Credible and Facile Fluorometric Detection of Soybean Trypsin Inhibitor Activity with a Water-Soluble Poly(diphenylacetylene) Derivative

Abstract

Herein, a novel method for fluorometric detection of soybean trypsin inhibitor (SBTI) activity based on a water-soluble poly(diphenylacetylene) derivative was reported. Fluorescence quenching of the polymer via p-nitroaniline, produced from the trypsin-catalyzed decomposition of N-benzoyl-DL-arginine-4-nitroanilide hydrochloride (L-BAPA), was well described using the Stern–Volmer equation. SBTI activity was quantitatively assessed based on changes in the fluorescence intensity of the polymer. This strategy has several advantages, such as high sensitivity and ease of operation. Moreover, its applicability to other biochemical analyses is promising.

Keywords

Fluorometric detection / Soybean trypsin inhibitor / Inhibition activity / Fluorescence quenching

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