The Effect of Processing Parameters on Characteristics of Poly-L-Lactide Microspheres



Biodegradable micro- and nanospheres made of poly-l-lactide (PLLA) are very potent drug or antigen delivery systems with inherent potential for drug and antigen targeting. The objective of this study is to formulate modified PLLA microparticles with defined size and shape that can efficiently bind bioactive component. The effects of some process variables on the size distribution of particles prepared by precipitation method are examined. The main focus is to study the effect of co-solvent selection and poly(vinyl alcohol) PVA concentration on the shape and size of the particles. Chlorophorm is used as a solvent. Methanol (MeOH) and ethanol (EtOH) are selected as co-solvents. Motivation for replacing MeOH with EtOH in pharmaceutical applications is explained by less harmful nature of EtOH. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to characterize the particles. Optimal particles are achieved in ethanol and at higher PVA concentration




Dragan P. Uskoković, Slobodan K. Milonjić and Dejan I. Raković




I. Jovanović et al., "The Effect of Processing Parameters on Characteristics of Poly-L-Lactide Microspheres", Materials Science Forum, Vol. 555, pp. 453-458, 2007


September 2007




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