建立了一种以液相微萃取为样品前处理技术,结合高效液相色谱快速、有效测定唾液中尼古丁含量的方法.确定了以磷酸三丁酯为有机溶剂、 2 mL 0.05 mol/L KOH调节2 mL样品溶液为给出相, 10 mmol/L KH2PO4(pH=3.0)为接收相;搅拌速率为500 r/min, 萃取时间为17 min的尼古丁优化萃取条件.方法的线性范围0.1~50 mg/L,相关系数r^2 = 0.9996;检出限为0.05 mg/L (S/N=3 );相对标准偏差<5% (n = 5);相对回收率为96.3%~102.2%.实验证明该法可用于唾液等生物体液中碱性物质的测定.
A rapid, effective and environmentally friendly method to determine nicotine in saliva by HPLC with liquid phase microentraction (LPME) as sample preparation technique was introduced. The significant parameters affecting the LPME performance such as selection of microextraction solvent, extraction time, stirring rate, pH of sample solution and acceptor phase, and ionic strength were studied and optimized. The opti- mum experimental conditions were as follows found: tri-n-butylphosphate as organic solvent, 17 inin extraction time, 500 r/rain stirring rate, 2 mL 0.05 mol/L KOH to adjust the sample pH, acceptor phase pH = 3 and no salt addition. Under the optimum conditions, the proposed method provided linear range of 0.1 -50 mg/L with r^2 =0.9996, detection limit of 0.05 mg/L ( S/N = 3 ), RSD 〈 5% ( n = 5 ) and relative recovery of 96.3% - 102.2%.