Preparation and Evaluation of Gastroretentive Floating Tablets of Silymarin

Abstract

The present study performed by preparation and evaluation of floating tablets of Silymarin as model drug for prolongation of gastric residence time. Floating effervescent tablets were formulated by various materials like hydroxypropyl methylcellulose (HPMC) K 4M, K 15M, psyllium husk, swelling agent as crospovidone and microcrystalline cellulose and gas generating agent like sodium bicarbonate and citric acid and evaluated for floating properties, swelling characteristics and in vitro drug release studies. Floating noneffervescent tablets were prepared by polypropylene foam powder and different matrix forming polymers like HPMC K 4M, Carbopol 934P, xanthan gum and sodium alginate. In vitro drug release studies were performed and drug release kinetics evaluated using the linear regression method was found to follow both the Higuchi and the Korsemeyer and Peppas equation. The drug release mechanism was found fickian type in most of the formulations. The developed floating tablets of Silymarin may be used in clinic for prolonged drug release for at least 24 h, thereby improving the bioavailability and patient compliance.

Preparation and <em>In-vitro</em> Evaluation of Gastroretentive Bupropion Hydrochloride Tablets

“…Highly viscous gels cause retardation of drug release [17,18]. Burst effect was observed in all the formulations due to rapid drug dissolution from the surface of the tablets.…”

Drug release kinetics and physicochemical characteristics of floating drug delivery systems

“…Reciprocal powered time [100] Silymarin Matrix tablets Effervescent and non-effervescent Higuchi and Korsemeyer--Peppas Rajinikanth and Mishra (2009) [110] Clarithromycin Alginate beads Effervescent Higuchi Balasubramaniam and co-workers (2008) [108] Clarithromycin Microspheres Mucoadhesive polymer Higuchi Bandari et al (2010) [94] Fenoverine Matrix tablets Effervescent Zero order Nagarwal et al (2010) [106] Cinnarizine Matrix tablets [73] Propranolol Matrix tablets…”

Formulation and Evaluation of Gastro-Bilayer Floating Tablets of Ezetimibe as Immediate Release Layer and Atenolol as Sustained Release Layer

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