s A Double-Emulsion Method for the Fabrication of PLA Single-Hole Hollow Particles

Background: Polymeric hollow particles with a single-hole structure have attracted broad interest due to their combined advantages of a hollow cavity and an opening hole in the shell. Aim: In the past decades, much progress has been made in the fabrication of such particles with various strategies. However, there is a lack of research on the easy fabrication of biodegradable polylactide (PLA) single hole particles (PLA SHHPs). Methods: In this work, we reported a simple double emulsion method for the fabrication of PLA SHHPs. The W/O/W double emulsion was formed by homogenizing PLA chloroform and brilliant blue G (BBG) solution. Scanning electron microscopy and confocal laser scanning microscopy were used for the characterization. It was found that the concentrations of PLA chloroform and BBG solution both had a significant influence on the emulsion structure. Results: PLA SHHPs with a percentage >85% were obtained from the emulsion composed of PLA chloroform (10.0 w%) and BBG solution (4 mM). The particle formation mechanism was also proposed based on the result of the low interfacial tension between PLA chloroform/BBG solution. Conclusion: The results may inspire new development of PLA particles with unique structures, which are promising to be used in drug delivery, catalysis, microreaction and micromotors.