Int. J. Pharm. Sci. Rev. Res., 21(1), Jul – Aug 2013; n° 44, 270-275 ISSN 0976 – 044X International Journal of Pharmaceutical Sciences Review and Research Available online at www.globalresearchonline.net 270 Kumaraswamy Santhi 1 * , Sokalingam Arumugam Dhanaraj 1 , Abdul Nazer Ali 2 , M ohamed Sherina 3 1. Unit of Pharmaceutics and Unit of Pharmacy Practice, Faculty of pharmacy, AIMST University, Semeling, Kedah state, Malaysia. 1. K.Santhi, M.Pharm, PhD, senior associate professor Unit of Pharmaceutical technology, Faculty of Pharmacy, Aimst University, semeling, Kedah state, Malaysia. 1. S.A Dhanaraj, M .Pharm, PhD, Professor and Dean, Faculty of Pharmacy, Aimst University, semeling 08100 Kedah state, M alaysia. 2. Abdul Nazer Ali, M .Pharm, Associate professor, Unit of Pharmacy Practice, Aimst University, semeling 08100 Kedah state, Malaysia. 3. M .Sherina, M .Pharm, Grace College of Pharmacy, Koduthurapully, Palakkad, Kerala, India. Accepted on: 25-04-2013; Finalized on: 30-06-2013. ABSTRACT A great deal of attention has been given to the formulation of alginate micro beads which has potential as carrier in controlled drug delivery. The drug Nifedipine has low bioavailability, hence to improve its bioavailability; Nifedipine-loaded mucoadhesive microbeads were prepared by Ionotropic gelation and cross linking technique by using sodium alginate as the hydrophilic carrier in combination with Guar gum as release modifier. Micro beads with different ratio of sodium alginate and guar gum were formulated and evaluated for particle size, swelling ratio, and percentage yield. An optimized batch was selected from the previous study and four different concentrations of Nifedipine were loaded. The drug loaded batches were evaluated for drug entrapment, bio adhesiveness, in vitro release, and release kinetics. Particle size distribution of beads was measured by both optical microscopy and SEM. No significant drug-polymer interactions were observed in FT-IR studies. In-vitro drug release profile of Nifedipine micro beads in phosphate buffer pH 6.8 exhibited zero order release with kinetics of super case II-transport .The in vitro wash-off test using goat intestine revealed that the sodium alginate micro beads of Nifedipine possess good mucoadhesive properties. The drug loaded batches were found to have good drug loading. Hence the formulated Microbeads of Sodium alginate with guar gum as release modifiers could be used as an alternative and cost effective carrier for the development of oral controlled release capsules or tablets the of Nifedipine as once daily formulation. Keywords: Nifedipine, sodium alginate, micro beads, Ionotropic gelation, Guar gum, release modifier. INTRODUCTION ifedipine is used in the management of various cardio vascular diseases in long term therapy. Still it has various disadvantages such as low bioavailability and frequent dosing through conventional dosage forms. This problem can be attenuated by designing the drug in the form of mucoadhesive beads eventually it would prolong the drug residence time at the site of absorption so as to enhance the bio adhesiveness and thereby the bioavailability 1, 2 . Oral multiparticulate drug-delivery syst em s offer biopharmaceutical advantages such as free dispersion and predictable distribution in the intestine. 3, 4 Beads with lowest shrinkage and highest mechanical strength could be prepared from alginates having high content of a-L- guluronic acid. 5 By the selection of appropriate type of alginate, cross linking agent, and release modifiers, (coating agents) the alginate beads of various morphology, mechanical strength, distinct porosity, dehydration, and drug loading capacity can be fabricated 6 . This high degree of flexibility can result in delivery of drugs over extended period of time ranging from minutes to months in a sustained manner 7 When administrated orally via immediate-release solid dosage forms, absorption of Nifedipine is poor . Therefore, preparation of modified release formulation may be beneficial in reduction of dose and dose related side effects. 8 The cross linking property of alginate beads make them attractive as a suitable bio polymer for the encapsulation of wide variety of drugs including proteins, DNA Oligo nucleotides, proteins, cardio vascular drugs like Verapamil, Diltiazem, and Nicardipine, anti- inflammatory drugs like Diclofenac sodium, Aceclofenac, Ibuprofen etc, and even stem cells. 9, 10 The aim of the present investigation is to optimize the suitable concentration of guar gum as release modifier for microbeads so as to make a micro bead carrier system ready for the development of controlled release capsules or tablets the for the modified oral delivery of Nifidipine. M ATERIALS AND M ETHODS M aterials Nifedipine was a gift sample from Alkem Pharmaceuticals Ltd, Mumbai. All other chemicals like sodium alginate, Guar gum, calcium chloride and glutraldehyde were from Nice chemicals, Bangalore, India. Other reagents used were of analytical grade. Double distilled water was used throughout the study. Drug-Polymer compatibility study This study was carried to find out the possible interaction between the selected polymers like sodium alginate, Guar gum with the drug Nifedipine and also to identify the compatibility between the drug and the polymer. Small Formulation and Evaluation of Nifedipine M icrobeads Using Guar gum as a Release M odifier N Research Article