A highly chromogenic selective Rhodamine-chloride-based fluorescence probe activated by cysteine and application in living cells and zebrafish

Cysteine (Cys), one of the biological thiols, which plays critical roles in biological system regulating the balance of redox homeostasis. In order to monitor the level of Cys in the living cells and organisms, a chromogenic fluorescence probe Rhocl-Cys based on Rhodamine chloride exhibiting the preferable performance of fluorescence turn-on response reacting with Cys was presented. Rhocl-Cys responded rapidly to Cys within 20 min, and had stable fluorescence intensity within pH 6.0-10.0, high selectivity towards Cys and the anti-inference capability with a low detection limit of 0.80 μM. In particular, Rhocl-Cys could qualitatively and quantitatively monitor the level of endogenous and exogenous Cys in living cells and successfully apply to zebrafish detecting Cys. Therefore, these results might further provide the basis exploring the role of Cys in biological system and facilitate as clinical diagnostic molecular tools.

A novel ratiometric fluorescent and colorimetric sensor based on a 1,8-naphthalimide derivative for nanomolar Cu2+ sensing: smartphone and food applications

A novel 1,8-naphthalimide-based chemical sensor with ratiometric fluorescence behavior, as well as “naked-eye” response was developed for the sensitive and specific determination of Cu2+ at nanomolar levels.

A simple and rapid determination of Al(III) in natural water samples using dispersive liquid-liquid microextraction after complexation with a novel antipyrine-based Schiff base reagent

The purpose of this study is the development of a novel strategy for the determination of Al³⁺ ions using the combination of dispersive liquid-liquid microextraction (DLLME) and UV-Vis spectrophotometry. The method is grounded in the complexation between a novel antipyrine-based Schiff base reagent (EHMP) and Al³⁺ ions. Aluminum concentrations were detected using UV-Vis spectrophotometry at 260 nm and this technique was optimized using the absorbance value of EHMP-Al complex. pH, mixing period, type and volume of organic solvent, etc. were optimized stepwise in order to find out optimum experimental conditions. The limit of detection and the limit of quantification values for the improved analytical method were to be estimated 0.31 and 1.03 μmol.L^-1, respectively. The new strategy was successfully performed to define Al³⁺ ions in natural water samples with RSD values (84.01-107.71%) and recovery values (0.01-0.09%).