Secretin is a naturally occurring gastrointestinal peptide hormone and an important pharmaceutical diagnostic peptide. Pharmaceutical-grade synthetic human Secretin is a chemically synthesized 27-amino-acid peptide with an amino acid sequence identical to naturally occurring human secretin. It is generally supplied as an acetate salt and is used primarily as a diagnostic agent for evaluating pancreatic exocrine function and supporting the diagnosis of gastrinoma.
Synthetic human Secretin is identified by CAS Number 108153-74-8 and has a molecular weight of approximately 3039.44 Da. Unlike conventional small-molecule pharmaceutical APIs, Secretin is a peptide drug substance and therefore requires peptide-specific analytical characterization, including sequence identity, purity, related peptide analysis and biological activity evaluation. FDA regulatory documentation identifies synthetic human Secretin as a 27-amino-acid gastrointestinal peptide hormone.
Secretin consists of the sequence His-Ser-Asp-Gly-Thr-Phe-Thr-Ser-Glu-Leu-Ser-Arg-Leu-Arg-Glu-Gly-Ala-Arg-Leu-Gln-Arg-Leu-Leu-Gln-Gly-Leu-Val-NH₂. The C-terminal valine is amidated, which is an important structural characteristic of the biologically active peptide. The peptide is commonly represented by the molecular formula C130H220N44O39 with a molecular weight of 3039.44 Da. FDA labeling identifies the pharmaceutical substance as synthetic human Secretin acetate.
Secretin is manufactured through peptide synthesis rather than conventional fermentation of a protein. Its analytical characterization therefore focuses on peptide identity, chromatographic purity, related peptide impurities, residual process impurities and biological activity.
The primary pharmaceutical application of synthetic human Secretin is diagnostic. Secretin stimulates pancreatic ductal cells to release bicarbonate-rich pancreatic fluid, allowing pancreatic exocrine function to be evaluated. It can also stimulate gastrin secretion in patients with gastrinoma, making Secretin useful in diagnostic evaluation of suspected gastrinoma.
Synthetic human Secretin is also used during selected endoscopic procedures to facilitate identification of the ampulla of Vater and accessory papilla. Current U.S. labeling identifies human Secretin injection as a diagnostic product administered intravenously.
Secretin is a short peptide hormone consisting of 27 amino acids. It belongs to the secretin peptide family and acts through the secretin receptor. The peptide's biological function is closely associated with regulation of pancreatic bicarbonate secretion and gastrointestinal physiology.
Because peptide structure and biological activity are closely related, pharmaceutical-quality Secretin requires more than a simple chemical assay. Analytical programs may include HPLC or RP-HPLC purity, peptide mapping or sequence confirmation, mass spectrometry, related-peptide profiling and validated biological activity testing.
Secretin API quality control should emphasize peptide identity, chromatographic purity, molecular mass, related peptide impurities and biological potency. FDA documentation established a clinical-unit potency relationship in which 0.2 micrograms of synthetic human Secretin corresponds to 1 clinical unit. This corresponds to approximately 5,000 clinical units per milligram of peptide.
Conventional CMS fields such as melting point, residue on ignition and heavy metals are not appropriate universal release specifications for a synthetic peptide unless they are explicitly defined in a particular manufacturer's validated specification. The same principle applies to pH: the pH reported for a reconstituted finished injection should not be represented as the API's 1% solution pH.
Pharmaceutical-grade Secretin should be manufactured and controlled using peptide-specific processes and analytical procedures. Quality documentation can include Certificate of Analysis, peptide identity, molecular-weight confirmation, chromatographic purity, related-peptide profile, biological activity, residual-solvent testing and stability information as applicable to the manufacturing process.
Secretin is a peptide and should be protected from conditions that can promote degradation. Pharmaceutical finished products are commonly supplied as sterile lyophilized material. Storage and packaging requirements should be established according to the validated stability profile of the specific drug substance and formulation.
A technical package for Secretin API may include Certificate of Analysis, analytical methods, peptide purity data, identity and molecular-mass confirmation, potency information, impurity profile, residual-solvent information, stability data and applicable GMP or regulatory documentation.
Synthetic human Secretin is a well-characterized 27-amino-acid peptide with an established diagnostic pharmaceutical application. Its defined sequence, known molecular weight and established biological activity relationship make it suitable for controlled peptide manufacturing and pharmaceutical diagnostic applications.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| pH (1% Solution) | 3.0–6.5 |