Formulation and evaluation of metformin hydrochloride microspheres
Mono or multi nuclear materials embedded in spherical coating matrix are called microspheres. Microspheres are solid, approximately spherical particles ranging in size from 1µm to 1000µm .These are made of polymeric, waxy or other protective materials that are biodegradable synthetic polymers and modified natural products such as starches, gums, proteins fats, and waxes.Microspheres are small and have large surface to volume ratios. At the lower end of their size range they have colloidal properties.