PHYSICOCHEMICAL CHARACTERISATION OF DRUG POLYMER INTERACTIONS IN NANOPARTICLES

Abstract

Nanocapsules are vesicular systems in which the drug is confined to a cavity surrounded by a polymer membrane, whereas nanospheres are matrix systems in which the drug is physically and uniformly dispersed. Nanoparticles are solid, colloidal particles consisting of macromolecular substances that vary in size from 10 nm to 1000 nm. The drug of interest is dissolved, entrapped, adsorbed, attached or encapsulated into the nanoparticle matrix. Depending on the method of preparation, nanoparticles, nanospheres or nanocapsules can be obtained with different properties and release characteristics for the encapsulated therapeutic agent. Thus, to some extent, the effect of the nature of drug and polymer functional groups on polymer drug interactions could be investigated. These results could then be correlated to drug loading and release characteristics from various drug-polymer formulations. For both the amino acid substituted polymers ETO and ETO-P increased the Tm of the polymers. In the presence of PTx an increase in Tg of the polymer was recorded. The FT IR scan for PTx within the 40% acylated polymers did not show any significant difference compared to the empty polymers.