An optimized protocol to assess trypsin activity in biological samples

• Published in: Monatshefte für Chemie 2023-02, Vol.154 (2), p.267-277
• Main Authors: Hadwan, Mahmoud Hussein, Al-Obaidy, Saba S. M., Al-Kawaz, Hawraa Saad, Almashhedy, Lamia A., Kadhum, Mohammed A., Khudhair, Dunia Abbas, Hadwan, Asad M., Hadwan, Muntadher M.
• Format: Article
• Language: English
• Subjects: Acidification; Analytical Chemistry; Biological activity; Biological properties; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Cytochromes; Enzymes; Hydrogen peroxide; Inorganic Chemistry; Intestine; Organic Chemistry; Original Paper; Oxidation; Peroxidase; Pharmaceuticals; Physical Chemistry; Reliability analysis; Response surface methodology; Spectrophotometry; Sulfuric acid; Synthesis; Theoretical and Computational Chemistry; Thiamine; Trypsin
• ISSN: 0026-9247; 1434-4475
• DOI: 10.1007/s00706-022-03028-1

Trypsin is an enzyme that facilitates digestion. It is found in the small intestine and may also be synthesized by bacteria, plants, and fungi. However, it is mainly synthesized for commercial use from cattle pancreases. Serum trypsin determination seems to be a specific diagnostic for acute pancreatitis. Therefore, the development of improved trypsin activity protocols is essential for clinical pathology and pharmaceutical research. In this study, a simple spectrophotometric procedure for trypsin, a pancreatic protease, was developed. The current protocol utilized a previously known peroxidase-like reaction to estimate the trypsin activity. An additional acidification step is employed to improve the efficiency of the protocol. Trypsin has the ability to preferentially cleave the natural compound cytochrome c into heme-peptide fragments. In our study, the resulting peroxidase-like activity was catalyzed by the oxidation of 3,3ʹ,5,5ʹ-tetramethylbenzidine in the presence of H 2 O 2 . Sulfuric acid was added to stop the enzymatic reaction before recording the absorbance at 450 nm. To optimize the formation of the end product, we used the response surface methodology to apply the Box–Behnken design to assess the assay's precision. The reliability of this new method was compared to a Bland–Altman plot analysis of trypsin activity in matched samples using the standard procedure. The protocol allowed for trypsin investigations in the 5–1500 ng/cm 3 range, with a detection limit of 0.691 ng/cm 3 . The protocol demonstrated higher accuracy in the measurement of 500 ng/cm 3 trypsin solution, with a relative standard percentage error of 1.4–2.2%. This new protocol was verified against a Bland–Altman plot analysis of trypsin activity in matched samples using the Thiamine–Trypsin test, confirming its potential for application in pharmaceutical development and disease treatment. Our study demonstrated a simple, rapid, low-cost, sensitive, and selective method for assessment of the trypsin enzyme, which can be used to study the clinical importance and pharmaceutical significance of the trypsin enzyme. Graphical abstract