In vitro prolonged gastric residence and sustained release of atenolol using novel clay polymer nanocomposite

Atenolol (ATN) is a widely prescribed drug for the treatment of hypertension. Due to short biological half life, low oral bioavailability and poor absorption-from the lower gastrointestinal tract high doses are required to maintain its therapeutic level in the blood plasma which has undesirable side effects. It seems that an increase in gastric residence time may increase the extent of absorption and bioavailability of the AN. Therefore, to overcome the drawbacks associated with conventional oral delivery of ATN, a new drug delivery vehicle is required. The purpose of the present research was to develop montmorillonite (Mt)-poly lactic-co-glycolic acid (PLGA) nanocomposites as sustained release oral delivery vehicle for AM. The Mt-PLGA nanocomposites were prepared by w/o/w double emulsion solvent evaporation method by varying the AN to Mt ratio at three levels using Pluronic F68 and PLGA as stabilizing agent and matrix material respectively. Effects of these compositions on interlayer spacing of Mt-PLGA nanocomposites, particle size, morphology and in vitro drug release were evaluated. The in vitro release behavior of ATN from Mt-ATN-PLGA nanocomposites was found to be pH dependent and sustained as compared to ATN-PLGA nanoparticles, pure ATN and commercial formulation of Atenolol ATEN-25 over a period of 24 h. The developed clay polymer nanocomposites (CPN) show promising ability to prolong the gastric residence time of AN and suggest the possibility of designing the sustained release formulations with improved bioavailability and patient compliance. (C) 2015 Elsevier B.V. All rights reserved.