Tansel Comoglu
Ankara University, Turkey
Title: Effect of formulation variables on entrapment efficiency of Levodopa loaded PLGA nanoparticles
Biography
Biography: Tansel Comoglu
Abstract
Parkinson's is a major neurodegenerative disorder that occurs due to loss of dopaminergic neurons in basal ganglia. Conventional therapy includes surgery that involves a lot of risk and administration of levodopa which is accompanied by poor bioavailability, short half-life, and side effects. In this present study, poly(lactic-co-glycolic acid) (PLGA) nanoparticles-based drug delivery system to improve the bioavailability of the drug was evaluated. Nanoparticles were prepared by double emulsion solvent evaporation technique (w/o/w). The process of encapsulation of drugs by double emulsion/evaporation in a matrix of PLGA can be divided into three successive steps: first, an aqueous solution of the active compound is emulsified into an organic solution of the hydrophobic coating polymer; second, this primary water-in-oil emulsion (w/o) is dispersed in water with formation of a double water-oil-water emulsion (w/o/w); third, the organic solvent is removed with formation of solid particles. In our study, the effect of inner phase, evaporation time and polymers’ moleculer weight on entrapment efficiency were evaluated. In the experiment, 5% poly vinyl alcohol is used as outer phase and 2 mL dichloromethane is used as the oil phase. The drug encapsulation efficiency were measured by high performance liquid chromatography (HPLC). 10 μl of supernatant was injected into an Agilent 1100 liquid chromatograph to determine the actual amounts of Levodopa non-incorporated within the nanoparticles. Separation was achieved using a C18 column (250 mm × 4.6 mm, 5 μm) at a flow rate of 1.0 ml/min and a detection of 280 nm. All the analysis was performed at 25°C. An increase in the encapsulation efficiency was observed in the nanoparticles prepared with PLGA with the lower molecular weight, showing that PLGA with the lower molecular weight effectively trapped Levodopa. When 1% Tween 80 solution was used in the inner phase with a 20 mM HCl solution a shortened evaporation time and an increased drug encapsulation were observed.