Institute of High Technologies, Taras Shevchenko National University of Kyiv, 64 Volodymyrska, 01601 Kyiv, Ukraine.
Institute of High Technologies, Taras Shevchenko National University of Kyiv, 64 Volodymyrska, 01601 Kyiv, Ukraine.
Biosens Bioelectron. 2015 Apr 15;66:89-94. doi: 10.1016/j.bios.2014.10.075. Epub 2014 Nov 5.
A phenomenon of changes in photoluminescence of porous silicon at variations in medium pH is proposed to be used as a basis for the biosensor system development. The method of conversion of a biochemical signal into an optical one is applied for direct determination of glucose and urea as well as for inhibitory analysis of heavy metal ions. Changes in the quantum yield of porous silicon photoluminescence occur at varying pH of the tested solution due to the enzyme-substrate reaction. When creating the biosensor systems, the enzymes urease and glucose oxidase (GOD) were used as a bioselective material; their optimal concentrations were experimentally determined. It was shown that the photoluminescence intensity of porous silicon increased by 1.7 times when increasing glucose concentration in the GOD-containing reaction medium from 0 to 3.0mM, and decreased by 1.45 times at the same increase in the urea concentration in the urease-containing reaction medium. The calibration curves of dependence of the biosensor system responses on the substrate concentrations are presented. It is shown that the presence of heavy metal ions (Cu(2+), Pb(2+), and Cd(2+)) in the tested solution causes an inhibition of the enzymatic reactions catalyzed by glucose oxidase and urease, which results in a restoration of the photoluminescence quantum yield of porous silicon. It is proposed to use this effect for the inhibitory analysis of heavy metal ions.
提出了多孔硅的光致发光在介质 pH 值变化时发生变化的现象，可作为生物传感器系统开发的基础。应用将生化信号转换为光学信号的方法，直接测定葡萄糖和尿素，并对重金属离子进行抑制性分析。由于酶-底物反应，多孔硅光致发光的量子产率在测试溶液的 pH 值变化时发生变化。在创建生物传感器系统时，使用脲酶和葡萄糖氧化酶（GOD）作为生物选择性材料；通过实验确定了它们的最佳浓度。结果表明，当 GOD 存在的反应介质中葡萄糖浓度从 0 增加到 3.0mM 时，多孔硅的光致发光强度增加了 1.7 倍，而在含有脲酶的反应介质中，尿素浓度相同增加时，光致发光强度降低了 1.45 倍。给出了生物传感器系统响应与底物浓度之间的依赖关系的校准曲线。结果表明，在测试溶液中存在重金属离子（Cu(2+)、Pb(2+)和 Cd(2+)）会抑制葡萄糖氧化酶和脲酶催化的酶反应，导致多孔硅的光致发光量子产率恢复。提出利用这种效应进行重金属离子的抑制性分析。
Zotero 插件