Influence of sodium addition on taurine adduct formation generated in acetic acid/acetate salt buffer applied in LC–MS/MS analysis

To investigate the influence of sodium ion addition on analyte adduct formation generated in acetic acid/acetate salt buffer appropriate infusion experiments of a 1 and 10 μg/mL taurine solution prepared both in methanol with a 1 mmol L−1/10 mmol L−1 CH3COONH4/CH3COOH buffer and with a 1 mmol L−1/10 mmol L−1 CH3COONa/CH3COOH buffer were performed. The results achieved revealed that sodium ion concentration has a relevant influence on taurine adduct formation in the negative electrospray ionisation mode since depending on conditions applied different analyte adducts are favored. Sodium ions which originate from the glassware/chemicals make an effective detection of taurine dimer adducts possible, but taurine adducts with sodium acetate are not formed effectively. On the other side sodium ion addition enables an effective taurine adduct formation with sodium acetate, but taurine dimer based adducts can be observed only at higher analyte concentrations.