A new reverse phase HPLC method with fluorescent detection for the determination of salbutamol sulfate in human plasma

A sensitive reverse phase-high performance liquid chromatography (RP-HPLC) method with fluorescent detector (FLD) was developed and optimized for salbutamol sulfate (SS) determination in human plasma. In this regard, mobile phase specifications, extraction procedures and excitation and emission wavelengths were optimized. The HPLC system consisted of a Lichrosorb RP-C18 analytical column (4.6 × 200 mm, 5 μm) with FLD operated at excitation 228 nm and emission 310 nm. Mobile phase {CH3OH/(NH4)H2PO4 (67 mM) (pH 3.0)/triethylamine (TEA), 50/50/0.02 (v/v/v %)} was run at a flow rate of 0.7 mL/min. To clean up the samples, a liquid-liquid extraction (LLE) procedure was selected and optimized. SS and tramadol hydrochloride (TH) eluted at 4.1 min and 5.2 min, respectively. Adequate extraction efficiency was achieved by DEHP (75.88-85.52 %). The standard curve was linear for the range tested (0.5 80 ng/mL) and the coefficient of determination was 0.9989. A detection limit of 0.17 ng/mL was achieved. The intra- and inter-day precision was less than 4 %. The present assay combines adequate accuracy and precision with sensitivity for SS determination in human plasma and can be applied to study pharmacokinetics of SS sustained release tablets after oral administration in human.