{"product_id":"c-peptide-3-33-human","title":"C-Peptide (3-33), Human","description":"\u003cdiv style=\"max-width:1400px; margin:0 auto; padding:40px 20px; font-family:'Open Sans',sans-serif; font-weight:300; background:#fff; color:#333; font-size:0.95rem; box-sizing:border-box;\"\u003e\n  \u003cdiv style=\"display:flex; flex-direction:column; gap:20px;\"\u003e\n\u003ch2 style=\"margin:0; font-weight:600;\"\u003eC-Peptide (3-33), Human – Catalog #B2026671\u003c\/h2\u003e\n\u003cp\u003eC-Peptide (3-33), Human (Catalog #B2026671) is a fragment of human proinsulin-derived C-peptide supplied as 0.5 mg of lyophilized powder. The C-peptide is the connecting chain linking the A and B chains of insulin. During insulin synthesis and secretion, proinsulin is proteolytically cleaved to release equimolar amounts of insulin and C-peptide. Because C-peptide is not extracted by the liver on first pass (unlike insulin), plasma C-peptide levels directly reflect pancreatic beta-cell insulin secretion.\u003c\/p\u003e\n\u003cdiv style=\"overflow-x:auto; max-width:100%; margin-bottom:20px;\"\u003e\n\u003ctable style=\"width:100%; max-width:640px; border-collapse:collapse;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eCatalog number:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eB2026671\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eLot number:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eBatch dependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eExpiration Date:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eBatch dependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eAmount:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e0.5 mg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eMolecular Weight or Concentration:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eN\/A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eSupplied as:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eLyophilized Powder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eSource:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eHuman (synthetic)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eDiabetes research, assessment of beta-cell function, glucose homeostasis studies, insulin secretion measurement, metabolic research\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eStorage:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e−20°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eKeywords:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eC-peptide, C-peptide (3-33), Human C-peptide, Proinsulin C-peptide, Insulin C-peptide, Connecting peptide, Beta-cell marker, Insulin secretion marker\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eGrade:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eBiotechnology grade. All products are highly pure. All solutions are made with Type I ultrapure water (resistivity \u0026gt;18 MΩ-cm) and are filtered through 0.22 um.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eScientific Overview\u003c\/h3\u003e\n\u003cp\u003eC-peptide is a 31-amino-acid peptide that links the A and B chains of insulin within the proinsulin molecule. Proinsulin undergoes proteolytic cleavage by endopeptidases to release mature insulin and C-peptide in a 1:1 molar ratio. Unlike insulin, C-peptide is not extracted by the liver during first-pass circulation, making its plasma concentration a faithful biomarker of pancreatic beta-cell secretion rate and function.\u003c\/p\u003e\n\u003cp\u003eThe C-peptide (3-33) fragment represents the physiologically active form used in many research applications. C-peptide itself has been shown to have biological effects independent of insulin, including roles in vasodilation, cellular signaling, and metabolic regulation.\u003c\/p\u003e\n\u003cp\u003eKey applications include:\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eDirect measurement of endogenous insulin secretion in diabetes diagnosis and classification\u003c\/li\u003e\n\u003cli\u003eAssessment of pancreatic beta-cell function and reserve\u003c\/li\u003e\n\u003cli\u003eValidation of metabolic assays and glucose homeostasis studies\u003c\/li\u003e\n\u003cli\u003eResearch into C-peptide's independent biological effects on vascular and cellular function\u003c\/li\u003e\n\u003cli\u003eUse as a reference standard in immunoassays and bioanalytical methods\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eUsage \u0026amp; Handling Guidance\u003c\/h3\u003e\n\u003cp\u003eStore lyophilized powder at −20°C. Reconstitute in sterile, distilled water or phosphate-buffered saline (PBS) immediately before use. Prepare aliquots to minimize repeated freeze–thaw cycles, which can affect peptide integrity.\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eReconstitution:\u003c\/strong\u003e Dissolve in appropriate assay buffer; reconstitution concentration is assay-dependent. Request the COA\/TDS for lot-specific information.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStability:\u003c\/strong\u003e In solution, C-peptide may aggregate or degrade over time. Use freshly prepared solutions when possible, or store at 2–8°C for short-term use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePurity and identity:\u003c\/strong\u003e Request available lot documentation (COA, HPLC trace) to confirm sequence and purity.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eWhat You Get\u003c\/h3\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e0.5 mg of human C-peptide (3-33), supplied as lyophilized powder\u003c\/li\u003e\n\u003cli\u003eHigh-purity peptide fragment for research and assay development\u003c\/li\u003e\n\u003cli\u003eA stable marker of endogenous insulin secretion\u003c\/li\u003e\n\u003cli\u003eFor research use only (RUO)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eWhy Researchers Choose It\u003c\/h3\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eDirect reflection of pancreatic beta-cell insulin secretion (not hepatically extracted)\u003c\/li\u003e\n\u003cli\u003eWell-established biomarker in diabetes and metabolic research\u003c\/li\u003e\n\u003cli\u003eStable during circulation, enabling accurate in vivo measurement\u003c\/li\u003e\n\u003cli\u003eConvenient lyophilized format for long-term storage\u003c\/li\u003e\n\u003cli\u003eEssential for distinguishing type 1 from type 2 diabetes and assessing beta-cell reserve\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eFrequently Asked Questions (FAQ)\u003c\/h3\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat is C-peptide and why is it important?\u003c\/strong\u003e\u003cbr\u003eC-peptide is the connecting chain cleaved from proinsulin when insulin is synthesized. Unlike insulin, it is not removed by the liver, so its plasma level directly reflects the rate of insulin secretion by beta cells.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow does C-peptide (3-33) differ from full-length C-peptide?\u003c\/strong\u003e\u003cbr\u003eC-peptide (3-33) is the physiologically active form after proteolytic processing. It is the form measured clinically to assess endogenous insulin production.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow should I reconstitute the peptide?\u003c\/strong\u003e\u003cbr\u003eDissolve in sterile distilled water or PBS. The specific concentration depends on your assay. Request the COA\/TDS for lot-specific guidance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan this peptide be used in immunoassays?\u003c\/strong\u003e\u003cbr\u003eYes. C-peptide is widely used as a reference standard in radioimmunoassay (RIA) and immunometric assays for measuring circulating C-peptide levels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow long is the lyophilized powder stable?\u003c\/strong\u003e\u003cbr\u003eAt −20°C, lyophilized peptides are generally stable for years. Request available lot-specific stability data from the supplier.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIs lot-specific documentation available?\u003c\/strong\u003e\u003cbr\u003eYes. Request a quote or contact us for available COA, HPLC, and other analytical data for your lot.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv style=\"margin-top:20px; font-weight:bold; color:#c8102e;\"\u003eThis product is for Research Use Only (RUO). It is not intended for diagnostic or therapeutic use in humans or animals.\u003c\/div\u003e\n\u003chr\u003e\n\u003ch4\u003eReferences\u003c\/h4\u003e\n\u003cul style=\"padding-left:0; margin:0; list-style:none;\"\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003eFaber OK, Binder C. C-peptide: an index of insulin secretion. \u003cem\u003eDiabetes Metab Rev.\u003c\/em\u003e 1986;2(3-4):331-45.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1002\/dmr.5610020307\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003ePolonsky KS, Rubenstein AH. C-peptide as a measure of the secretion and hepatic extraction of insulin. Pitfalls and limitations. \u003cem\u003eDiabetes.\u003c\/em\u003e 1984;33(5):486-94.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.2337\/diab.33.5.486\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003eJones AG, Hattersley AT. The clinical utility of C-peptide measurement in the care of patients with diabetes. \u003cem\u003eDiabet Med.\u003c\/em\u003e 2013;30(7):803-17.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1111\/dme.12159\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003eFu Z, Gilbert ER, Liu D. Regulation of insulin synthesis and secretion and pancreatic Beta-cell dysfunction in diabetes. \u003cem\u003eCurr Diabetes Rev.\u003c\/em\u003e 2013;9(1):25-53.\u003c\/span\u003e\u003ca href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/22974359\/\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e","brand":"Molecular Depot","offers":[{"title":"Default Title","offer_id":52809017360682,"sku":"BTS-B2026671","price":585.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/B2026671.png?v=1790859405","url":"https:\/\/bluetigerscientific.com\/products\/c-peptide-3-33-human","provider":"Blue Tiger Scientific","version":"1.0","type":"link"}