Task Specific Adsorbent Based on Porous Monolith for Efficient Capture of Synthetic Colorants in Beverages and Preserved Fruits Prior to Chromatographic Analysis

Abstract

Efficient capture is an indispensable step in the highly sensitive quantification of synthetic colorants (SCs) in food industry. In this scenario, a new task specific adsorbent based on porous monolith (TSA) was conveniently fabricated and utilized as the adsorptive medium of multiple monolithic fibers solid phase microextraction (MF-SPME) for entrapment of SCs in beverages and preserved fruit samples. Various techniques were employed to characterize the prepared TSA and evidenced there were abundant functional groups, pores and satisfactory surface area. The introduced TSA/MF-SPME presented good entrapment performance towards SCs including sunset yellow, allura red and para red through multiple interactions. The enrichment factors were in ranges of 88-106 and 71-101 for beverage and preserved fruit, respectively. Under the optimized fabrication conditions of TSA and extraction parameters, sensitive and reliable method for the quantification of studied SCs in beverage and preserved fruit samples was developed by the combination of TSA/MF-SPME with HPLC/DAD. Limits of detection were 0.015-0.018 μg/L for beverage and 0.057-0.069 μg/kg for preserved fruit samples. The established approach also possessed some features such as wide linear ranges, good precision, low consumptions of sample and organic solvent. The applicability of suggestion method was verified by the quantification of investigated analytes in various beverage and preserved fruit samples, and good recoveries with different fortified concentrations were achieved.

Keywords: Solid phase microextraction, monolith, adsorbent, synthetic colorants, food