Abstract

The development of efficient methods for alkaline phosphatase (ALP) activity assay is of great importance in clinical diagnosis and many biomedical applications. In this work, the authors create two strategies for colorimetric detection of ALP activity. The first strategy is developed by using directly manganese dioxide (MnO₂) nanosheets as colorimetric probes. The second strategy is developed by using MnO₂ and the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) as colorimetric probes based on the catalytic reduction of oxidized TMB. The first strategy has a linear response in 10 U L⁻¹ to 80 U L⁻¹ with 3.0 U L⁻¹ detection limit while the second one has a linear response in 7 U L⁻¹ to 100 U L⁻¹ with 0.05 U L⁻¹ detection limit. The method based on MnO₂-TMB which have lower detection limit and higher sensitivity was applied to monitor ALP activity in whole Hela cells lysate. In addition, based on redox properties, MnO₂-TMB sensing system was successfully used in detecting reducing substances such as ascorbic acid, Na₂S and so forth. Conceivably, MnO₂-TMB sensing system is not limited to ALP activity assay but has a wide scope to be applied in assays of the total antioxidant capacity of dietary substances and biological fluids.

Graphic Abstract

Two strategies were created for colorimetric detection of ALP activity: The first strategy is developed by using directly manganese dioxide (MnO₂) nanosheets as colorimetric probes, and the second strategy by using MnO₂ and the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) as colorimetric probes based on the catalytic reduction of oxidized TMB.

中文翻译：

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基于MnO 2纳米片的比色传感平台，用于检测整个Hela细胞中的还原性物质和碱性磷酸酶活性

摘要

碱性磷酸酶（ALP）活性测定的有效方法的开发在临床诊断和许多生物医学应用中非常重要。在这项工作中，作者创建了两种比色检测ALP活性的策略。通过直接使用二氧化锰（MnO ₂）纳米片作为比色探针来开发第一种策略。第二种策略是通过使用MnO ₂和发色底物3,3'，5,5'-四甲基联苯胺（TMB）作为比色探针，基于氧化TMB的催化还原而开发的。第一种策略的线性响应范围为10 U L ^-1至80 U L ^-1，检测极限为3.0 U L ^-1，第二种策略的线性范围为7 U L ^-1至100 U L ^-1，检测极限为0.05 U L ^-1。采用检测限较低，灵敏度较高的基于MnO ₂ -TMB的方法监测整个Hela细胞裂解液中的ALP活性。此外，基于氧化还原特性，MnO ₂ -TMB传感系统已成功用于检测还原性物质，例如抗坏血酸，Na ₂ S等。可以想象，MnO ₂ -TMB传感系统不仅限于ALP活性测定，还具有广泛的应用范围，可用于测定膳食物质和生物流体的总抗氧化能力。

图形摘要

创建了两种比色检测ALP活性的策略：第一种策略是直接使用二氧化锰（MnO ₂）纳米片作为比色探针，第二种策略是使用MnO ₂和生色底物3,3'，5,5 '-四甲基联苯胺（TMB）作为比色探针，基于氧化的TMB的催化还原。