| Abstrakt: |
Reducing substances play crucial roles in various physiological processes and serve as essential components in the antioxidant defense mechanisms within organisms. Nonetheless, accurately detecting and distinguishing between these substances present a notable challenge due to the presence of potential interferences in complex samples. In response to this challenge, a novel multisignal sensing platform and sensor array have been developed, leveraging fluorescent polydopamine nanoparticles (FPDA) and MnO2 nanozyme. The MnO2/FPDA nanoplatform possesses exceptional catalytic activity and the ability to modulate ratiometric fluorescence in the presence of o-phenylenediamine (OPD), offering a platform with dual-channel output signals in ratiometric fluorescence and UV absorbance. Upon introduction of H2O2, the MnO2 undergoes transformation into Mn2+, thereby reducing the oxidase-like activity of MnO2 and reinstating the fluorescence of FPDA. Notably, this platform exhibits detection ranges for H2O2 from 5 to 500 and 15 to 500 μM, with corresponding detection limits of 3.18 and 10.67 μM using fluorescence and colorimetric channels, respectively. This setup has been deployed for quantifying H2O2 in milk and cell lysates, showcasing its versatility as a universal analysis tool for other reducing agents like ascorbic acid. Furthermore, a sensor array has been developed based on MnO2/FPDA/OPD, demonstrating a robust capacity to effectively differentiate and identify five reducing agents effectively. This sensor array also exhibits strong performance in discriminating reducing substances within intricate or authentic samples, such as oranges and cell lysates, underscores its practical utility. This study offers significant insights into the development of sensing platforms for the selectively detecting specific reducing species in real samples or deploying sensor arrays for distinguishing multiple components within authentic samples. Such advancements pave the way for enhanced analysis and screening of reducing substances in cellular and food samples. [ABSTRACT FROM AUTHOR] |
