HPLC-MS/MS method for determination of sodium cromoglycate concentration in human plasma and its pharmacokinetics

The study established an HPLC-MS/MS method for determining the concentrations of sodium cromoglycate in human plasma and evaluated the pharmacokinetics of nasal drops and nasal spray. A C₁₈ column was used to separate sodium cromoglycate in plasma with a mobile phase of a mixture of ammonium-methanol (involves 50% acetonitrile) (15∶85) at a flow rate of 0.4 mL·min^-1. Electronic spray ionization (ESI) and multiple-reaction monitoring (MRM) were used for the determination of sodium cromoglycate in human plasma. The linear range of the standard curve of sodium cromoglycate was from 0.3 to 20 ng·mL^-1, and the minimum concentration of detection was 0.3 ng·mL^-1. The extraction recovery was more than 94.1%, intra-day and inter-day RSD were less than 14.3%. After a single dose of sodium cromoglycate, the main pharmacokinetic parameters of nasal spray and nasal drops were as follows, T_1/2 (1.82±0.54) h, (1.59±0.52) h; T_max (0.47±0.12) h, (0.44±0.15) h; C_max (9.79±4.66) ng·mL^-1, (10.88±4.05) ng·mL^-1; AUC_{0-5 h} (11.52±3.46) ng·mL^-1·h, (12.63±4.23) ng·mL^-1·h, F_r (93.6±13.8)%. The method is sensitive, rapid and accurate. It is suitable for therapeutic drug monitoring and human pharmacokinetic study of sodium cromoglycate.