ABSTRACT
@#2,6-dimethylbenzenamine was determined as a genotoxic impurity in lidocaine hydrochloride injection, and 2-chloro-N-(2,6- dimethylphenyl) acetamide was determined as potential genotoxic impurity. An LC-MS/MS method was established to research the profiling of genotoxic impurities in active pharmaceutical ingredients (API), homemade preparation and reference preparation on column Agilent ZORBAX Eclipse Plus C18(4.6 mm250 mm，5 μm). The results show that in the homemade preparation the 2,6-dimethylbenzenamine and the 2-chloro-N-(2,6-dimethylphenyl) acetamide may be degraded under oxidation condition and alkaline condition in addition to the introduction from API preparation process. This study provides guidance for genotoxic risk assessment and prescription process optimization of lidocaine hydrochloride.
ABSTRACT
We developed a rapid method to detect Cu2+and glutathione(GSH)based on the fluorescence quenching-recovery properties of graphene quantum dots(GQDs),which were synthesized by the gentle oxidation of graphite powder.The results revealed that the fluorescence intensity of GQDs versus concentration of Cu2+and GSH had good linearity, with the detection limits of 0.01 and 0.1 mmol/L, respectively.The fluorescence quenching was linearly proportional to the concentrations of Cu2+ranging from 1.0 to 10.0 mmol/L;the fluores-cence intensity was linearly enhanced with the concentrations of GSH ranging from 0.1 to 1.0 mmol/L.In addi-tion,the method was successfully applied to the determination of real samples with recoveries falling between 93％-101％ and 96％-107％,respectively.This method is simple,accurate and precise.There was no interference with other familiar co-existing metal ions and potential materials.