Label-Free, Reusable, Equipment-Free, and Visual Detection of Hydrogen Sulfide Using a Colorimetric and Fluorescent Dual-Mode Sensing Platform

Abstract

In this work, we have found for the first time that the fluorescence of rhodamine B (RhB) would be dramatically reduced after it bound to hemin/G-quadruplex and reacted with •OH. Based on this finding, we have designed a colorimetric and fluorescent dual-mode sensing platform for visual detection of hydrogen sulfide (H2S). The constructed sensor is based on the formation of dsDNA and the G-quadruplex structure by the cytosine-Ag+-cytosine mismatch, causing H2O2-mediated catalysis to oxidize ABTS or RhB to induce a colorimetric or fluorescent change. In the presence of H2S, the solution color for colorimetric and fluorescent assays would change from dark green to pink and from green (fluorescence off) to bright yellow (fluorescence on), respectively. This dual-mode assay showed high selectivity toward H2S over other interference materials with a low measurable detection limit value (below than 2.5 μM), and it has been successfully applied to H2S visual detection in real samples. Moreover, the dual-mode sensing strategy presented an excellent reutilization character both in colorimetric and fluorescent assays. This method was employed as a label-free, simple, fast, and equipment-free platform for H2S detection with high selectivity and reusability. This work realized naked-eye detection both in colorimetric and fluorescent analysis at a lower concentration of H2S, demonstrating a promising strategy for on-site visual detection of H2S.

Recent Advances in the DNA-Mediated Multi-Mode Analytical Methods for Biological Samples

“…G-quadruplex is a special high-level structural DNA sequence formed by the tandem folding of large numbers of oligonucleotides or deoxyribonucleotide sequences that are rich in repeated guanine G [72]. Due to the different structural information and folding paths of G-quadruplex, it can not only guide the synthesis of nanoprobes but also carry out self-assembly recognition response to the target by virtue of its driving effect, which is usually used to construct multi-mode probes with excellent specificity and sensitivity [73]. Since G-quadruplex has abundant guanine G bases with the special coordination effect for K + ions, it can selectively recognize K + and spontaneously form a structurally stable G-quadruplex DNAzyme with Hemin (HM) via the DNA self-assembly method [74].…”

A Self‐Accelerating Naphthalimide‐Based Probe Coupled with Upconversion Nanoparticles for Ultra‐Accurate Tri‐Mode Visualization of Hydrogen Peroxide

“…One efficient strategy to break this bottleneck is to construct a dual‐mode visualization detection platform with two independent signals, such as the colorimetric‐fluorescent dual‐mode detection. [ 23 , 24 ] A series of studies proved that fluorophores, such as rhodamine‐based compounds, [ 25 ] 1,8‐naphthalimide derivatives, [ 26 ] cyanine derivatives, [ 27 ] and bodipy‐based derivatives, [ 28 ] can be used for it. In addition, nanoparticles modified with organic small‐molecule fluorescent probes, such as QDs, [ 29 ] metal‐based nanoparticles, [ 30 ] and MOFs, [ 31 ] have been introduced to construct the dual‐mode nanoprobes.…”

Silica Nanoparticle-Based FRET System for Hydrogen Sulfide Detection in Biological and Food Samples

“…Hydrogen sulfide (H 2 S), a key endogenous gasotransmitter, plays a pivotal role in the realms of biomedical science and food safety. − H 2 S can regulate vascular functions, including vasodilation and blood pressure control, directly impacting cardiovascular health . Its role in mitigating diseases like hypertension, atherosclerosis, and myocardial infarction is underscored by its ability to modulate endothelial cell functions, offering cardioprotective effects. − In the nervous system, H 2 S exhibits neuroprotective properties, such as antioxidation and anti-inflammation, playing a key role in the progression of neurodegenerative diseases like Alzheimer’s and Parkinson’s by influencing neural cell survival and functionality. , In food safety, H 2 S detection is vital for identifying spoilage and potential health hazards, as it is a byproduct of microbial metabolism under anaerobic conditions. − The presence of H 2 S can indicate spoilage and, in some cases, the growth of harmful bacteria like Salmonella , thus serving as a critical marker for food quality and safety. , Therefore, the role of hydrogen sulfide in both biomedical and food safety domains is complex and significant. , Monitoring its levels is crucial for the early diagnosis of diseases and ensuring the quality of food products. − …”