四磺基镍酞菁-Pb(II)光学探针对水相三聚磷酸根的高特异性响应研究

Study on High Specific Response of Tetrasulfonyl Nickel Phthalocyanine-Pb(II) Optical Probe to Triphosphate in Aqueous Phase

摘要: 通过四磺酸镍酞菁(镍4,4’,4’-四磺基酞菁，NiS4Pc)与一系列阳离子的水相反应发现，NiS4Pc可与Pb2+形成不溶性化合物，而多种阴离子可将其溶解。进一步发现，酸性物质(酸抑制剂)的存在可以抑制阴离子对该化合物的溶解作用。对酸抑制剂的筛选获得了重要的发现：在低浓度柠檬酸存在下，绝大多数阴离子对沉淀的溶解作用被完全或显著抑制，只有P₃O^5-₁₀仍然可以溶解沉淀化合物NiS4Pc-Pb(II)，使NiS4Pc被释放至溶液中，溶液相显示出NiS4Pc Pb(II)的特征颜色和吸收光谱，从而为P₃O^5-₁₀提供了高特异性的光学探针。溶液的颜色和吸收强度可长期保持稳定，表明这一光学探针具有显著的稳定性。基于这一发现，本研究建立了一种新的光度分析法，用于高特异性定量检测水相中的P₃O^5-₁₀。对实验参数进行了优化，在最佳条件下，吸光度差(ΔA621)与P₃O^5-₁₀浓度在3.075.0 µg/mL范围内表现出良好的线性相关。回归方程为ΔA621 = 0.014C − 0.057，r = 0.9984。检测限为2.0 µg/mL。与传统的P₃O^5-₁₀检测方法相比，该方法具有特异性高、稳定性好、操作简便、快速等特点，具有很强的应用前景。此法还可用于目视化检测，这对于现场或现场分析特别有益。本研究提出了阴离子检测新原理，开拓了金属酞菁化合物在分析科学中的新应用。

Abstract: A series of reactions between cationic ions and nickel tetrasulfonated phthalocyanine (nickel 4,4’,4’,4’-tetrasulfophthalocyanine, NiS4Pc) were performed and demonstrated that water-soluble NiS4Pc can complex with Pb2+ to form an insoluble compound, many acid anions can dissolve this compound. However, the presence of acidic materials (acid inhibitors) can inhibit the dissolution of this compound by acid anions. Screening of acid inhibitors led to an important finding. In the presence of a low concentration of citric acid, the precipitate dissolution by most anions was completely or significantly inhibited; only P₃O^5-₁₀ could still dissolve the precipitate compound, NiS4Pc- Pb(II), to release NiS4Pc. The solution phase shows the characteristic color and absorption spectroscopy of NiS4Pc-Pb(II), thus providing a specific optical probe for P₃O^5-₁₀. In addition, the color and absorption intensity of the solution remained stable for a long time (more than three months), indicating significant stability of the optical probe. Based on this finding, a new spectrophotometric technique has been established for detecting and quantifying aqueous P₃O^5-₁₀ with high specificity. Furthermore, a new model for the visual (naked eye) detection of P₃O^5-₁₀ has been developed. The experimental parameters have been optimized. Under the optimal conditions, the absorbance difference (ΔA621) shows an excellent linear correlation with the P₃O^5-₁₀ concentration (C, µg/mL) ranging from 3.0~75.0 µg/mL. The linear regression equation is ΔA621 = 0.014C − 0.057, with r = 0.9984. The limit of detection was 2.0 µg/mL. Compared to traditional P₃O^5-₁₀ detection methods, this method exhibits high specificity, excellent stability, easy and fast operation and thus strong application potential. This method can provide visual detection, which will be particularly beneficial for in situ or field analyses. In this study, the preparation of metal phthalocyanine insoluble compound optical probe for highly selective determination of P₃O^5-₁₀ is universal in principle. It is expected that more optical probes could be constructed based on this principle and applied to the detection of other sorts of anions.