A sustainable and green MSPE-HPLC-DAD method for trace analysis of apremilast using new TMMS/decanoic acid-modified...

This study presents a novel, selective, and rapid magnetic solid-phase extraction (MSPE) method coupled with HPLC-DAD for the trace-level determination of apremilast (APM). To achieve high extraction efficiency and minimize matrix interferences, Fe₃O₄ magnetic nanoparticles were functionalized using a synchronized trimethoxymethylsilane (TMMS) and decanoic acid modification strategy for the first time. The synthesized Fe₃O₄@TMMS/decanoic acid sorbent was comprehensively characterized via XRD, FT-IR, SEM, and EDX to confirm successful surface functionalization and morphological stability. Key extraction parameters, including sample pH, desorption solvent type and volume, and adsorption/desorption times, were systematically optimized. Under optimal conditions (pH 5.0, isopropyl alcohol as desorption solvent), the method exhibited a robust linear range of 125.0-1000.0 ng mL^-1 for APM. The practical reliability of the developed protocol was validated with triplicate analyses of 100 ng per mL APM solutions, yielding relative standard deviations (RSD) below 5.1% and excellent recovery values between 95.3% and 103.2%. The results demonstrate that this functionalized magnetic sorbent offers a high-capacity, cost-effective, and highly reproducible alternative for the routine monitoring of apremilast in complex matrices. The overall method performance and eco-friendliness were quantitatively validated using AMRI (70), AGREE (0.70), AGREEprep (0.63), and SAMI (26) metrics, establishing the procedure as a reliable and sustainable analytical tool.