Determination and Uncertainty Analysis of Imidacloprid Residue in Flue Cured Leaf Matrix of Nicotiana Tabacum L.

Presence of pesticide residues in tobacco (Nicotiana tabacum L.) leaf matrix increases health risk of the consumer, and hence, determination of pesticide residues in tobacco is an issue of serious concern around the world. Present study details the sample preparation and analysis of imidacloprid residues in the Flue Cured Virginia (FCV) tobacco by highperformance liquid chromatography (HPLC) coupled with ultra-violet (UV) detector. The extraction method involves mechanical agitation of tobacco leaf matrix with acetone (1:10) for 45 min at 200 rpm, followed by sequential liquidliquid-partitioning and clean-up with florisil. The method provided 83.7–97.5% recovery with precision relative standard deviation (RSD) less than 10%. Matrix induced signal suppression was recorded at lower level of pesticide spike (mention concentration to specify what do mean by lower level). The method provided acceptable intra-laboratory precision (HorRat ratio mostly < 0.5) and global uncertainty (11.72% at guidance residue level (GRL) of 5 μg g⁻¹ for imidacloprid in tobacco), which complies with the international regulatory specifications. By considering efficiency of method, economics of analysis and analyst's safety, the present method can be adopted by laboratories to monitor imidacloprid residue in FCV tobacco leaf matrix for consumers’ safety.