Abstract:

The blood and cerebrospinal fluid concentrations of levofloxacin in patients undergoing neurosurgical operations were determined by RP-HPLC and its pharmacokinetics was studied. C18H37 column was eluted with the mobile phase of mmol·L^-1 KH2PO4-10 mmol·L^-1(C4H9)4NBr-CH3CN (45:45: 10 v/v, pH 3.0) and the ultraviolet absorbance was monitored at 295nm. Ciprofloxacin was used as internal standard. The mean extractionrecoveries were 74.76% in plasma and 82.43% in CSF, with the lowest detectable limits of 10 μg·L^-1 and 6 μg·L^-1 respectively. The intra-day and inter-day RSD were less than 5%. A single oral dose of 300 mg·LVFX tablets was taken by 10 patients undergoing neurosurgical operations. The pharmacokinetic parameters in plasma and in CSF could be described by one compartment open model. The pharmacokinetic parameters were: plasma Ke 0.125±0.042 h^-1, T1/2 6.054±1.680 h, Tpeak l.049±0.288 h, Cmax 3.670±0.416 mg.L^-1, AUC 33.427±7.316 mg·h·L^-1, Cls 9.463±2.531 L·h^-1, Vd 77.486±7.393 L, CSF Ke 0.109±0.041 h^-1, T1/2 6.946±1.883 h, Tpeak 3.555±1.235 h, Cmax 1.682±0.249 mg·L^-1, AUC 23.697±5.615 mg·h·L^-1, Cls 13.702±5.110 L·h^-1, Vd 126.606±13.198 L.

Key words: RP-HPLC, RP-HPLC, Levofloxacin, Levofloxacin, Plasma, Cerebrospinal fluid, Pharmacokinetics, Plasma, Cerebrospinal fluid, Pharmacokinetics