Synthesis of Gemcitabine-Loaded PLGA Microparticles with Green Solvents

The use of polymeric microparticles is widely recognized as an effective strategy for enhancing the bioavailability and biodistribution of both lipophilic and hydrophilic medications. In this study, PLGA microparticles loaded with the anticancer drug gemcitabine were synthesized by using a double emulsion process known as water-in-oil-in-water solvent evaporation. Notably, this is the first time that ethyl lactate, an FDA-approved green solvent, has been used for the microparticle synthesis. For comparison, other solvents, such as ethyl acetate and dichloromethane, were also tested. The smallest particle size was achieved, regardless of the PLA:PGA ratio of the polymer, when using ethyl lactate under the following operational conditions: a high homogenizer speed (12,000 rpm) and an initial polymeric solution concentration of 1.5% w/v. Under these conditions, the encapsulation efficiency reached 45% for PLGA 50:50 and 35% for PLGA 75:25. Microparticle analysis revealed a homogeneous distribution (100-150 μm range) and a spherical shape. Furthermore, Fourier transform infrared (FTIR) spectroscopy confirmed the presence of gemcitabine in the microparticles.