College of Chemistry and Material Science, Sichuan Normal University, Chengdu, Sichuan, 610068, China.
College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637000, China.
Talanta. 2020 Nov 1;219:121387. doi: 10.1016/j.talanta.2020.121387. Epub 2020 Jul 9.
In view of the high sensitivity and good selectivity, chemical vapor generation atomic spectrometry (CVG-AS) and inductively coupled plasma mass spectrometer (ICP-MS), especially low-cost atomic fluorescence spectrometry (AFS) have been widely used in bioassay. However, the existing AS method is mostly based on heterogeneous strategies, and can't detect multiple targets in one system. In this study, we present the discovery and mechanism study of a phenomenon of Hg pre-reduction that the concentration of Hg decreased when it was mixed with the reductants (ascorbic acid (AA), SnCl, or NaBH/KBH) over long-time reaction (hours) by CVG-AFS and ICP-MS. A homogeneous Cu assay method was developed based on the competition reaction of Cu and Hg for consuming AA, and its application in the detection of pyrophosphate (PPi) and alkaline phosphatase (ALP) was investigated based on the PPi complexation with Cu, and ALP hydrolyzation of PPi using CVG-AFS as a representative detector. Subsequently, in order to further verify the applicability of the system, cation exchange reaction (CER) was utilized here based on the selectively recognize Ag and C-Ag-C by CuS nanoparticles (NPs). As the exchanged Cu from CuS NPs can be sensitively and selectively detected via above-mentioned Cu assay method, this strategy can be extended for the Ag, DNA and prostate specific antigen (PSA) detection based on base complementary pairing and the specific recognition of aptamer. Under the optimal experimental conditions, the system showed high sensitivity for the detection of Cu, PPi, ALP, Ag, DNA, and PSA, with limit of detections (LODs) of 0.12 nmol L, 25 μmol L, 0.025 U/L, 0.2 nmol L, 0.05 nmol L, and 0.03 ng/mL, respectively. The method was successfully used to determination Cu, ALP, and PSA in human serums, showing similar results with those of ICP-MS and kits methods.
鉴于其高灵敏度和良好的选择性，化学蒸气发生原子光谱法（CVG-AS）和电感耦合等离子体质谱法（ICP-MS），特别是低成本原子荧光光谱法（AFS）已被广泛应用于生物测定中。然而，现有的 AS 方法大多基于异质策略，无法在一个系统中同时检测多个目标。在本研究中，我们发现并研究了一种现象，即 CVG-AFS 和 ICP-MS 表明，当汞与还原剂（抗坏血酸（AA）、SnCl2 或 NaBH4/KBH4）长时间（数小时）混合时，汞的浓度会降低。基于 Cu 与 Hg 对 AA 的消耗竞争反应，建立了一种均相 Cu 测定方法，并以 CVG-AFS 为代表的检测器，研究了其在焦磷酸盐（PPi）和碱性磷酸酶（ALP）检测中的应用，基于 PPi 与 Cu 的络合，以及 ALP 对 PPi 的水解。随后，为了进一步验证该体系的适用性，本研究利用基于 CuS 纳米粒子（NPs）对 Ag 和 C-Ag-C 的选择性识别的阳离子交换反应（CER）。由于从 CuS NPs 中交换出的 Cu 可以通过上述 Cu 测定方法进行灵敏且选择性检测，因此该策略可进一步扩展到基于碱基互补配对和适体特异性识别的 Ag、DNA 和前列腺特异性抗原（PSA）检测中。在最佳实验条件下，该体系对 Cu、PPi、ALP、Ag、DNA 和 PSA 的检测具有较高的灵敏度，检测限（LOD）分别为 0.12 nmol·L-1、25 μmol·L-1、0.025 U/L、0.2 nmol·L-1、0.05 nmol·L-1 和 0.03 ng/mL。该方法成功地用于人血清中 Cu、ALP 和 PSA 的测定，与 ICP-MS 和试剂盒方法的结果相似。
