Abstract：
The use of an optical probe for fluorescence detection combined with direct immersion single-drop microextraction has been demonstrated as an innovative approach. The optical probe served both as a drop holder for extractant and as a measuring device which made it possible to eliminate the use of cuvettes. A laser and a light emitting diode (LED) were tested as possible light sources. Both of them showed comparable results. However, given the much smaller half-band width of the laser radiation, its use has proven to be preferable since background correction can be eliminated. Direct immersion single-drop microextraction of an ionic association complex of rhodamine 6G with picric acid with subsequent fluorescent detection (λex was 532 nm and 525 nm for laser and LED, respectively; λem was 560 nm for both laser and LED) was used a model system to evaluate the new approach. The extractant phase was a 55 μL amyl acetate microdrop fixed in the optical part of the probe. LOD, LOQ and linear calibration range were found as 0.14, 0.48 and 0.5-10 nmol L-1, and 0.15, 0.50 and 0.5-5 nmol L-1 for laser and LED light sources, respectively. The accuracy of the method was assessed by analyzing real water samples.
摘要：
使用光学探针进行荧光检测与直接浸入式单滴微萃取相结合已被证明是一种创新方法。光学探针既用作萃取剂的滴架，又用作测量装置，可以消除比色皿的使用。测试激光器和发光二极管(LED)作为可能的光源。两者都显示出相当的结果。然而,考虑到激光辐射的半带宽要小得多，它的使用已被证明是优选的，因为背景校正可以消除。直接浸入式单滴微萃取罗丹明6G与苦味酸的离子缔合络合物，随后进行荧光检测（激光和LED的λex为532nm和525nm，分别；激光和LED的λem均为560nm）使用模型系统来评估新方法。萃取相是固定在探针光学部分中的55μL乙酸戊酯微滴。LOD,激光和LED光源的LOQ和线性校准范围分别为0.14、0.48和0.5-10nmolL-1，0.15、0.50和0.5-5nmolL-1，分别。通过分析实际水样来评估该方法的准确性。
