Abstract

BUOYANT MULTIPARTICULATE DRUG DELIVERY - A FOCUS ON HYDROGEL BEADS

Ganesh N. S.*, G.Bharathi, Hanumanthachar Joshi, Jayanthi C., Devendra Pratap Singh.

Sarada Vilas College of Pharmacy, K.M.Puram, Mysore, Karnataka, India.

ABSTRACT

Gastric emptying is a complex process that makes in vivo performance of drug delivery systems uncertain; however the floating or hydrodynamically controlled drug delivery systems namely, floating microspheres, microbeads, microcapsules etc., are useful in overcoming such uncertainty. Microbeads are small, solid and free flowing particulate carriers containing dispersed drug particles both in solution or crystalline form, formulated from both synthetic and natural polymers and can be in the size range of millimeter, micrometer or nanometer. The size largely depends on the type of polymer and the methodology adopted. The drug is incorporated into beads either during formulation or adsorbed to pre-formed beads like dynabeads. Hydrocolloids are polymeric substances that alter the rheology of aqueous solutions in which they are dispersed and the resulting beads are called hydrogel beads. In this review, commonly employed polymers and various techniques for the formulation of hydrogel beads are discussed in detail and the applications of hydrogel beads in stomach specific drug delivery, protein drug delivery, enzyme immobilization, carriers for plant growth promoting bacteria etc., are summarized.

Keywords: Microbeads, Gastro-retentive, Hydrocolloids, Hydrogel, Controlled drug delivery.