A selective cascade reaction-based probe for colorimetric and ratiometric fluorescence detection of benzoyl peroxide in food and living cells

A novel colorimetric and ratiometric fluorescent probe (Cou-BPO) was readily prepared for specific detection of harmful benzoyl peroxide (BPO). The probe Cou-BPO reacted with BPO via a selective oxidation cleavage-induced cascade reaction of the pinacol phenylboronate group, which resulted in an observable colorimetric and ratiometric fluorescence response towards BPO with a fast response time (<15 min) and a low detection limit (56 nM). For practical application, facile, portable and sensitive test paper of Cou-BPO has been prepared for visual detection of BPO. Furthermore, we employed Cou-BPO as a probe to determine BPO in food samples and living cells.

Highly Sensitive Detection of Benzoyl Peroxide Based on Organoboron Fluorescent Conjugated Polymers

The method capable of rapid and sensitive detection of benzoyl peroxide (BPO) is necessary and receiving increasing attention. In consideration of the vast signal amplification of fluorescent conjugated polymers (FCPs) for high sensitivity detection and the potential applications of boron-containing materials in the emerging sensing fields, the organoboron FCPs, poly (3-aminophenyl boronic acid) (PABA) is directly synthesized via free-radical polymerization reaction by using the commercially available 3-aminophenyl boronic acid (ABA) as the functional monomer and ammonium persulfate as the initiator. PABA is employed as a fluorescence sensor for sensing of trace BPO based on the formation of charge-transfer complexes between PABA and BPO. The fluorescence emission intensity of PABA demonstrates a negative correlation with the concentration of BPO. And a linear range of 8.26 × 10⁻⁹ M–8.26 × 10^–4 M and a limit of detection of 1.06 × 10^–9 M as well as a good recovery (86.25%–111.38%) of BPO in spiked real samples (wheat flour and antimicrobial agent) are obtained. The proposed sensor provides a promising prospective candidate for the rapid detection and surveillance of BPO.

Biocompatible Ionic Liquid Based on Curcumin as Fluorescence Probe for Detecting Benzoyl Peroxide without the Interference of H2O2

Accurate estimation of the level of benzoyl peroxide (BPO) is of considerable significance because of its threat to humanity and environment. Several research efforts have been devoted to the detection of BPO by fluorescent method with high sensitivity and selectivity. However, it remains challenging to eliminate the interference of H₂O₂ due to its similar properties to BPO. In this work, the first demonstration of fluorescent and colorimetric probe for specific detection of BPO without the disturbance of H₂O₂ was achieved by curcumin-based ionic liquid (CIL) that possesses simple fabrication, good biocompatibility, and low cost. The fluorescence quenches and emission peak blue-shifts once the probe selectively interacts with BPO, whereas the other possible interfering agents, including H₂O₂, do not have this phenomenon. The probe CIL exhibits prominent sensitivity for BPO sensing and enables the detection limit at levels as ultralow as 10 nM. The local detection of BPO in practical samples is realized by visualization using a portable device derived from CIL-based liquid atomizer.

A selective cascade reaction-based probe for colorimetric and ratiometric fluorescence detection of benzoyl peroxide in food and living cells

A colorimetric and ratiometric fluorescent probe (Cou-BPO) was prepared for food analysis and cell imaging; it showed high selectivity, sensitivity, visible and fast response towards BPO via a selective oxidation cleavage-induced cascade reaction.

A selective cascade reaction-based probe for colorimetric and ratiometric fluorescence detection of benzoyl peroxide in food and living cells

A colorimetric and ratiometric fluorescent probe (Cou-BPO) was prepared for food analysis and cell imaging; it showed high selectivity, sensitivity, visible and fast response towards BPO via a selective oxidation cleavage-induced cascade reaction.

Benzothiazole integrated into a cryptand for ESIPT-based selective chemosensor for Zn2+ ions

A novel 2(2′-hydroxyphenyl) benzothiazole-based cryptand (L) exhibits high fluorescence intensity in the presence of Zn²⁺ ions by stopping the excited state intramolecular proton transfer (ESIPT) process with a detection limit of 0.20 μM.

A new water-soluble two-photon fluorescent probe for detection of trace benzoyl peroxide in wheat flour and in living cell and tissue imaging

Benzoyl peroxide (BPO), a member of small-molecule reactive oxygen species (ROS), has attracted considerable attention because of its impact on human health and industrial importance.

Rapid and Visual Detection of Benzoyl Peroxide in Food by a Colorimetric and Ratiometric Fluorescent Probe

A coumarin-based fluorescent probe was prepared for rapid and visual detection of benzoyl peroxide. The probe could quantitatively determine benzoyl peroxide with fast response (<6 min), high sensitivity, and low limit of detection (163 nM). The probe exhibited good response toward benzoyl peroxide with a significant color change from blue to yellow along with fluorescence color alteration from red to blue. The probe determined benzoyl peroxide in real food samples (wheat flour, noodle, and dumpling flour) with good recoveries (90-114%). Furthermore, the probe was prepared into a paper-based test kit to determine benzoyl peroxide (30-100 μM) in real food samples with noticeable color and fluorescence change.

A benzothiazole-based fluorescent probe for hypochlorous acid detection and imaging in living cells

A benzothiazole-based turn-on fluorescent probe with a large Stokes shift (190nm) has been developed for hypochlorous acid detection. The probe displays prompt fluorescence response for HClO with excellent selectivity over other reactive oxygen species as well as a low detection limit of 0.08μM. The sensing mechanism involves the HClO-induced specific oxidation of oxime moiety of the probe to nitrile oxide, which was confirmed by HPLC-MS technique. Furthermore, imaging studies demonstrated that the probe is cell permeable and can be applied to detect HClO in living cells.

Benzoyl Peroxide Detection in Real Samples and Zebrafish Imaging by a Designed Near-Infrared Fluorescent Probe

A novel near-infrared fluorescence off-on probe, (E)-3,3-dimethyl-1-propyl-2-(2-(6-(2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyloxy)-2,3-dihydro-1H-xanthen-4-yl)vinyl)-3H-indolium (1), is developed and applied to benzoyl peroxide (BPO) detection in real samples and fluorescence imaging in living cells and zebrafish. When arylboronate as the recognition unit is connected to a stable hemicyanine skeleton, the probe is readily prepared, which exhibits superior analytical performance, such as near-infrared fluorescence emission over 700 nm and high sensitivity with a low detection limit of 47 nM. Upon reaction with BPO, phenylboronic acid pinacol ester is oxidized, followed by hydrolysis and 1,4-elimination of o-quinone methide to release fluorophore. In addtion, the probe displays high selectivity toward BPO over other common substances, which makes it of great potential use in quantitative and simple detection of BPO in wheat flour and antimicrobial agent. More importantly, the probe has been successfully demonstrated for monitoring BPO in living HeLa cells and zebrafish. The probe with superior properties could be of great potential use in other biosystems and in vivo studies.

Carbazole- and/or triphenylamine-based D–π–D multiarylamino dyes: synthesis, characterization and photophysical properties

One-photon and two-photon fluorescence quenching by benzoyl peroxide of D–π–D multiarylamino dyes was investigated.

Bright and photostable fluorescent probe with aggregation-induced emission characteristics for specific lysosome imaging and tracking

We develop a new lysosome-targeting AIE fluorescent probe tetraphenylethene-morpholine (TPE-MPL), by incorporating a typical lysosome-targeting moiety of morpholine into a stable tetraphenylethene skeleton. Due to both the AIE and antenna effects, TPE-MPL possesses superior photostability, appreciable tolerance to microenvironment change and high lysosome targeting ability. Our findings confirm that TPE-MPL is a well-suited imaging agent for targeting lysosome and tracking dynamic movement of lysosome. Moreover, due to its synthetic accessibility, TPE-MPL could be further modified as a dual-functional probe for lysosome, thereby gain further insight into the role of lysosome in biomedical applications.

A 2-(2'-hydroxyphenyl)benzothiazole (HBT)-quinoline conjugate: a highly specific fluorescent probe for Hg(2+) based on ESIPT and its application in bioimaging

A benzothiazole derived chemosensor L has been designed based on the excited-state intramolecular proton transfer (ESIPT) mechanism to afford a fluorescence turn-on response specifically in the presence of Hg(2+) ions over a host of biologically relevant metal ions as well as toxic heavy metal ions. The chemosensor exhibits high sensitivity with the detection limit down to 0.11 μM. The metal binding is supported by (1)H NMR titrations, ESI-MS spectral analysis and substantiated by theoretical calculations using the density functional theory. The probe shows cell membrane permeability and efficiency for the detection of Hg(2+) in HeLa cells.

Visualization of endogenous and exogenous hydrogen peroxide using a lysosome-targetable fluorescent probe

Reactive oxygen species (ROS) play crucial roles in diverse physiological processes; therefore, the efficient detection of ROS is very crucial. In this study, we report a boronate-based hydrogen peroxide (H2O2) probe having naphthalimide fluorophore. This probe also contained a morpholine moiety as a directing group for lysosome. The recognition property indicated that the probe exhibited high selectivity towards H2O2 not only in the solution but also in the living cells. Furthermore, it was used to monitor the level of endogenous and exogenous H2O2. These results support that the probe can function as an efficient indicator to detect H2O2.

A highly sensitive and selective assay of doxycycline by dualwavelength overlapping resonance Rayleigh scattering

A dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS) method was developed and validated for highly sensitive and selective assay of doxycycline residues in several meat samples. The response signals were dependent on the specific multi-site coordination between lanthanum(III) and doxycycline (DOTC). And La(III)-DOTC complex would further aggregate to form [La(III)-DOTC]n nanoparticles, resulting in the occurrence of two new scattering peaks. Notably, with the addition of DOTC, the increments of both of these two wavelengths were proportional to the concentration of DOTC over the ranges of 3.9-4.0×10(3) nmol L(-1) (1.7-1.8×10(3) μg/kg). The detection limit of DWO-RRS was 1.1 nmol L(-1) (0.5 μg/kg), which was lower than or comparable to most of the published methods. Additionally, the generating mechanisms of multi-response RRS signals were discussed and a semi-empirical principle was established for better design of multi-response RRS probes.

Cascade reaction-based rapid and ratiometric detection of H2S/S2− in the presence of bio-thiols with live cell imaging: demasking of ESIPT approach

For the rapid, ratiometric, fluorogenic and “naked eye” detection of H₂S/S²⁻, a pro-excited state intramolecular proton transfer (ESIPT)-based receptor, 2-formyl-benzoic acid 2-benzothiazol-2-yl-phenyl ester (FBBP), has been designed.

FRET based ‘red-switch’ for Al3+ over ESIPT based ‘green-switch’ for Zn2+: dual channel detection with live-cell imaging on a dyad platform

Our designed chemosensor, rhodamine-HBT-dyad (RHD), selectively detects two biologically important ions (Al³⁺ and Zn²⁺) at two different wavelengths (red and green, respectively) through FRET and ESIPT in vitro and in vivo.