292DESIGN AND CHARACTERIZATION OF AMBROXOL HYDROCHLORIDE SUSTAINED RELEASE MICROBEADSAmbroxol Hydrochloride is a mucolytic agent used in variety of respiratory disorders. The major problem associated with this therapy is short half-life of the drug which necessitates frequent dosing of 2 to 3 times daily. The objective of the present investigation is to develop, formulate and characterize sustained release microbeads of Ambroxol Hydrochloride to prolong the release rate so as to decrease the necessity of multiple dosing and to increase the patient compliance. The beads were prepared by varying concentrations of sodium alginate and calcium chloride using ionotropic gelation technique.Prepared beads were evaluated for granulometric studies, micrometric, scanning electron microscopy, drug entrapment efficiency and invitro dissolution studies etc., The Scanning electron microscopy studies showed beads were spherical and uniform. The angle of repose was in the range of 20° - 30° showing that the beads had good flow property. The drug content and entrapment efficiency of the drug were good. The loose surface crystal studies revealed that as the concentration of sodium alginate increased the amount of the drug present in surface decreases which showed an increase in entrapment of drug in the bead. The size of the beads and swelling properties were also studied. The effect of sodium alginate and calcium chloride were studied on the release rates. The drug release was sustained as the polymer concentration is increased. The release rates were proportional to the sodium alginate and calcium chloride concentration. Based on the studies FC2 (3.5% sodium alginate with 2% calcium chloride) was found to be the best formulation. This lead formulation was evaluated for further studies.The drug release obeyed first order kinetics. The Kosemeyer-Peppas plot, the „n‟ value is found to be 0.494, non-fickian diffusion.The stability studies indicated no changes when maintained at400C ± 20C,75% ± 5%RH for 3 months. rajalakshmig67@gmail.comResearch492013Kosemeyer, Non fickian,Loose surface crystal studies,Granulometric,MicrometricG.Rajalakshmi,Rajyalakshmi Dhulipati,N.DamodharanDepartment of Pharmaceutics, SRM College of Pharmacy, Kattankulathur, Kanchepuram 603203, Tamilnadu, India.,Department of Pharmaceutics, SRM College of Pharmacy, Kattankulathur, Kanchepuram 603203, Tamilnadu, India.,Department of Pharmaceutics, SRM College of Pharmacy, Kattankulathur, Kanchepuram 603203, Tamilnadu, India.