Synthesis of polylactide/poly(ethylene glycol) diblock copolymers with functional endgroups

Anticancer Biosurfactant-Loaded PLA-PEG Nanoparticles Induce Apoptosis in Human MDA-MB-231 Breast Cancer Cells

Despite various advancements in cancer therapies, treating cancer efficiently without side effects is still a major concern for researchers. Anticancer drugs from natural sources need to be explored as a replacement for chemo drugs to overcome their limitations. In our previous studies, isolation, characterization, and anticancer properties of a novel biosurfactant from Candida parapsilosis were reported. In this study, we report the cytotoxicity of the polymeric nanoparticles of this novel biosurfactant toward breast cancer cells. Biosurfactant-encapsulated polymeric nanoparticles of polylactic acid-poly(ethylene glycol) (PLA-PEG) copolymers were synthesized by the double emulsion solvent evaporation method. Folic acid (FA) was used as a targeting ligand to actively deliver the anticancer cargo to the cancer site. The encapsulation efficiency of nanoparticles was observed as 84.9%, and Fickian diffusion was observed as a kinetic model for the release of biosurfactant from nanoparticles. The controlled delivery of the biosurfactant was noticed when encapsulated in PLA-PEG copolymer nanoparticles. Additionally, it was observed that FA enhanced the uptake and cytotoxicity of biosurfactant-loaded nanoparticles in MDA-MB-231 cancer cells compared to biosurfactant-loaded plain nanoparticles. Induction of apoptosis was observed in cancer cells by these nanoparticles. We explore a potential anticancer agent that can be further analyzed for its efficiency and can be used as an alternative tool.

Development of Polymer Coacersome Structure with Enhanced Colloidal Stability for Therapeutic Protein Delivery

Poly(ethylene arginyl aspartate diglyceride) (PEAD) polycation is widely used to prepare coacervate particles by electrostatic complexation with an anionic heparin (HEP) in aqueous environments, for controlled release of therapeutic proteins. However, coacervate complexes aggregate randomly due to particle-particle charge interactions. Herein, a new term "coacersome" is introduced to represent a stable polyplex formed by complexation of mPEGylated PEAD and HEP. Methoxy polyethylene glycol (mPEG)-b-cationic PEAD diblock copolymers are synthesized and complexed with HEP to create a stable "coacersome" structure. Water-soluble mPEG moiety assembles on the surface of coacersomes in aqueous conditions and creates a steric barrier to avoid aggregation of coacersomes. The coacersomes are able to maintain their initial spherical morphology and size for longer durations in the presence of competing ions, such as 0.3 m NaCl. Additionally, the coacersomes exhibit biocompatibility toward human dermal fibroblasts, a high loading efficiency (>96%) for encapsulation of bone morphogenetic protein 2 (BMP-2), and a sustained release profile up to 28 days. The BMP-2-loaded coacersomes further exhibit increased osteogenic differentiation of human mesenchymal stem cells (hMSCs). The developed coacersome structures have the potential to be utilized as effective carriers for therapeutic protein delivery.