Vera-Candioti L, Gil García M D, Martínez Galera M, Goicoechea H C
Laboratorio de Desarrollo Analítico y Quimiometría (LADAQ), Cátedra de Química Analítica I, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Ciudad Universitaria, Santa Fe (S3000ZAA), Argentina.
J Chromatogr A. 2008 Nov 21;1211(1-2):22-32. doi: 10.1016/j.chroma.2008.09.093. Epub 2008 Oct 2.
In the present work, an analytical method for the simultaneous determination of seven non steroidal anti-inflammatory drugs (naproxen, ketoprofen, diclofenac, piroxicam, indomethacin, sulindac and diflunisal) and the anticonvulsant carbamazepine is reported. The method involves preconcentration and clean-up by solid-phase microextraction using polydimethylsiloxane/divinylbenzene fibers, followed by liquid chromatography with diode array detection analysis. Parameters that affect the efficiency of the solid-phase microextraction step such as soaking solvent, soaking period, desorption period, stirring rate, extraction time, sample pH, ionic strength, organic solvent and temperature were investigated using a Plackett-Burman screening design. Then, the factors presenting significant positive effects on the analytical response (soaking period, stirring rate, stirring time) were considered in a further central composite design to optimize the operational conditions for the solid phase microextraction procedure. Additionally, multiple response simultaneous optimization by using the desirability function was used to find the optimum experimental conditions for the on-line solid-phase microextraction of analytes in river water samples coupled to liquid chromatography and diode array detection. The best results were obtained using a soaking period of 5 min, stirring rate of 1400 rpm and stirring time of 44 min. The use of solid-phase microextraction technique avoided matrix effect and allowed to quantify the analytes in river water samples by using Milli-Q based calibration graphs. Recoveries ranging from 71.6% to 122.8% for all pharmaceuticals proved the accuracy of the proposed method in river water samples. Method detection limits were in the range of 0.5-3.0 microgL(-1) and limits of quantitation (LOQs) were between 1.0 and 4.0 microgL(-1) for pharmaceutical compounds in river water samples. The expanded uncertainty associated to the measurement of the concentration ranged between 8.5% and 29.0% for 20 microgL(-1) of each analyte and between 9.0% and 29.5% for the average of different concentration levels. The main source of uncertainty was the calibration step in both cases.
在本研究中，报道了一种同时测定七种非甾体抗炎药（萘普生、酮洛芬、双氯芬酸、吡罗昔康、吲哚美辛、舒林酸和二氟尼柳）以及抗惊厥药卡马西平的分析方法。该方法包括使用聚二甲基硅氧烷/二乙烯基苯纤维通过固相微萃取进行预浓缩和净化，随后进行配有二极管阵列检测分析的液相色谱分析。采用Plackett-Burman筛选设计研究了影响固相微萃取步骤效率的参数，如浸泡溶剂、浸泡时间、解吸时间、搅拌速率、萃取时间、样品pH值、离子强度、有机溶剂和温度。然后，在进一步的中心复合设计中考虑了对分析响应呈现显著积极影响的因素（浸泡时间、搅拌速率、搅拌时间），以优化固相微萃取程序的操作条件。此外，使用合意函数进行多响应同时优化，以找到河流水样中分析物在线固相微萃取与液相色谱和二极管阵列检测联用的最佳实验条件。在浸泡时间为5分钟、搅拌速率为1400转/分钟和搅拌时间为44分钟时获得了最佳结果。固相微萃取技术的使用避免了基质效应，并允许通过基于超纯水校准曲线对河流水样中的分析物进行定量。所有药物的回收率在71.6%至122.8%之间，证明了该方法在河流水样中的准确性。河流水样中药物化合物的方法检测限在0.5 - 3.0微克/升范围内，定量限（LOQs）在1.0至4.0微克/升之间。对于每种分析物20微克/升的浓度测量，扩展不确定度在8.5%至29.0%之间，对于不同浓度水平的平均值，扩展不确定度在9.0%至29.5%之间。在这两种情况下，不确定度的主要来源都是校准步骤。
