College of Chemistry and Pharmaceutical Sciences , Qingdao Agricultural University , Qingdao 266109 , China.
Department of Chemistry, Waterloo Institute for Nanotechnology , University of Waterloo , Waterloo , Ontario N2L 3G1 , Canada.
Langmuir. 2018 Dec 26;34(51):15871-15877. doi: 10.1021/acs.langmuir.8b03335. Epub 2018 Dec 17.
Chemical reactions without an obvious optical signal change, such as fluorescence or color, are difficult to monitor. Often, more advanced analytical techniques such as high-performance liquid chromatography and mass spectroscopy are needed. It would be useful to convert such reactions to those with changes in optical signals. In this work, we demonstrate that fluorescently labeled DNA oligonucleotides adsorbed on nanomaterials can probe such reactions, and oxidation of phosphorus-containing species was used as an example. Various metal oxides were tested, and CeO nanoparticles were found to be the most efficient for this purpose. Among phosphate, phosphite, and hypophosphite, only phosphate produced a large signal, indicating its strongest adsorption on CeO to displace the DNA. This was further used to screen oxidation agents to convert lower oxidation-state compounds to phosphate, and bleach was found to be able to oxidize phosphite. Canonical discriminant analysis was performed to discriminate various phosphorus species using a sensor array containing different metal oxides. On the basis of this, glyphosate was studied for its adsorption and oxidation. Although this method is not specific enough for selective biosensors, it is useful as a tool to produce sensitive optical signals to follow important chemical transformations.
没有明显光学信号变化的化学反应，如荧光或颜色变化，很难进行监测。通常需要更先进的分析技术，如高效液相色谱和质谱。将这些反应转化为具有光学信号变化的反应将是很有用的。在这项工作中，我们证明了吸附在纳米材料上的荧光标记 DNA 寡核苷酸可以探测到这种反应，并以含磷物种的氧化为例。我们测试了各种金属氧化物，发现 CeO 纳米颗粒在这方面最有效。在磷酸盐、亚磷酸盐和次磷酸盐中，只有磷酸盐产生了很大的信号，表明它在 CeO 上的吸附最强，从而取代了 DNA。这进一步用于筛选氧化剂，将较低氧化态的化合物转化为磷酸盐，发现漂白剂能够氧化亚磷酸盐。使用包含不同金属氧化物的传感器阵列对各种磷物种进行了典型判别分析。在此基础上，研究了草甘膦的吸附和氧化。尽管这种方法对于选择性生物传感器来说不够特异，但它作为一种产生敏感光学信号以跟踪重要化学转化的工具是很有用的。
