The main goal of any drug delivery system is to achieve desired concentration of the drug in blood or tissue, which is
therapeutically effective and nontoxic for a prolonged period. Various attempts have been made to develop gastroretentive
delivery systems such as high density system, swelling, floating system. The recent developments of FDDS including the
physiological and formulation variables affecting gastric retention, approaches to design single-unit and multiple-unit
floating systems, and their classification and formulation aspects are covered in detail. Gastric emptying is a complex
process and makes in vivo performance of the drug delivery systems uncertain. In order to avoid this variability, efforts
have been made to increase the retention time of the drug-delivery systems for more than 12 hours. The floating or
hydrodynamically controlled drug delivery systems are useful in such application. Background of the research: Diltiazem
HCL (DTZ), has short biological half life of 3-4 h, requires rather high frequency of administration. Due to repeated
administration there may be chances of patient incompliance and toxicity problems. Objective: The objective of study was
to develop sustained release alginate beads of DTZ for reduction in dosing frequency, high bioavailability and better patient
compliance. Methodology: Five formulations prepared by using different drug to polymer ratios, were evaluated for
relevant parameters and compared. Alginate beads were prepared by ionotropic external gelation technique using CaCl2
as cross linking agent. Prepared beads were evaluated for % yield, entrapment efficiency, swelling index in 0.1N HCL,
drug release study and SEM analysis. In order to improve %EE and drug release, LMP and sunflower oil were used as copolymers
along with sodium alginate.
Formulation Development of Pulsatile Drug Delivery of Tiotropium Bromide
