ABSTRACT
Gelucire 50/13 [G50/13] was assessed to develop controlled release formulation of salbutamol sulphate [SBL] a highly water soluble drug by semisolid matrix filling capsule technique. Drug release profiles of SBL release by using G50/13 and its blends with other hydrophilic or hydrophobic materials were investigated. Lipid matrix formulations prepared with increasing amount of polymer showed a substantial decrease in release rate of the drug while increasing drug amount in fixed polymer concentration did not significantly affect the release profile. Polyethylene glycol 6000 caused an increased water uptake resulting in fast erosion of the matrix whereas cetostearyl alcohol and stearic acid caused retardation in drug release. These findings confirm that a considerable amount of Gelucire is required alone or in combination with hydrophobic substances in order to sustain the release profiles of water soluble drugs. More linear profile was obtained by using matrix comprising Gelucire/stearic acid blend in more than 85% that was comparable to standard, Ventolin SR tablet. The test formulation showed a significant decrease at pH 1.0 and the drug release rate increased at high stirring speed. Moreover, short term stability of controlled release test formulation indicated slight increase in dissolution rate at high temperature
ABSTRACT
Ciprofloxacin was given orally to 28 healthy male volunteers for single oral dose of 500 mg; Plasma samples were collected at different time's interval between 0 and 12 h and analyzed both by high pressure liquid chromatography and by a microbiological assay. The detection limits [LOD] were 0.02 ug/ml and 0.1 ug/ml, for both methods respectively. For each method, coefficients of variation [R[2]] were 0.9995 and 0.9918 in plasma and limit of quantitation [LOQ]. 02 and 0.5 ug/ml. The Comparison of means maximum concentration 2.68 ug/ml at 1.5 h for test and 2.43 ug/ml are attain in HPLC method of Reference at 2 hrs respectively. The plasma concentrations measured by microbiological assay of reference tablet are 3.95 microg/ml [mean +/- SE] at 1 hour and 3.80 microg/ml [mean +/- SE] at 1 h. The concentrations in plasma measured by microbiological method were markedly higher than the high-pressure liquid chromatography values which indicates the presence of antimicrobially active metabolites. The mean +/- SE values of pharmacokinetic parameters calculated by HPLC method, for total area under the curve [AUC 0-infinity] were 13.11, and 11.91 h.mg/l for both test and reference tablets respectively. The mean +/- SE values of clearance measured in l/h were 44.91 and 48.42 respectively. The elimination rate constant Kel [l/h] showed 0.17 l/h for test and 0.15 l/h reference tablets and likewise, absorption half-life expressed in hours shown 0.67 h for test and 1.04 h for reference respectively. The Mean Residence Time for test is 5.48 h and 5.49 h for reference. The mean +/- SE values of pharmacokinetic parameters [Microbiological assay] for total area under the curve [AUC 0-infinity] were 22.11 and 19.33 h.mg/l for both test and reference tablets respectively. The mean +/- SE values of clearance measured in l/h were 29.02 and 31.63 respectively. The elimination rate constant Kel [l/h] showed 0.21 l/h for test and 0.20 l/h reference tablets and likewise, absorption half-life expressed in hours shown 0.86 h for test and 0.56 h for reference respectively. The Mean Residence Time for test is 5.27 h and 4.67 h for reference. Significant difference observed between two methods
ABSTRACT
Pharmacokinetics and bioequivalence studies of two ciprofloxacin tablet brands [trial batch of ciprofloxacin [Test] and Reference] were conducted in 14 healthy male volunteers after oral administration. Each brand [test and reference] consisted of 500 mg of ciprofloxacin. The drug was analyzed in plasma samples with a microbiological assay using Streptococcus faecalis as test organism. The elimination half-life of 3.00 +/- 0.21 and 3.28 +/- 0.11 h was calculated for both brands. The peak plasma concentrations of [3.59 +/- 0.26 ug/mL] and [3.34 +/- 1.20 ug/mL] was attained in about 1.48 +/- 0.11 hour and 1.47 +/- 0.05 for both Test and Reference ciprofloxacin respectively. The mean +/- SE values for total area under the curve [AUC O-infinity] were 26.15 +/- 1.35, and 24.95 +/- 0.93 hmg/1 for both test and reference tablets respectively. The mean +/- SE values of clearance were 24.83 +/- 1.63 and 24.73 +/- 1.11 1/h for both formulations respectively. The ratio of elimination rate constant Kel [l/h] was 1.14 percent difference between the test and reference tablets and likewise, half-life [t1/2beta] expressed in hours showed the ratio of 0.91 percent. This study indicated that all the pharmacokinetic and bioequivalence parameters for both ciprofloxacin formulations are statistically non-significant, hence both formulations are bioequivalent
Subject(s)
Humans , Male , Therapeutic EquivalencyABSTRACT
Bioavailabilities of seven tablets of ciprofloxacin were determined. The co-rrelation between in-vivo bioavailability parameters and in-vitro dissolution rates were studied. Ciprofloxacin concentration from the blood was determined by microbiological assay technique. The release pattern of ciprofloxacin from tablets, which were determined by dissolution USP paddle method and spectrophotometric method was used to determine the concentration. All the parameters of ciprofloxacin bioavailability i.e., Tmax, Cmax, AUC and absorption rate constant [Ka] showed no significant correlation with dissolution rates at T30%, T50%, T90% and dissolution at 30 mins with aims as in-vivo bioequvalence waiver. The value of dissolution test used as quality tool for predicting in-vivo performance of drug product is significantly enhanced, if the in-vivo - invitro relationship [correlation or association] is established