An intelligent cellulose-based sorbent (Cell-Azo) was developed by grafting azobenzene onto cellulose via atom-transfer radical polymerization, enabling the light-driven solid-phase extraction of amphetamine (AMP). Successful grafting was verified by FT-IR and XPS, with UV-vis spectroscopy demonstrating the rapid and reversible trans-cis isomerization upon alternating UV/visible light irradiation. Batch adsorption studies revealed a maximum capacity of 19.86 mg·g-1 at pH 9.0, governed by synergistic electrostatic, π-π stacking, and hydrogen-bonding interactions. The core functionality of the switch was demonstrated by triggering AMP release with UV light, achieving a high desorption efficiency of 90.54%, significantly surpassing the -1), low LOD (7 μg·L-1) and LOQ (23.33 μg·L-1), and satisfactory precision (RSD < 5.1%). When applied to spiked urine samples, the method achieved recoveries of 69.53-75.68%, demonstrating the potential application of Cell-Azo as an efficient, green, and controllable alternative for trace AMP analysis in complex matrices.
Xie et al. (Fri,) studied this question.