Chia seed mucilage biosorbent synergism with hydrophobic iron (III)-natural phenolic nanoparticles for dispersive solid-phase extraction of tetracycline residues in milk and honey samples before HPLC analysis.

This study utilized the synergistic effectiveness of chia seed mucilage and iron (III)-natural phenolic nanoparticles as biosorbents for the first time in the dispersive solid-phase extraction (DSPE) of oxytetracycline, tetracycline, chlortetracycline, and doxycycline followed by HPLC-UV quantification. An in-situ iron (III)-natural phenolic solid adsorbent was created using natural phenolics found in the copper pod tree bark. An ultrasonic-assisted extraction was performed to enhance the extraction efficiency of DSPE-based biosorbents. Excellent linearity with R2 greater than 0.9957 was achieved, with detection limits between 0.7 and 2.0 μg L-1 for milk, 2.5 and 7.5 μg kg-1 for honey, and precisions below 9.1 %. The DSPE-based biosorbent was effectively applied to quantify tetracycline residues in milk and honey samples, yielding recoveries from 72.1 to 116.2 %. This method showed potential as an alternative simple, low-cost, eco-friendly, biodegradable, and reusable biosorbent to determine tetracycline residues in food.