Application of newly synthesized absorbent, polybutylene dodecanoate in dispersive solid-phase microextraction and spectrophotometric determination of quercetin in vegetables, fruits, and beverages.

Abstract

Quercetin is a naturally occurring and valuable bioactive compound found in various vegetables and fruits. The determination of quercetin concentrations in foodstuffs is of great importance; however, it is challenging due to matrix interference. A new sorbent, an aliphatic polyester, polybutylene dodecanedioate was synthesized for extraction of quercetin. It was characterized by NMR, FTIR, XPS, and DSC spectroscopy. A dispersive solid-phase microextraction method for spectrophotometric determination of quercetin in foodstuffs was developed using synthesized adsorbent. Under the optimized conditions, the proposed method showed a linear working range of 15-900 ng/mL, a limit of detection of 4.5 ng/mL, and an enrichment factor of 175 determined using matrix-compatible aqueous model solutions. Quercetin concentrations in vegetables, fruits, and beverages were determined to range from 1.20 to 42.0 mg per 100 g, with spike-test recovery values ranging from 91 to 99%. Determination of quercetin in the real samples was completed within only 10 min by the proposed methodology.