Sustained Release Bilayer Tablet of Ibuprofen and Phenylephrine Hydrochloride: Preparation and Pharmacokinetics in Beagle Dogs

Core-shell tablets designed for modified and sequential release of ibuprofen and rabeprazole

In this study, core-shell tablets comprising an ibuprofen (IBU) enteric-coated core for modified release and a rabeprazole (RAB) shell for immediate release were developed using wet granulation method. The primary aim was to produce a sequential release of RAB and IBU with pharmacokinetic profiles comparable to those of the respective single tablets, thereby reducing the potential for IBU-associated gastrointestinal (GI) side effects. The composition of the IBU/RAB core-shell tablets was finalized on a comparative basis by evaluating various trial formulations. IBU/RAB core-shell tablets (400/20 mg) were assessed for physicochemical attributes, storage stability, and in vivo pharmacokinetics in beagle dogs. IBU/RAB core-shell tablets showed immediate RAB release (99.5 % in 1 h at pH 1.2) and delayed IBU release (3.4 % and 88 % in the acid and buffer stages, respectively). IBU/RAB core-shell tablets produced either comparable or improved plasma concentrations in dogs (Cmax; 1163.3 vs. 1160.0 ng/mL for RAB and 27,370 vs. 24,170 ng/mL for IBU) compared to those of the respective single tablets. The IBU/RAB core-shell tablets also demonstrated long-term and accelerated storage stability. In conclusion, the core-shell design could be a promising strategy for the co-administration and sequential release of IBU and RAB to relieve inflammatory conditions and reduce GI complications.

Bilayer fixed-dose combination tablet for curcumin microparticles and piroxicam and in vitro evaluation

Aim: In the present work, fixed-dose combination of bilayer tablets for piroxicam as and curcumin as immediate-release and sustained-release layer (SRL) respectively for management of inflammatory response. Materials & methods: The SRL include Curcumin polycaprolactone microparticles from spray drying. The tablet layers include Pearlitol 200SD, Microcrystalline cellulose PH101, Aerosil 200, talc each layer. Results: SEM studies confirm spherical microparticles. PXRD and DSC studies confirm the amorphous microparticles. In vitro studies exhibit, an immediate release and sustained release for Piroxicam and Curcumin after 2 h. Cellular uptake studies on RAW 264.7 cells confirm the complete internalization of microparticles. Conclusion: Therefore, it was concluded that microparticles can be formulated into a unit dosage form for the management of inflammation.

Robustness of Controlled Release Tablets Based on a Cross-linked Pregelatinized Potato Starch Matrix

The aim of this study was to evaluate the potential of a cross-linked pregelatinized potato starch (PREGEFLO® PI10) as matrix former for controlled release tablets. Different types of tablets loaded with diprophylline, diltiazem HCl or theophylline were prepared by direct compression of binary drug/polymer blends. The drug content was varied from 20 to 50%. Two hydroxypropyl methylcellulose grades (HPMC K100LV and K100M) were studied as alternative matrix formers. Drug release was measured in a variety of release media using different types of experimental set-ups. This includes 0.1 N HCl, phosphate buffer pH 6.8 and water, optionally containing different amounts of NaCl, sucrose, ethanol or pancreatin, fasted state simulated gastric fluid, fed state simulated gastric fluid, fasted state simulated intestinal fluid, fed state simulated intestinal fluid as well as media simulating the conditions in the colon of healthy subjects and patients suffering from Crohn's disease. The USP apparatuses I/II/III were used under a range of operating conditions and optionally coupled with the simulation of additional mechanical stress. Importantly, the drug release kinetics was not substantially affected by the investigated environmental conditions from tablets based on the cross-linked pregelatinized potato starch, similar to HPMC tablets. However, in contrast to the latter, the starch-based tablets roughly kept their shape upon exposure to the release media (they "only" increased in size) during the observation period, and the water penetration into the systems was much less pronounced. Thus, the investigated cross-linked pregelatinized potato starch offers an interesting potential as matrix former in controlled release tablets.