Yiwei Tang,He Meng,Wenxiu Wang,Yang Song,Shuo Wang,Zhuanying Li,Xianghong Wang,Xuelian Hu
An innovative core–shell magnetic molecularly imprinted polymers, Fe 3 O 4 @SiO 2 @MIPs, was elaborately tailored for specific separation and enrichment of olaquindox (OLA) and its metabolic marker methyl-3-quinoxaline-2carboxylic acid (MQCA). Herein, benefiting from the combination of functionalized magnetic nanoparticles (Fe 3 O 4 @SiO 2 ) and MIPs, Fe 3 O 4 @SiO 2 @MIPs not only possessed favorable magnetic properties and stability, avoiding tedious sample pretreatment process, but also demonstrated exceptional selective recognition ability and adsorption capacity, suppressing influence of coexisting interfering substances. Encouraged by prominent merits, Fe 3 O 4 @SiO 2 @MIPs-based magnetic solid phase extraction with HPLC method was developed, realizing simultaneous measurement of OLA and MQCA. Under optimal conditions, excellent linear ranges of 0–100 μg/L with detection limit of 0.175–0.271 μg/L were obtained. The proposed method was finally utilized for determination of OLA and MQCA in fish muscle and milk samples with satisfactory recoveries (80.56–95.26%) and relative standard deviation below 8.1%, furnishing a reliable and sensitive strategy for enrichment and detection residual veterinary drugs in food samples.
An electrochemical sensor based on a three-dimensional (3D) graphene/carbon nanotube (G/CNT) hybrid was developed for the sensitive detection of olaquindox (OLA). 3D G/CNT hybrid through covalent C-C bonding was fabricated by one-step synthesis using catalytic chemical vapor deposition. To construct the base of the sensor, a novel composite was fabricated by a functionalized 3D G/CNT with poly-(dimethy diallyl ammonium chloride) and Nafion via simple grind and ultrasonication dispersion methods. The electrochemical determination of OLA exhibited an oxidation peak at −0.685 V with a higher current response. Due to the effective surface area and active sites, a good linear relationship was observed between the OLA concentration and peak current over the range of 1.5 × 10−6–2.7 × 10−3 mg mL−1 with a detection limit of 6.12 × 10−8 mg mL−1 (3σ). The proposed electrochemical sensor was used to detect OLA in swine samples at a recovery ranging from 97.78% to 104.25%, which exhibits a broader prospect to supervise animal products and a high potential for food security applications.
危险品化学品经营许可证（带存储）