Jul 2026· Ecotoxicology and Environmental Safety· Vol 322, pp.
120512
· 0 citations· 39 references
Medicine
TL;DR
Experimental data indicate that probe CDP can effectively detect N2H4 across a broad pH range (5-12) and demonstrates significant potential for imaging N2H4 in living cells and mice models.
Abstract
As a key chemical raw material, hydrazine hydrate (N2H4) is widely used in chemical manufacturing, aerospace propulsion and pharmaceuticals synthesis. However, excessive N2H4 causes serious harms to the environment and organisms. Herein, a ratiometric fluorescence probe CDP has been designed and synthesized from p-hydroxycinnamic acid. Upon interaction with N2H4, the major fluorescence emission peak at 570 nm is blue-shifted to 455 nm, accompanied by a fluorescence color change from pale orange to blue. The detection limit of CDP for N2H4 is determined as 17.08 nM. Experimental data further indicate that probe CDP can effectively detect N2H4 across a broad pH range (5-12). More notably, probe CDP demonstrates significant potential for imaging N2H4 in living cells and mice models. Moreover, probe CDP can be employed for the detection of N2H4 in soil samples and water samples. This work describes a versatile fluorescence probe for detecting N2H4, underscoring its considerable potential in environmental analysis and public health monitoring.
Bisulfite (HSO3−) is widely used as a preservative and antioxidant in the food industry and chemical manufacturing, yet its excessive residues pose risks to food quality, environmental safety, and human health. To achieve rapid, selective, and quantitative detection of HSO3−, a ratiometric fluorescent probe based on a benzothiazole–carbazole unit and a benzoindole ion was developed. Upon reaction with HSO3−, the probe exhibits a distinct dual-emission response, fluorescence intensity decreases at 612 nm and increases at 467 nm, enabling robust ratiometric sensing (F467/F612). Owing to its pronounced fluorescence modulation (emission signal change > 145 nm) and high sensitivity (limit of detection = 0.62 μM), the probe demonstrates reliable performance in aqueous samples and has been successfully integrated into portable test strips and swabs. Furthermore, when coupled with a smartphone-based colorimetric application software, the probe allows convenient and real-time quantification of both gaseous SO2 and aqueous HSO3− across environmental and food-related matrices. This work thus delivers a practical, instrument-free platform for sulfite monitoring in complex real-world settings.
Chunling Zhou, Yanxin Zhang, Ying Sun et al.· Methods and Applications in...· 0 citations
Bisulfite (HSO3-), which exists in equilibrium with sulfite and sulfur dioxide derivatives, plays significant roles in food preservation and biological systems. However, elevated levels of bisulfite are associated with various physiological disorders. Therefore, the development of reliable methods for monitoring bisulfite is of considerable importance. Herein, we report a flavonol-based fluorescent probe, 4-(3-hydroxy-4-oxo-4H-chromen-2-yl) benzaldehyde (BSP), synthesized via a simple two-step reaction using 1-(2-hydroxyphenyl)ethan-1-one and 4-(diethoxy methyl)benzaldehyde. BSP exhibits excellent water solubility and a strong turn-on fluorescence response toward HSO3- in PBS buffer (pH 5.0), with green emission at 515 nm and a large Stokes shift of 155 nm. The probe shows high selectivity and sensitivity with a detection limit of 0.19 µM. The sensing mechanism is attributed to nucleophilic addition of HSO3- to the aldehyde group, suppressing the n → π* transition and enhancing intramolecular charge transfer (ICT), resulting in significant fluorescence enhancement. BSP was successfully applied for bisulfite detection in onion epidermal cells and environmental water samples.
U. Samanta, Anindita Roy, Subhajit Ghosh et al.· Analytical Methods· 0 citations
The sensitive and selective detection of fluoride ions (F-) is of great significance in both environmental and biological systems. A novel near-infrared ratiometric fluorescent probe, PC-SZ-TBS, was designed and synthesized by rationally linking dicyanoisophorone with 2-(2-hydroxyphenyl)benzothiazole. The probe operates via F--triggered cleavage of the silicon-oxygen bond, resulting in a distinct fluorescence color change from yellow to bright red, along with significant fluorescence enhancement at 700 nm. Spectroscopic studies revealed that PC-SZ-TBS exhibits a low detection limit of 2.22 × 10-6 mol L-1 toward F-, maintains excellent stability over a pH range of 4-10, and displays high selectivity with minimal interference from competing species. Biocompatibility assays demonstrated that PC-SZ-TBS possesses low cytotoxicity and robust cell permeability in 4T1 cells, as well as favorable imaging capabilities in living organisms including zebrafish and Arabidopsis thaliana, enabling effective visualization of F- in biological tissues. Furthermore, PC-SZ-TBS was successfully applied to determine F- in real samples such as tap water, lake water, Chinese baijiu, and various fruits. Integrated with a smartphone-based RGB analysis platform, a strong linear correlation between the R/G ratio and F- concentration (R2 = 0.9978) was established, allowing for real-time, portable semi-quantitative detection of F-. This work provides a reliable and versatile tool for the visual monitoring of fluoride ions in both environmental and biological contexts.
Qi Zhou, Wen-Hao Hu, Ke Xiao et al.· Analytical Methods· 0 citations
Sulfites are widely used as preservatives and antioxidants in food, but excessive intake poses health risks. Therefore, rapid, sensitive, and on‑site detection of sulfites is essential for food safety. In this work, a cationic small‑molecule fluorescent probe was synthesized via the condensation of
N
‑ethylcarbazole (electron donor) and a benzoindolium ion (electron acceptor). It exhibits a D–π–A architecture with an intramolecular charge transfer (ICT) effect, showing red fluorescence at 617 nm. Upon reaction with HSO
3
−
through Michael addition at the conjugated C═C bond, the ICT pathway is blocked, leading to fluorescence quenching. The probe displays excellent selectivity for HSO
3
−
(limit of detection = 0.1 µM). Significantly, it can be simply deposited onto filter paper to fabricate easy‐to‐use test strips. Under a 365 nm UV lamp, the test strips exhibit a visible color change from red to blue with increasing HSO
3
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concentration, allowing naked‑eye detection. Coupled with a smartphone color‑reading application, a linear relationship between the blue‐to‐red intensity ratio (B/R) and HSO
3
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concentration enables rapid on‑site quantitative analysis. The test strips were successfully applied to detect residual HSO
3
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in various dried fruit samples. This work provides a simple, low‑cost, and practical method for detecting sulfite levels in food and environmental samples.
Kanli Wang, Chenle Liao, Qian Cao et al.· ChemistrySelect· 0 citations
Thiophenol (PhSH) is a highly toxic aromatic thiol endangering ecosystems, food safety, and human health. Traditional detection methods are limited by instrument dependence and inability for real-time imaging. This study developed a red-emitting fluorescent probe, TTCP-DN, based on the PET mechanism. The probe employs 5-(4-diphenylamino)benzothiophene as the fluorophore and 2,4-dinitrophenoxy as the PhSH-specific recognition moiety, achieving mitochondrial targeting via a pyridine salt. Without PhSH, fluorescence is quenched; upon PhSH-induced reaction, fluorescence restores at 623 nm. The probe has low detection limit (37.8 nM), large Stokes shift (153 nm), good biocompatibility, and high selectivity. It was applied for mitochondrial imaging in 4 T1 cells, qualitative detection and semi-quantitative concentration trend analysis of PhSH in zebrafish, plant tissues, environmental, food and biological samples (recoveries 95-105%), and fabricated into portable paper-based test strips. This work provides a versatile PhSH detection tool and a paradigm for targeted probes of toxic aromatic pollutants.
Yukun Zhang, Xiaoli Li, Ruiyuan Liu et al.· Food Chemistry· 0 citations
Cysteine (Cys) plays an essential role in both food processing and physiological functions; however, excessive intake may pose potential health risks. In this work, a novel ratiometric fluorescent probe DCI‐NI‐Cys, based on naphthalimide‐dicyanoisophorone hybrid, was synthesized for detecting Cys. In the design of the probe, the acrylate group was used as the reaction site for Cys. The probe demonstrated remarkable selectivity and high sensitivity toward Cys detection. Specifically, the limit of detection was determined to be 93 nM in fluorescence spectra and 118 nM in UV–vis absorption spectra, respectively. Moreover, a smartphone‐based sensing platform was successfully developed by coupling the probe with RGB color analysis software. DCI‐NI‐Cys proved capable of detecting Cys in food samples such as cabbage, pear, garlic, and celery with satisfactory recoveries, underscoring its potential for real‐world applications. Impressively, DCI‐NI‐Cys is applicable to image Cys in HepG2 cells and zebrafish.