Highly selective fluorometric detection of para-nitrophenol from its isomers by nitrogen-doped graphene quantum dots

Fabrication of nitrogen-enriched carbon dots with green fluorescence for enzyme-free detection of uric acid

“…The value of F/F 0 versus the amount of UA shows a good linearity from 0 to 30 mM, and the limit of detection (LOD) was estimated to be 0.22 mM (3S b /k). 13 The linear detection ranges and LOD obtained in the established sensor to detect UA were compared with those in the previously reported studies so as to reveal its performance (Table S2, ESI †). At present, most of the fluorescence detection methods of UA are still based on the indirect detection way in the presence of enzymes, [39][40][41] in contrast, this work realizes the enzyme-free detection.…”

“…To understand the mechanism regarding the FL quenching of NCDs by UA, the Stern-Volmer relationship of UA concentrations versus FL intensities of NCDs was studied. A good linear relationship of the Stern-Volmer equation can indicate that the quenching usually originated from dynamic or static quenching, 13 where the form of the equation is shown in the ESI. † As expected, the Stern-Volmer plot over the UA concentration range of 0-30 mM is obtained with a good linearity relationship (Fig.…”

“…Functional carbon dots (CDs) with excellent fluorescence (FL) properties, low costs, ultralow toxicity, and environmentally friendly characteristics have attracted increasing attention in various fields since the discovery of FL carbon nanoparticles, 12,13 especially in light-emitting devices, photocatalysis and FL sensing. 14 Up to now, two routes have been applied to prepare CDs including the top-down and bottom-up routes.…”

“…The bottom-up route can regulate the sizes, shapes, fluorescence, and chemical structures of CDs with special properties through the rational selection of precursors in addition to the introduction of heteroatoms. [13][14][15] These characteristics are conducive for expanding the application field of CDs, particularly in the development of fluorescent sensors for specific recognition. Gong et al have developed phosphorus and nitrogen dual-doped CDs with bright green FL by mixing glucose, ethylenediamine and concentrated phosphoric acid towards a sensor for the indirect detection of ascorbic acid.…”

Pre-Anodized Graphite Pencil Electrode Coated with a Poly(Thionine) Film for Simultaneous Sensing of 3-Nitrophenol and 4-Nitrophenol in Environmental Water Samples

“…Different analytical methods such as spectrometry [ 18 , 19 ], high-performance liquid chromatography with different detectors [ 20 , 21 ], capillary electrophoresis [ 22 ], flow injection detection [ 23 ], fluorescence [ 24 , 25 ], surface-enhanced Raman spectroscopy (SERS) [ 26 ], and chemiluminescence [ 27 , 28 ] have been used to quantify these nitrophenol isomers. However, common analysis procedures take a long time and are highly expensive, requiring sophisticated instrumentation facility with samples that were pre-treated [ 29 ].…”