基于SNW-1磁性固相萃取牛奶中磺胺类药物

SNW-1 Magnetic Solid Phase Extraction for HPLC Detection of Sulfonamides Residue in Milk

【目的】制备磁性共价有机骨架材料(Fe3O4@SNW-1)作为磁性固相萃取吸附剂,建立牛奶中磺胺类药物(SAs)的高效液相色谱(HPLC)测定方法。【方法】通过水热法合成Fe3O4@SNW-1,并通过研究吸附剂用量、吸附时间、洗脱剂、洗脱时间等影响因素,优化磁性固相萃取磺胺类药物的回收率,最后通过高效液相色谱法(HPLC)检验优化后方法的效果。【结果】优化后的MSPE条件:即用2.0 mL氨水-甲醇(5∶95,v/v)作为洗脱溶剂,解吸时间设为60 s,吸附剂Fe3O4@SNW-1的用量为4.0 mg,吸附时间为120 s,pH值为6.0。经优化后,5种SAs的线性范围为10~100 ng·mL^-1,相关系数在0.995以上,检出限为1.7~2.7 ng·mL^-1。5种SAs(每种50 ng·mL^-1)的5次重复提取的日间RSDs为2.8%~4.7%。5种SAs的回收率在72.0%~95.0%【结论】该方法方便快捷,选择性好,分离效果高,对牛奶中痕量磺胺类药物含量的检测效果良好。

【Objective】 Fe3O4@SNW-1 was prepared as an adsorbent in the magnetic solid phase extraction(MSPE) to pretreat samples for HPLC determination on sulfonamides(SAs) in milk.【Method】 A magnetic covalent organic framework(COF) material, Fe3 O4@SNW-1, was hydrothermally synthesized to serve as the adsorbent in MSPE for the sample pretreatment. Parameters for the pretreatment, including adsorbent usage, adsorption duration, eluent selection, and elution time that affected the extract recovery, were optimized. HPLC was used to evaluate and determine the validity of the methodology.【Result】 The optimized MSPE applying 2.0 mL ammonia-methanol(5∶95, V/V) as elution solvent, 60 s for desorption, 4.0 mg of Fe3 O4@SNW-1 as adsorbent, 120 s for adsorption at pH 6.0 to achieve linearities in the ranges between10 ng·mL^-1 and 100 ng·mL^-1 on detecting 5 different SAs with correlation coefficients greater than 0.995. The HPLC detection limit on the SAs was 1.7-2.7 ng·mL^-1. The daytime RSDs of 5 extraction replicates on the SAs(50 ng·mL^-1 each) were2.8–4.7%. The recovery rates on the SAs varied from 72.0% to 95.0%. 【Conclusion】 The proposed HPLC method with the MSPE sample pretreatment was convenient, rapid, specific, and effective for the determination of trace amounts of SA residues in milk.