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Commercially available four national and four international brands of esomeprazole magnesium sustained release matrix tablets were studied in simulated gastric medium (pH 1.2) for 2 hours and simulated intestinal medium (pH 6.8) for 8 hours time period using USP reference dissolution apparatus. All the national and international brands complied with the USP in-vitro dissolution specifications for drug release in simulated gastric medium. However, one of the national brands (Code: MP-1) and one of the international brands (MP-7) failed to fulfill the official requirement of 80% drug release within 8th hour in simulated intestinal medium. Drug release of that national and international brand were 70.49% and 67.05% respectively within the specified time period, however one national brand (Code: MP-4) released 103.46 % drug within 8th hour in intestinal medium. Drug release profiles were analyzed for zero order, first order and Higuchi equation to reveal the release kinetics perspective of esomeprazole magnesium sustained release matrix tablets. It was found that zero order release kinetics was the predominant release mechanism than first order and Higuchi release kinetics for those brands (Code: MP-2, MP-3, MP-4, MP-5, MP-6 and MP-8) which complied with the USP in vitro dissolution specification for drug releases. On the other hand, first order release kinetics was predominant for one national and also one international non compliant brands (Code: MP-1 and MP-6). Key Words: In vitro dissolution; Sustained release; Market preparations; Kinetic analysis; Esomeprazole; National brand; International brand. DOI: 10.3329/sjps.v2i1.5812Stamford Journal of Pharmaceutical Sciences Vol.2(1) 2009: 27-31

Aceclofenac loaded agarose beads were prepared by ionotropic gelation method and drug release profile, swelling index (SI %) and entrapping efficiency (EE %) of aceclofenac were investigated. The drug was dissolved in melted 4 % agar solution in different ratios. Beads were prepared by dropping the hot aqueous solution into a beaker of different percentages of chilled CaCl2 solution followed by filtering the solution and drying at room temperature. The entrapment efficiency was 100±5 %. The swelling index was found to be highest (18.22 % in 4 hours) for beads containing aceclofenac-agar (1:2) in 4 % electrolyte solutions and the swelling property was decreased with increasing electrolyte concentration. In vitro dissolution of beads was carried out in USP apparatus-II (paddle method) at 75 rpm. The drug release was measured by using UV-Spectrophotometer at λmax of 268 nm for acid media and 274 nm for buffer media. The dissolution data were treated with zero order, first order and Higuchi model. Half of the formulations were fitted to Higuchi model and rest half to first order model. Finally it can be concluded that with the increasing polymer (agar) concentration, the release rate of aceclofenac was decreased and swelling index was increased and with the increasing electrolyte concentration, the release rate was increased and swelling index was decreased. Key Words: Aceclofenac, Agarose bead, Electrolyte, Ionotropic Gelation method.  doi:10.3329/sjps.v1i1.1780 S. J. Pharm. Sci. 1(1&2):10-17

The present study was carried out to develop biodegradable intrascleral implants of Dexamethasone Sodium Phosphate and to evaluate the release pattern of the drug from the prepared implants. Intrascleral implants were prepared by using biodegradable polymer L-PLA (m.wt. 61,200 Da). Sodium chloride (NaCl), gelatin and glycerol monostearate (GMS) were used in various formulations to observe the effects of these additives on the release of Dexamethasone Sodium Phosphate from the prepared L-PLA based intrascleral implants. Five different formulations were prepared for this study and were coded as FD-1 (10%drug+L-PLA), FD-2 (20%drug+L-PLA), FD-3 (10%drug+L-PLA+5%NaCl), FD-4 (10%drug+L-PLA +5%Gelatin) and FD-5 (10%drug+L-PLA+10% GMS). Discs were prepared and made into appropriate shape before submerging into the buffer solution of pH 7.4 in different vials. The in vitro release profile of Dexamethasone Sodium Phosphate from the implants showed a biphasic release pattern with an initial burst followed by a diffusive phase. It was observed that FD-1 and FD-2 showed 19.63% and 29.87% release on the first day and 24.22% and 38.5% release respectively at day 30. The drug loading of FD-1 and FD-2 was 10% and 20% respectively. Among FD-3, FD-4 and FD-5; FD-3 showed highest release (32.1%) at day 30 in which 5% NaCl was used. FD-4 showed 27.45% release at day 30 where gelatin, a hydrophilic agent was used and FD-5 containing GMS, a lipid material, was found to be most retarding (19.22% at day 30). The results of the dissolution study provide an idea that L-PLA may be successfully used for the preparation of biodegradable intrascleral implant of Dexamethasone Sodium Phosphate. Key words: Dexamethasone Sodium Phosphate; Bioidegradable polymer; Intrascleral implants. DOI: 10.3329/sjps.v2i1.5817Stamford Journal of Pharmaceutical Sciences Vol.2(1) 2009: 56-60