Abstract :
In the present work, a rapid and sensitive method for simultaneous determination of penicillin G (PG), benzathine (BE) and procaine (PR) in drug and serum media is introduced. The polar hydro-organic (55/45) mobile phases containing an aqueous solution adjusted to pH = 3.7 and an organic solvent (MeOH) including triethylamine (TEA) and trifluroacetic acid (TFA) are used. The flow rate of 1 ml min-1, a C8 column (150 mm * 46 mm) with 5 (mu)m i.d. and wavelength at 215 nm are selected for optimal separation condition. The limit of detection (LOD), linear concentration range and relative standard deviation (R.S.D.) of this method for the PG are 1.1 (mu)g ml-1, 10-2400 (mu)g ml-1 and 1.7% and for the BE are 1.2 (mu)g ml-1, 12-2100 (mu)g ml-1 and 1.8% and for the PR are 1.5 (mu)g ml-1, 20-2000 (mu)g ml-1 and 2%, respectively. The factorial design is used for the determination of main and interaction effects of pH, flow rate and concentration of MeOH, TEA and TFA in the separation at two levels. Also, the analysis of variance (ANOVA) table is obtained. The results show that TFA and TEA have higher effect than concentration of MeOH, pH and flow rate factors.
