Synthesis and characterization of a molecularly imprinted silica gel sorbent for the on-line determination of trace sudan I in chilli powder through high-performance liquid chromatography

TLDR: The results showed that the imprinted sorbent exhibited good recognition and selective ability, offered a faster kinetics for the adsorption and desorption of Sudan I than the non-imprinted sorbent, and had a saturated binding capacity (Qmax) that reached 33.47 mg g-1.

Abstract: A highly selective imprinted polymer was synthesized by a surface molecular imprinting technique in combination with a sol−gel process. The imprinted polymer was evaluated by FT-IR and static and kinetic adsorption experiments. The results showed that the imprinted sorbent exhibited good recognition and selective ability, offered a faster kinetics for the adsorption and desorption of Sudan I than the non-imprinted sorbent, a saturated binding capacity (Qmax) that reached 33.47 mg g-1. The prepared sorbent was applied for the determination of trace Sudan I through on-line solid-phase coupled with high-performance liquid chromatography (SPE-HPLC). With a loading flow rate of 1.5 mL min-1 for sampling 50 mL, an enrichment factor of 1266 was achieved. The detection limit (S/N = 3) was 1.2 ng L-1, and the peak area precision (RSD) for five replicate detections of 0.01 μg L-1 Sudan I was 3.66%. The Sudan I in the chilli powder from the local market was determined at three levels (0.25, 0.5, and 1.0 ng g-1) with...