“…Nevertheless, there are few studies that describe determination of fipronil in plasma samples using GC-MS/MS, 17 LC-UV/MS, 18 and GC-MS. 19 Concerning sample preparation, liquid-liquid extraction (LLE) 6,7 and SPE 10,12,[15][16][17][18] are generally used, however solid-phase micro extraction (SPME), 5 gel permeation chromatography (GPC), 8 Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) 14 and matrix solid-phase dispersion (MSPD) 9,11,13,19 have also been used. In analytical methods, the customary procedure is the IS method, where a compound that is not part of the sample (IS) is added at known and constant concentrations to the sample before performing the analysis.…”