ABSTRACT
The aim of the study presented is to formulate and evaluate Acarbose controlled release matrix tablets by means of different grades of polymer Ethocel and different co-excipients with the intention to see their effects on drug release profile during in vitro dissolution studies. Controlled release dosage forms is gaining rapid popularity due to its positive aspect of reduction in dosage frequency and curtailing side effects. Controlled released tablets of Acarbose were prepared by direct compression method, using Ethocel[registered sign] Standard 7 Premium and Ethocel[registered sign] Standard 7 FP premium polymer. The effect of co-excipients including hydroxypropyl methylcellulose [HPMC], Carboxymethyl cellulose [CMC] and starch on the drug placing 30% lactose were also examined. In-vitro studies were carried out with the help of phosphate buffer [PH 7.4] as dissolution medium. Drug release mechanism was assessed by applying various kinetic models. Similarly / dissimilarity factor f[2]/ f[1] were applied for determination of dissolution profile of the test and reference formulations. Physiochemical characteristics were in the USP satisfactory limits. Conventional Acarbose tablet released 97% of the drug within 2 hrs. Ethocel[registered sign] Standard 7 premium and Ethocel[registered sign] standard 7 FP released 59.9% and 47.01% of the drug within 6 and 99.9% and 97% within 24 hours, respectively. This effect possibly has been aceived owing to the smaller particle size of the Ethocel[registered sign] Standard 7 FP premium which show evidence of anomalous, nonfickian release kinetics. Co-excipients like HPMC, CMC and starch augment the drug release rates from the matrices which may be attributed to their hydrophilic nature. Ethocel[registered sign] Standard 7 Premium and Ethocel[registered sign] Standard premium 7 FP polymers show a promising response in fruitful production of controlled release tablets by direct compression method
ABSTRACT
The aim of the present study was the formulation and evaluation of controlled release polymeric tablets of Diclofenac Potassium by wet granulation method for the release rate, release pattern and the mechanism involved in drug release. Formulations having three grades of polymer Ethocel [7P; 7FP, 10P, 10FP, 100P, 100FP] in several drugs to polymer ratios [10:3 and 10:1] were compressed into tablets using wet granulation method. Co-excipients were added to some selected formulations to investigate their enhancement effect on in vitro drug release patterns. In vitro drug release studies were performed using USP Method-1 [Rotating Basket method] and Phosphate buffer [pH 7.4] was used as a dissolution medium. The similarities and dissimilarities of release profiles of test formulations with reference standard were checked using f2 similarity factor and f1 dissimilarity factor. Mathematical/Kinetic models were employed to determine the release mechanism and drug release kinetics
ABSTRACT
Lithium remains a mainstay in the acute and prophylactic treatment of bipolar affective disorder. It is used in the augmentation of antidepressant treatment and, less frequently, in the augmentation of antipsychotic treatment of schizophrenia. It is reported to have specific anti-suicidal effects. Thus the effect of Lithium was interesting to study on the glutathione [GSH] level in vivo conditions. Ellman's method has been used to see the effect of lithium on glutathione [GSH] level in whole blood. The time dependent effect of Lithium on the chemical status of glutathione [GSH] was determined in the whole blood [Plasma and cytosolic fraction] of human. The concentration of Glutathione was drastically decreased. The decrease in the glutathione level was concentration and time of interaction dependent, probably due to oxidation of glutathione [GSH] to corresponding disulphide [GSSG]. In this paper the effect of Lithium on the Thiol/GSH level was discussed in vitro, which in principal may present a model of in vivo reaction