Research Journal of Pharmaceutical Dosage Form and Technology

N. L. Prasanthi ¹, S. S. Manikiran ², C. Sowmya Krishna ², N. Rama Rao ²

Affiliations
1 Department of Pharmaceutics, Chalapathi Institute of Pharmaceutical Sciences, Lam, Guntur- 522034 Andhra Pradesh, IN
2 Chalapathi Institute of Pharmaceutical Sciences, Lam, Guntur- 522034 Andhra Pradesh, IN

Abstract

Aquasomes are one of the most recently developed delivery systems; these are nanoparticulate carrier systems with three-layered self-assembled structures. They comprise a central solid nanocrystalline core coated with polyhydroxyoligomers onto which biochemically active molecules are adsorbed. Three types of core materials are mainly used for producing aquasomes: tin oxide, nanocrystalline carbon ceramics (diamonds) and brushite (calcium phosphate dihydrate). Calcium phosphate is the core of interest, owing to its natural presence in the body. The brushite is unstable and converts to hydroxyapatite upon prolong storage. Hydroxyapatite seems, therefore, a better core for the preparation of aquasomes. It is widely used for the preparation of implants for drug delivery. The solid core provides the structural stability, while the carbohydrate coating protects against dehydration and stabilizes the biochemically active molecules. This property of maintaining the conformational integrity of bioactive molecules has led to the proposal that aquasomes have potential as a carrier system for delivery of peptide, protein, hormones, antigens and genes to specific sites.

Keywords

Aquasomes, Nanoparticels, Bioactives, Nanocrystalline Core.

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K. M. Lokamatha Swamy ¹, D. Manjula ², S. M. Shanta Kumar ¹, N. Rama Rao ¹, Somshekar Shyale ¹, R. Suma ¹

Affiliations
1 Department of Pharmaceutics, V.L. College of Pharmacy, Raichur- 584103, Karnataka, IN
2 Dayananda Sagar College of Pharmacy, Shavige Malleshwara Hills, Kumarswamy layout, Bangalore-560078, Karnataka, IN

Abstract

The objective of this study was to develop, characterize and evaluate mucoadhesive microcapsules of flurbiprofen with a coat consisting of sodium alginate in combination with other mucoadhesive polymers such as sodium carboxy methylcellulose (sodium CMC), methyl cellulose (MC), carbopol and hydroxy propyl methyl cellulose (HPMC) by an emulsification-ionic gelation process for prolonged gastrointestinal absorption. The microcapsules were prepared by an emulsification-ionic gelation process. The microcapsules were evaluated for physical characteristics such as particle size, particle shape and surface morphology by scanning electron microscopy, and other parameters like drug entrapment efficiency, in vitro mucoadhesion by everted intestinal sac technique and in vitro drug release characteristics. The USP Rotating Basket method was selected to perform the dissolution profiles carried out in 900 ml of phosphate buffer of pH 7.2. The resulting microcapsules were discrete, small, and fairly spherical and free flowing. Microencapsulation efficiency was 60.92% to 87.74% and relatively high with alginate-carbopol and low with alginate-MC combinations. On the contrary, alginate-carbopol shown lower strength of mucoadhesion and high percentage of mucoadhesion was observed with alginate-MC combination. Flurbiprofen release from these mucoadhesive microcapsules was slow, extended over longer periods of time and depended on the combination of mucoadhesive polymer. The highest percentage of drug release was observed with alginate-hydroxy propyl methyl cellulose. Drug release kinetics from these formulations corresponded best to Higuchi model. The release of the model drug from these mucoadhesive microcapsules was prolonged over an extended period of time and the drug release mechanism followed anomalous (non- Fickian) diffusion controlled as well as Case II transport. By providing intimate contact of dosage form with the absorbing surface, bioavailability of drug could enhanced which in turn improves pharmacological effect. As a result, oral controlled release dosage form to avoid serious gastrointestinal adverse effects commonly associated with the model drug was achieved by the principle of mucoadhesion.

Keywords

Flurbiprofen, Hydroxy Propyl Methyl Cellulose, Sodium Carboxy Methyl Cellulose, Methyl Cellulose, Microcapsules.

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K. Ravi Sankar ¹, N. L. Prasanthi ², S. S. Manikiran ², N. Rama Rao ²

Affiliations
1 Aurobindo Pharma Ltd., Hyderabad, IN
2 Chalapathi Institute of Pharmaceutical Sciences, Lam, Guntur- 522034, IN

Abstract

Roxithromycin, an antibacterial agent is widely used in the treatment of various infections. One of the major problem with this drug is its low solubility in biological fluids. Therefore, solid dispersions of roxithromycin were prepared using mannitol as carrier by different techniques like physical mixing, melting method, melt solvent method, kneading technique and common solvent method to improve the aqueous solubility. Solid dispersions were prepared in 1:1, 1:2, 1:4 and 1:9 ratios of drug to carrier. Prepared solid dispersions were evaluated for solubility, content uniformity, dissolution rate and efficiency. More solubility and faster dissolution was exhibited by solid dispersions containing 1:4 ratio of drug and carrier prepared by melting method. FT-IR studies revealed the absence of significant drug-carrier interactions.

Keywords

Roxithromycin, Mannitol, Solid Dispersions, Solubility.

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