Enhanced Sulfite-Selective Sensing and Cell Imaging with Fluorescent Nanoreactors Containing a Ratiometric Lipid Peroxidation Sensor

Abstract

The detection of SO 2 and its derivatives is indispensable for monitoring atmospheric, water quality, and biological fluctuation of oxidative stress and metabolism of biothiols within native cellular contexts. In this article, the brush copolymer nanoreactors containing amine-terminated PDMS were used to encapsulate the fluorescent indicator C11-BDP, forming sulfite-sensitive nanoreactors (ssNRs). Surprisingly, the ssNRs were found to be highly selective to sulfite over a range of reactive oxygen/nitrogen/sulfur species and anions, which was not observed with freely dissolved indicators. The ssNRs showed a rapid response (t 95 = 65 s), an excellent detection limit (0.7 μM), and a very high sensitivity (ca. 1000-fold ratiometric intensity change) to sulfite. For cellular studies, the ssNRs exhibited negligible toxicity and could be endocytosed into endosomes and lysosomes. Finally, the ssNRs allowed us to visualize the different responses of three different types of cells (pre-adipocytes, RAW264.7, and HeLa cells) to external stimuli in the culture media with sulfites and lipopolysaccharides.

Computation-Assisted Design of ssDNA Framework Nanorobots for Cancer Logical Recognition, Toehold Disintegration, Visual Dual-Diagnosis, and Synergistic Therapy

“…As indicated by the cell imaging of CEM cells (Figure S6A in the Supporting Information), the Cy5-labeled nanorobots were endocytosed and localized to lysosomes during the early incubation. 26,27 Thereafter, ssDNA nanorobots entered into the cytoplasm, indicated by a decrease in the overlapped signals between red (Cy5-labeled nanorobots) and green (lysosomes) ones. Furthermore, the rigid structure of ssDNA nanorobots facilitated the intracellular delivery, based on a comparison with the one without rigid structures (Figure S6B in the Supporting Information).…”

Background-Free and Reversible Upconversion Hydrogel Sensing Platform for Visual Monitoring of Sulfite

“…At present, various methods such as electrochemistry, titration, chromatography, and flow injection analysis have been used to detect SO 2 and its derivatives. − These analytical techniques always require complex instruments and time-consuming procedures. In contrast, fluorescent detection has unique advantages such as simple operation, high sensitivity, and noninvasive detection. − Therefore, it has broad application prospects in the detection of SO 2 derivatives. − In particular, the immobilization of fluorescent probes on test strips combined with smartphones and cheap three-dimensional (3D) printing technology provides a low-cost and operation-convenient strategy for the detection of SO 2 derivatives. Therefore, the core component of this on-site detection is the fluorescent test strip.…”

Copper 2-Methylimidazole Nanostructure-Based Colorimetric Fabric Sensor for Real-Time Monitoring of Ambient Sulfur Oxides

“…Among the various gas detection techniques, chemiresistive gas sensing is a common method of SO 2 detection with fast response time and high sensitivity. − However, there are obvious disadvantages of this technique in that its sensing capability can be affected by the environmental humidity and it requires an intricate process of analyzing the electrical signals. − To overcome these drawbacks, developing an easy-to-use visual sensor is needed. , Previously, a fluorescence sensor that responds to SO 2 gas has been used in the biological study. ,,, However, the fluorescent response is not easily recognizable by the naked eye under visible light, and this limits the practical application of fluorescence indicators in industrial fields or common public environments. , For the colorimetric detection of SO 2 under visible light, Yang et al developed a sensor in the form of porous core–shell particles by implementing a mixture of zinc chloride, sodium nitroprusside, and hexamine as a chromatic indicator. This sensor material converted the color from pale yellow to red upon reaction with SO 2 gas by the Boedeker reaction, demonstrating detection ability under visible light.…”

“…Deteriorated air quality with harmful gases and particulate matter brings about a rising concern. , In particular, sulfur dioxide (SO 2 ) emission, which mostly emerges from the combustion of fossil fuels, has drawn attention because of its detrimental effect on human health including asthmatic attacks, allergic reactions, cardiovascular disease, bronchitis, laryngitis, and neurological disorders. − SO 2 is easily hydrated in the form of sulfate (SO 4 2– ) and bisulfite (HSO 3 – ) upon exposure to water molecules, and these species can be even more detrimental to human health. − For effective protection from exposure to such hazardous gases, the timely detection of SO 2 and its derivatives is required with appropriate sensitivity and facile usability.…”

“…18,19 Previously, a fluorescence sensor that responds to SO 2 gas has been used in the biological study. 5,9,11,20 However, the fluorescent response is not easily recognizable by the naked eye under visible light, and this limits the practical application of fluorescence indicators in industrial fields or common public environments. 12,21 For the colorimetric detection of SO 2 under visible light, Yang et al 22 developed a sensor in the form of porous core−shell particles by implementing a mixture of zinc chloride, sodium nitroprusside, and hexamine as a chromatic indicator.…”