Highly Active Oxidase-like N-Mn₃O₄ Nanoparticles from Amino Acid Nitrogen Source for Dual-Mode Detection of Acid Phosphatase

Abstract

Defect-engineered nanomaterials have been found to improve catalytic activity, making them highly desirable for biosensor preparation. Nitrogen doping is an effective method for introducing defects in nanomaterials, and amino acids containing nitrogen atoms can be used as a nitrogen source for doping nanozymes. In this study, nitrogen-doped N-Mn 3 O 4 nanoparticles (NPs) were synthesized using various amino acids as nitrogen sources. The results indicate that N-Mn 3 O 4 NPs doped with histidine as a nitrogen source exhibit the highest oxidase-like activity. Additionally, N-Mn 3 O 4 NPs have a V max that is 5.4-fold higher and a K m that is 1/2-fold lower than Mn 3 O 4 , suggesting that histidine-doped N-Mn 3 O 4 NPs can be used to create highly active oxidase-like enzymes. A dual-modal sensor utilizing both ratiometric fluorescence and smartphone-based colorimetry method with a smartphone has been developed for the detection of acid phosphatase, based on N-Mn 3 O 4 NPs with high enzymatic activity. This study presents an approach to constructing highly active oxidase-like and realizing a highly sensitive assay for detecting acid phosphatase with high interference resistance. The mechanisms underlying the improved performance of nitrogen-doped nanomaterials and their potential applications in biosensor fields were also discussed.

Graphitic Carbon Nitride/V3O7 Nanocomposites with Antibacterial Property via Photocatalytic and Nanozyme Activities

“…Subsequently, the mechanism of ROS generation by VCN synergized with photocatalysis and nanozyme catalysis under visible light was explored. Benzoquinone (BQ), isopropanol (IPA), methanol (MeOH), and CuCl 2 were used as scavengers for the capture of O 2 •– , •OH, h + , and e – , respectively. , As can be seen in Figure F, both BQ and IPA inhibited the system better, suggesting that O 2 •– and •OH are the main ROS generated by VCN synergistic photocatalysis and nanozyme catalysis. However, both MeOH and CuCl 2 improved the system.…”

Rational Integration of Nanozyme Probe and Smartphone Device for On‐Site Analysis

“…In fact, to achieve better selectivity and accuracy, nanozyme-smartphone integrated sensing platforms with dual-signal output modes instead of only one output signal were proposed, in which colorimetric-electrochemical, colorimetric-fluorescence and colorimetric-Raman scattering have been reported. [79][80][81] Recently, multiple machine learning algorithms have been exploited to help constructing nanozyme-based sensors. [82][83][84] By virtue of machine learning, nanozyme sensors with polytype of output signals, meanwhile the signals could be processed simultaneously within one smartphone, are highly expected, yet underdeveloped.…”

“…Using histidine-doped NÀ Mn 3 O 4 NPs with OXD-like activity, Yue and co-workers proposed a dual-mode detection method for ACP content based on colorimetric and ratiometric fluorescence methods with a smartphone. [116] The AA produced from the hydrolysis of ACP by AAP decreased the oxidation degree of TMB, leading to the depigmentation of blue oxTMB, followed by using the "Color Picker" App on a smartphone to collect the RGB values. On the other hand, NÀ Mn 3 O 4 NPs catalyzed the oxidization of AA to generate dehydrogenous ascorbic acid (DHAA).…”

“…Consequently, it is also of great significance to monitor ACP for early diagnosis of related diseases. Using histidine‐doped N−Mn 3 O 4 NPs with OXD‐like activity, Yue and co‐workers proposed a dual‐mode detection method for ACP content based on colorimetric and ratiometric fluorescence methods with a smartphone [116] . The AA produced from the hydrolysis of ACP by AAP decreased the oxidation degree of TMB, leading to the depigmentation of blue oxTMB, followed by using the “Color Picker” App on a smartphone to collect the RGB values.…”

Ultrasmall CuMn-His Nanozymes with Multienzyme Activity at Neutral pH: Construction of a Colorimetric Sensing Array for Biothiol Detection and Disease Identification

“…In comparison with MnOOH, the binding energy of the Mn 2p orbital in CuMn-His was observed to shift toward lower energy levels (Figure 1G), indicating a reduction in the valence state of Mn within CuMn-His. 31 The Mn 2p 3/2 spectrum can be deconvoluted into three distinct binding energy peaks. Specifically, the peaks at 640.7 and 639.6 eV are assigned to Mn 2+ , while those at 641.0 and 641.8 eV are attributed to Mn 3+ .…”