Skok Arina, Vishnikin Andriy, Bazel Yaroslav
Department of Analytical Chemistry, Institute of Chemistry, Faculty of Science, University of Pavol Jozef Šafárik in Košice Moyzesova 11 040 01 Košice Slovak Republic.
Department of Analytical Chemistry, Faculty of Chemistry, Oles Honchar Dnipro National University Gagarin Av. 72 49010 Dnipro Ukraine
RSC Adv. 2022 Jun 15;12(28):17675-17681. doi: 10.1039/d2ra01010k. eCollection 2022 Jun 14.
A new design for headspace liquid phase microextraction in combination with an optical immersion probe (HS-LPME-OIP) was proposed and successfully tested for the determination of sulfide in wine and water samples. The developed method is based on the release of hydrogen sulfide from the aqueous phase after the addition of orthophosphoric acid and its extraction with an aqueous solution of 5,5'-dithiobis-(2-nitrobenzoic) acid (DTNB). The analytical signal was recorded using an optical probe immersed in a vial containing 200 μL of 0.1 mM DTNB solution. Using the optical immersion probe in combination with HS-LPME allowed to register the analytical signal online and significantly improve the reproducibility of sulfide determination compared to known microextraction approaches. In the proposed approach, the problems with drop stability, limitations in mixing rate or extraction time, too small volume of the acceptor phase and stability of the holding the acceptor phase in the hole of the optical probe were also satisfactorily solved. The calibration graph was linear in the range of 16-256 μg L with a correlation coefficient of 0.9992. The limit of detection was 6 μg L.
提出了一种结合光学浸入式探头的顶空液相微萃取新设计（HS-LPME-OIP），并成功用于葡萄酒和水样中硫化物的测定。所开发的方法基于加入正磷酸后水相中硫化氢的释放，以及用5,5'-二硫代双（2-硝基苯甲酸）（DTNB）水溶液对其进行萃取。使用浸入装有200 μL 0.1 mM DTNB溶液的小瓶中的光学探头记录分析信号。与已知的微萃取方法相比，将光学浸入式探头与HS-LPME结合使用能够在线记录分析信号，并显著提高硫化物测定的重现性。在所提出的方法中，还令人满意地解决了液滴稳定性问题、混合速率或萃取时间的限制、接受相体积过小以及在光学探头孔中保持接受相的稳定性等问题。校准曲线在16 - 256 μg/L范围内呈线性，相关系数为0.9992。检测限为6 μg/L。
