Clove essential oil impregnated cellulose paper as a sustainable sorbent for rapid microextraction of sedative drugs in complex beverages matrices

Abstract

A novel disposable in-tip cellulose paper (DICP) device, functionalized with clove essential oil (CEO), was developed for the microextraction of five sedative and antihistaminic drugs viz. chlorpheniramine, pheniramine, ketamine, diazepam, and lorazepam; from beverages commonly encountered in drug-facilitated crimes (DFCs), including fruit juice, tea, milk, and water. The DICP device was fabricated by dip-coating cellulose paper (CP) with 2 % CEO (in hexane), cutting into rectangular strips, and inserting them into a 1000 μL micropipette tip. The extraction involved 30 aspiration–dispensing cycles for analyte adsorption, followed by 20 cycles for desorption using 0.5 mL ethanol. The method exhibited excellent linearity (0.1–5 μg mL⁻¹; R² > 0.994) with limits of quantification between 0.071 and 0.094 μg mL⁻¹, accuracy ranging from 85.9 % to 111.9 %, and intra- and inter-day precision below 8.7 % and 14.7 % RSD, respectively. Matrix effects remained below 13 % across all beverage types. The extraction mechanism is based on hydrophobic, hydrogen bonding, and π–π interactions between CEO and the analytes. The DICP platform supports high-throughput operation (12 samples/hour) and requires no auxiliary equipment. It is also highly cost-effective, as a single cellulose disc (150 mm diameter) yields approximately 30 extraction strips. Green analytical performance metrics; CACI (85), ComplexMoGAPI (85), and AGREE (0.64); underscore the method's sustainability, simplicity, and practicality. Applicability was further demonstrated through blind sample analysis at multiple concentration levels, simulating real forensic scenarios and confirming the method's reliability and operational feasibility for routine casework.