Simple and Sensitive Multi-components Detection Using Synthetic Nitrogen-doped Carbon Dots Based on Soluble Starch

Cellulose as Source and Matrix for Fluorescent Chemo-Sensors

The review explores the pivotal role of cellulose in enhancing the sensing capabilities of fluorescent chemo-sensors, particularly carbon dots (CDs) and delineates cellulose's multifaceted contributions as both a precursor and stabilizing matrix, highlighting its structural adaptability across varied forms-hydrogels, aerogels, films-to bolster the stability, sensitivity, and selectivity of these sensors. Cellulose's structural versatility enables advanced functionalization, fostering a robust platform that amplifies the stability and functional efficiency of CDs across diverse sensing paradigms. The investigation encompasses utilization of cellulose as precursor for CDs, cellulose nanocrystals and matrix for the integration of CDs, elucidating their collective impact on advancing fluorescence-based detection technologies.

Facile synthesis of N-doped graphene quantum dots as a fluorescent sensor for Cr(vi) and folic acid detection

The development of stable fluorescent sensors for toxic pollutants and drugs is meaningful to the environment and public health. In this work, nitrogen-doped graphene quantum dots (N-GQDs) were facially synthesized by a one-step hydrothermal method using soluble starch and l-arginine as carbon and nitrogen sources in pure water at 190 °C for 4 h. The as-synthesized N-GQDs were well characterized and displayed blue fluorescence emission at 445 nm with excellent pH stability, salt tolerance, thermostability, photobleaching resistance and reproducibility. Moreover, N-GQDs could serve as an "on-off" sensor for selective detection of Cr(vi) and folic acid with low detection limit (0.80 and 2.1 μM), good linear correlation over wide linear range (0-50 μM and 0-200 μM) as well as short response time (<10 s). The practical applications of N-GQDs for Cr(vi) and folic acid detection in actual samples were further investigated and showed acceptable recoveries (92-105%) with relative standard deviations less than 5%. These results indicated that this N-GQDs-based sensor could be a potential alternative for Cr(vi) and folic acid detection in the fields of environmental monitoring and drug analysis.