Neurotrophic factor loaded polymeric microspheres from microfludic technique for potential biomedical applications

•Preparation of GDNF-loaded CPMS via microfluidic technology.•Analysis of CPMS microstructure, encapsulation efficiency, and biocompatibility.•CPMS induce PC12 cell differentiation and sustain bioactivity for six weeks. In this study, we prepared GDNF-loaded PLGA microspheres using the double emulsion solvent evaporation method. The freeze-dried PLGA microspheres were combined with a Chitosan Methacryloyl(CSMA) solution and subsequently processed using microfluidic technology to produce CSMA/PLGA Composite Microspheres (CPMS) of varying sizes. The optimized CPMS, characterized by specific aqueous and oil flow rates, exhibited a diameter of 73.2 ± 4.5 μm, with an encapsulation efficiency and drug loading capacity of 81.2 ± 1.9 % and 0.84 ± 0.11 %, respectively. Surface and structural characterization of CPMS via SEM and LSCM revealed their quasi-spherical shape and multicore structure encapsulating PLGA microspheres. Results from Live/Dead cell staining and CCK-8 cell assays suggest that CPMS exhibit excellent biocompatibility. Furthermore, GDNF-ELISA and PC12 cells differentiation assays indicate that CPMS released GDNF sustainably, promoting PC12 cells differentiation and maintaining biological activity for at least six weeks.