Interference by metabolites and the corresponding troubleshooting during the LC–MS/MS bioanalysis of G004, a bromine-containing hypoglycemic agent

Bioanalytical chromatographic method validation according to current regulations, with a special focus on the non-well defined parameters limit of quantification, robustness and matrix effect

“…This is a common practice in industry, where effect of co-medication is widely studied according to a survey carried out by EBF [49]. On the other hand, very few scientific papers follow this approach [50][51][52][53]. Ansermot et al studied the selectivity of a method for the quantification of selective serotonin reuptake inhibitors by spiking plasma samples with 63 common medications in the psychiatric population [52].…”

Gradient elution mode for the troubleshooting of matrix effect on the determination of G004 in different tissues by LC‐MS/MS

“…The stream selection valve of MS was set to waste at 3 min until the next injection. The selective procedure of the MS condition of G004 and the IS was reported in our previous study (Hu et al, 2012;Hu et al, 2014).…”

“…It is generally accepted that acidic compounds are readily deprotonated to form anions for the negative ESI in mobile phases with a pH above their pK a (Bonfilio et al, 2010;Yan et al, 2011). In the earlier studies, the poor detection limits of LC-MS/MS for G004 in the negative-ion mode were reported using a near-neutral or typical basic eluent with high concentration of ammonium acetate (Li et al, 2007;Liu et al, 2011;Hu et al, 2012;Hu et al, 2014). Unexpectedly, in this study, the acidic mobile phase without the addition of the ammonium acetate promoted both the chromatographic separation and the peak shape.…”

“…Unlike liquid matrices, bioanalysis in tissues offers unique challenges such as an appropriate tissue sample preparation, owing to the heavier phospholipids-based interferences brought from the extraction process (Xue et al, 2012). So far, a variety of HPLC, LC-MS and LC-MS/MS methods have been reported for the quantitative determination of G004 in pharmaceutical formulations (Hu et al, 2012;Hu et al, 2014) quality criteria and pharmacokinetic research (Li et al, 2007;Hu et al, 2012;Hu et al, 2014). None of them was suitable for the tissue distribution study of G004 in rats.…”

“…None of them was suitable for the tissue distribution study of G004 in rats. The physicochemical properties and the low bioavailability of G004 (Hu et al, 2012;Hu et al, 2014), associated with intense matrix effects and limited sensitivity derived from different tissues, are the major obstacles for G004 tissue distribution study. Thus the aim of the present work was to develop and validate an improved method for the analysis of G004 and to verify its suitability among different tissue samples.…”