One-step preparation of biocompatible amphiphilic dimer nanoparticles with tunable particle morphology and surface property for interface stabilization and drug delivery

Biocompatible amphiphilic nanoparticles (NPs) with tunable particle morphology and surface property are important for their applications as functional materials. However, previously developed methods to prepare amphiphilic NPs generally involve several steps, especially an additional step for surface modification, greatly hindering their largescale production and widespread applications. Here, a versatile one-step strategy is developed to prepare biocompatible amphiphilic dimer NPs with tunable particle morphology and surface property. The amphiphilic dimer NPs, which consist of a hydrophobic shellac bulb and a hydrophilic poly(lactic acid) (PLA) bulb with PLA-poly(ethylene glycol) (PEG) on the bulb surface, are prepared in a single step by controlled co-precipitation and self-assembly. Amphiphilic PLA-PEG/shellac dimer NPs demonstrate excellent tunability in particle morphology, thus showing good performances in controlling the interfacial curvature and emulsion type. In addition, temperature-responsive PLA-poly(N-isopropyl acrylamide) (PNIPAM)/shellac dimer NPs are prepared following the same method and emulsions stabilized by them show temperature-triggered response. The applications of PLA-PEG-folic acid (FA)/shellac dimer NPs for drug delivery have also been demonstrated, which show a very good performance. The strategy of preparing the dimer NPs is green, scalable, facile and versatile, which provides a good platform for the design of dimer NPs with tunable particle morphology and surface property for diverse applications.