One-pot facile synthesis of green-emitting fluorescent silicon quantum dots for the highly selective and sensitive detection of nitrite in food samples

Owing to the outstanding properties, fluorescent silicon quantum dots (SiQDs) have attracted immense attention in recent years. In this work, the facile synthesized, environment friendly green-emitting SiQDs (g-SiQDs) were prepared for the detection of nitrite (NO2-) It has excellent merits including excellent water-dispersible, photostability and salt tolerance. The fluorescence peak at 503 nm could be selectively quenched by NO2- due to the synergy of inner filter effect (IFE) and photo induced electron transfer (PET). There was a linear relationship between fluorescence quenching efficiency and the concentration of NO2- from 0.1 to 6.0 mu M (R-2 = 0.9969) with a limit of detection (LOD) of 25 nM, and the sensor displayed a significant selectivity toward NO2-. Furthermore, the g-SiQDs were successfully applied to analysis NO2- in food samples after simple pretreatment with satisfactory recoveries, and our method has good potential for routine analyze of NO2- in food samples.