A Novel “Off-On” Fluorescent Probe Based on Carbon Nitride Nanoribbons for the Detection of Citrate Anion and Live Cell Imaging

Abstract

A novel fluorescent “off-on” probe based on carbon nitride (C3N4) nanoribbons was developed for citrate anion (C6H5O73−) detection. The fluorescence of C3N4 nanoribbons can be quenched by Cu2+ and then recovered by the addition of C6H5O73−, because the chelation between C6H5O73− and Cu2+ blocks the electron transfer between Cu2+ and C3N4 nanoribbons. The turn-on fluorescent sensor using this fluorescent “off-on” probe can detect C6H5O73− rapidly and selectively, showing a wide detection linear range (1~400 μM) and a low detection limit (0.78 μM) in aqueous solutions. Importantly, this C3N4 nanoribbon-based “off-on” probe exhibits good biocompatibility and can be used as fluorescent visualizer for exogenous C6H5O73− in HeLa cells.

Illuminating the cells: transient transformation of citrus to study gene functions and organelle activities related to fruit quality

“…In summary, we studied citrus fruit cells at the subcellular level by using a series of fluorescent organelle markers and pH reporters. Different sensors (e.g., roGFP for redox potential 26 ) could also be applied to study the communication between distinct intracellular compartments and specific metabolite (e.g., citrate 27 ) accumulation at the organelle level in fruit cells. Future studies using this method could potentially be useful to reveal the function and regulatory mechanisms of a particular organelle during fruit development or postharvest.…”

Exonuclease III-Regulated Target Cyclic Amplification-Based Single Nucleotide Polymorphism Detection Using Ultrathin Ternary Chalcogenide Nanosheets

“…The calibration equation was Y = 57.46 + 13.97 lg X (R 2 = 0.9952), where Y stands for the fluorescence intensity and X is the concentration of MT. According to the 3σ rule, the limit of detection was calculated to be 250 fM (Hu et al, 2018). The comparison of Ta 2 NiS 5 nanosheet-based biosensor with the conventional reported SNP biosensor based on Ti 3 C 2 nanosheet, GO nanosheet, MoS 2 @Au NPs, and Au NPs is presented in Table S2; the Ta 2 NiS 5 nanosheet-based exhibits high sensitivity for SNP detection.…”