Quantitative determination of deferiprone in human plasma by reverse phase high performance liquid chromatography and its application to pharmacokinetic study

Deferiprone [1, 2 dimethyl-3-hydroxypyrid-4-one] is considered to be the standard iron chelator. Pharmacokinetic studies of generic formulations are required in local condition before placed on the market. High performance liquid chromatographic [HPLC] method was used for quantification of deferiprone in human plasma using UV/VIS detector. Chromatographic separation was carried out on C[18] column, with a mobile phase of methanol-buffer [18:82, v/v], pH 3.5, and caffeine was used as an internal standard. The calibration curve was linear over the range 0.25-10 micro g/mL in human plasma [R[2] = 0.9994]. After oral administration of deferiprone [500 mg] to human, the plasma concentration-time curve of deferiprone was conformed to two-compartment open model. The deferiprone plasma concentration showed a rapid absorption and average area under the plasma concentration-time curve [AUC] of deferiprone was 17.0 +/- 1.23 h. micro g/mL. Average absorption and elimination half-life values of deferiprone of 24 volunteers were 0.62 +/- 0.12 and 2.65 +/- 0.43 hours. This study confirms the rapid absorption of deferiprone in humans. AUC was similar to that previously reported but C[max] was slightly lower than that stated in the literature

Kinetics of diclofenac sodium; single oral dose disposition male volunteers

Objective: The study was conducted to determine the pharmacokinetis of diclofenac in healthy male volunteers so as to establish therapeutic norms. Setting: Department of Chemistry, Physiology and Pharmacology University of Agriculture Faisalabad. Period: During the year 2003

Material and Methods: The concentrations of diclofenac sodium in the plasma of 10 male volunteers were determined by HPLC analysis following oral administration of 50 mg capsules

Results: The diclofenac molecule was found to absorb rapidly and the concentration was detectable even after 10 minutes of the drug intake. The mean+/-SD values for the absorption kinetic parameters were for time to peak concentration [T max] 0.53+/-0.05 hours [range 0.42 to 0.56 hours], C max 2.52+/-0.17 mg/L [range 2.25 to 2.72 mg/L], absorption half-life 0.21+/-0.06 hours [range 0.08 to 0.28 hours] and the absorption rate constant [Ka] 3.77+/-1.75 1/h [range 1.75 to 8.16 1/h]. The disposition kinetics parameters revealed mean+/-SD values for AUC 4.31+/-0.45 h. mg/L and ranged between 3.66 to 5.01 h. mg/L, c Volume of the Central Compartment [V] 9.41+/-2.12 L range 7.08 to 12.79L, Volume of distribution 46.34+/-20.37 liter ranged 32.64 to 79.18L, distribution half-life 0.32 +/- 0.10 hours range 0.19 to 0.47 hours and elimination half-life 2.80 +/- 1.35 hours range 1.61 to 5.58 hours and the mean residence time [MRT] 1.94+/-2.62 hours range 1.86 to 3.87 hours

Conclusions: Variable parameters were observed for disposition kinetics of diclofenac in this pilot study indicating the need for dosage adjustment and its evaluation

Excretion of free and conjugated acetaminophen; assessment in urine of female volunteers

Acetaminophen [Paracetamol] was given orally to 08 normal female volunteers of 20-22 years age and 48-62: kg body weight and the excretion of free/unchanged and conjugated drug was determined in urine by a spectrophotometric method. Normal urine pH ranged from 4.03 to 6.16 and the rate of urine flow was 0.007 to 0.036 ml/min.kg body weight. The mean +/- SD values for the cumulative% age of the dose excreted in 24 hours urine as total drug was 54.1 +/- 15.5, free or unchanged 28.7 +/- 9.10 and the conjugated metabolites were 27.3 +/- 13.7%. The excretion rate of the drug did not show any relationship with the rate of urine flow [diuresis] and pH of the urine. The observed values for the urinary excretion of the drug and metabolites are different than the values recorded in literature