Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China.
Analyst. 2017 Oct 9;142(20):3986-3992. doi: 10.1039/c7an01293d.
We herein report the intrinsic alkaline peroxidase-like activity exhibited by CuO nanoparticles when 3-(4-hydroxyphenyl)propionic acid was employed as a substrate. Based on this observation, a fluorometric assay method with a low detection limit of 0.81 μM was established for HO determination under alkaline conditions. Notably, ammonia was found to inhibit the alkaline peroxidase-like activity of the CuO nanoparticles. Thus, a sensing platform for the determination of urea and urease was successfully constructed, with the limits of detection for urea and urease being 27 μM and 2.6 U L, respectively. This platform was then applied for the detection of urea in human urine and urease in soil, which yielded satisfactory results. These results suggest that it is possible to extend the catalytic potential of peroxidase and its mimetics from acidic and neutral conditions to include activity in alkaline media as well. Furthermore, this strategy is a novel method for the analysis of urea and urease. The assay developed in this work is facile, inexpensive, convenient, and highly selective and sensitive. Therefore, it is expected that this system can serve as a template for the development of similar enzyme nano-mimics.
我们在此报告了当 3-(4- 羟基苯基)丙酸被用作底物时，氧化铜纳米粒子表现出的固有碱性过氧化物酶样活性。基于这一观察结果，建立了一种在碱性条件下用于 HO 测定的荧光分析方法，其检测限低至 0.81 μM。值得注意的是，氨被发现抑制了氧化铜纳米粒子的碱性过氧化物酶样活性。因此，成功构建了用于测定尿素和脲酶的传感平台，尿素和脲酶的检测限分别为 27 μM 和 2.6 U L。然后，该平台被用于检测人尿中的尿素和土壤中的脲酶，得到了令人满意的结果。这些结果表明，有可能将过氧化物酶及其模拟物的催化潜力从酸性和中性条件扩展到包括碱性介质中的活性。此外，该策略是分析尿素和脲酶的一种新方法。本工作中开发的测定方法简便、廉价、方便且具有高度选择性和灵敏度。因此，预计该系统可以作为开发类似酶纳米模拟物的模板。
