo-NHS and its active esters directly water-soluble, allowing many labelling and coupling workflows to run in aqueous buffer without the organic cosolvent often needed for non-sulfonated NHS-ester reagents; and that same charge makes sulfo-NHS esters membrane-impermeant, restricting modification to cell-surface or otherwise solvent-exposed amines. Sulfo-NHS is supplied as a crystalline solid, soluble in water, and should be stored cold and dry.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCarbodiimide-mediated carboxyl-to-amine conjugation\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWith EDC, sulfo-NHS traps the O-acylisourea before hydrolysis or N-acylurea formation, diverting the activated acid into a more persistent, water-soluble sulfo-NHS ester and improving productive amide formation.\u003c\/li\u003e\n\u003cli\u003eThe sulfo-NHS ester acylates primary amines — lysine ε-amines and N-terminal α-amines — under mild conditions, giving stable amide bonds; EDC\/sulfo-NHS is a standard zero-length carboxyl-to-amine conjugation system.\u003c\/li\u003e\n\u003cli\u003eCarboxyl activation is typically run near pH 5–6 and amine coupling near neutral to mildly alkaline pH; because the ester is more persistent and water-soluble, activation and amine-coupling can be separated into a two-step procedure in fully aqueous media.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eProtein labelling and cell-surface modification\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eAmine-reactive sulfo-NHS-ester reagents — sulfo-NHS-biotin and its longer-spacer and cleavable-disulfide variants — acylate solvent-accessible lysine ε-amines and N-termini of antibodies and proteins, core chemistry for antibody biotinylation and protein labelling.\u003c\/li\u003e\n\u003cli\u003eBecause the charged sulfonate prevents sulfo-NHS ester reagents from crossing the plasma membrane, they label only the exterior proteins of intact cells, enabling selective cell-surface biotinylation and surface-proteome capture; cleavable disulfide-spacer variants release captured proteins on reduction.\u003c\/li\u003e\n\u003cli\u003eWater solubility allows labelling in aqueous buffer without organic cosolvent, suited to cells and proteins that do not tolerate DMSO or DMF.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eSurface functionalisation and biosensors\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEDC\/NHS or EDC\/sulfo-NHS activation of carboxylated surfaces — carboxymethyl-dextran sensor coatings and carboxyl-terminated self-assembled monolayers — covalently immobilises protein ligands on SPR and related optical biosensors.\u003c\/li\u003e\n\u003cli\u003eThe same chemistry functionalises carboxylated nanoparticles, microspheres and microarray slides through stable amide linkages; residual activated surface esters are capped with ethanolamine after ligand immobilisation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCrosslinking and structural biology\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe water-soluble homobifunctional crosslinker BS3 (sulfo-DSS) bridges proximal lysine ε-amines across an 11.4 Å spacer; being charged and membrane-impermeant, it is confined to the surface of intact cells, complementing membrane-permeant DSS for mapping inside-versus-outside topology.\u003c\/li\u003e\n\u003cli\u003eHeterobifunctional sulfo-SMCC carries a sulfo-NHS ester at one end and a maleimide at the other, joining a protein amine to a second molecule's thiol in a controlled, two-step amine-to-thiol sequence that limits self-conjugation — used for antibody–enzyme and immunogen–carrier conjugates.\u003c\/li\u003e\n\u003cli\u003eEDC\/sulfo-NHS forms zero-length amide crosslinks between protein carboxylates and lysine amines for protein–protein interaction studies; water-soluble NHS-ester crosslinkers such as BS3 are used in lysine-directed crosslinking mass spectrometry (XL-MS).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eFurther Reading\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor guidance on selecting between carbodiimides, aminium\/uronium salts, phosphonium salts and other reagent classes for amide and peptide bond formation, see NorrChemica's Lab Journal guide: \u003ca href=\"https:\/\/www.norrchemica.com\/blogs\/lab-journal\/choosing-a-coupling-reagent-for-amide-and-peptide-bond-formation\"\u003eChoosing a Coupling Reagent for Amide and Peptide Bond Formation\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv style=\"margin-bottom: 28px;\"\u003e\n\u003cdiv style=\"background: #002147; padding: 10px 20px; margin-bottom: 0;\"\u003e  \u003ch3 style=\"margin: 0; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.70em; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; color: #fff;\"\u003eShipping Destinations\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e4e8f0; border-top: none; padding: 12px 16px; font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; font-size: 0.95em;\"\u003e\u003cul style=\"margin: 0; padding: 0; list-style: none;\"\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEU \u0026amp; UK: Priority delivery, 2–5 business days.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eUnited States (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eEFTA Countries (DDP): 3–7 business days, duties and taxes prepaid.\u003c\/li\u003e\n\u003cli style=\"padding: 5px 0; border-bottom: 1px solid #f0f0f0;\"\u003e\n\u003cspan style=\"display: inline-block; width: 7px; height: 7px; background: #002147; border-radius: 50%; margin-right: 10px; vertical-align: middle;\"\u003e\u003c\/span\u003eWorldwide: 7–14 business days, selected locations.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"NorrChemica™","offers":[{"title":"500 mg","offer_id":53970974245201,"sku":"NOR-106627547-500mg","price":34.2,"currency_code":"EUR","in_stock":true},{"title":"1.0 g","offer_id":53970974277969,"sku":"NOR-106627547-1g","price":54.2,"currency_code":"EUR","in_stock":true},{"title":"2.0 g","offer_id":53970974310737,"sku":"NOR-106627547-2g","price":89.2,"currency_code":"EUR","in_stock":true},{"title":"5.0 g","offer_id":53970974343505,"sku":"NOR-106627547-5g","price":169.0,"currency_code":"EUR","in_stock":true},{"title":"10 g","offer_id":53970974376273,"sku":"NOR-106627547-10g","price":293.0,"currency_code":"EUR","in_stock":true},{"title":"25 g","offer_id":53970974409041,"sku":"NOR-106627547-25g","price":579.0,"currency_code":"EUR","in_stock":true},{"title":"50 g","offer_id":53970974441809,"sku":"NOR-106627547-50g","price":1145.0,"currency_code":"EUR","in_stock":true},{"title":"100 g","offer_id":53970974474577,"sku":"NOR-106627547-100g","price":2250.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/6357\/1793\/files\/sulfonhs_card_ns.png?v=1780567877"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0954\/6357\/1793\/collections\/norrchemica_click_bioorthogonal_1080.png?v=1781876340","url":"https:\/\/www.norrchemica.com\/collections\/bioconjugation-click-chemistry.oembed","provider":"NorrChemica","version":"1.0","type":"link"}