Supercritical fluid extraction of papaverine and noscapine from poppy capsules followed by preconcentration with magnetic nano Fe3O4@Cu@diphenylthiocarbazone particles
A novel magnetite adsorbent modified with copper and diphenylthiocarbazone was synthesized and used as a sorbent for magnetic solid phase extraction (MSPE) of two opium alkaloids: papaverine and noscapine. Supercritical fluid extraction (SFE) was used to extract the analytes from poppy capsules. The extracts were preconcentrated by magnetic solid phase extraction. Separation and determination of both opium alkaloids were performed using high performance liquid chromatography with an ultra-violet detector. The SFE parameters were optimized through a Taguchi orthogonal array experimental design. Under the optimal conditions, broad linear dynamic ranges of 0.3–180 μg L−1 (0.9981 < R2 < 0.9993) and 0.3–4 mg kg−1 (0.9921 < R2 < 0.9971), favorable limits of detection of 1 μg L−1 and 0.1 mg kg−1, and suitable precisions with RSDs% in the range of 4.3–5.5% and 5.8–7.7% were obtained for MSPE and SFE-MSPE, respectively. The capability of the method was tested by analyzing different real samples including urinary samples and poppy capsules.