Nanotechnology, among others, has great potential in the field of medicine and pharmacy because nanoobjects have comparable dimensions to biological entities (e.g. cells, DNA etc.). Polymers like polylactides (PLA), polyglycolides (PGA), poly(lactide-co-glycolides) (PLGA), poly(DL-lactide-co-glycolides) (DLPLG) are approved by the World Health Organization and Food and Drug Administration as materials that can be used in medicine and pharmacy. Polymeric particles are used for the controlled delivery of several classes of medicaments like anticancer agents, antihypertensive agents, immunomodulatory drugs, hormones and macromolecules like nucleic acid, proteins, peptides, antibodies, etc.
Controlled drug delivery occurs when a polymer is judiciously combined with a drug or other active agent in such a way that the active agent is released from the material in a predesigned manner. The release of the active agent may be constant over a long period, it may be cyclic over a long period, or it may be triggered by the environment or other external events. In any case, the purpose behind controlling the drug delivery is to achieve more effective therapies while eliminating the potential for both under- and overdosing. Other advantages of using controlled-delivery systems can include the maintenance of drug levels within a desired range, the need for fewer administrations, optimal use of the drug in question, and increased patient compliance.
One of the basic requirements for the controlled and balanced release of the medicament in the body is its ideal spherical shape of the polymer particles and narrow distribution of their sizes. The size and shape of the particles play key role in their adhesion and interaction with the cell. Polymer degradation, also, plays a key role in medicament release from sustained release polyester systems, therefore in order to elucidate the mechanism governing release, it appears essential to analyse the in vitro degradation behaviour of these devices.
The researchers at the Institute of Technical Sciences of the Serbian Academy of Sciences and Arts have developed a new physico-chemical method with solvent/non-solvent systems enabling easily control of the morphology and sizes of the polymeric particles. The encapsulation of the medicaments in the polymer matrix is performed by homogenization of water and organic phases. The degradation of micro and nanospheres and release rate of medicaments has been tracked in vitro in different degradation medium. In vivo experiments are to follow.