Biocompatible Polymeric Nanoparticles From Castor Oil Derivatives via Thiol‐Ene Miniemulsion Polymerization

Biocompatible polymeric nanoparticles are obtained via thiol‐ene polymerization of a biobased monomer in miniemulsion. The α,ω‐diene‐diester monomer is synthesized through esterification reaction of a glycerol derivative, namely 1,3‐propanediol, with 10‐undecenoic acid, a long‐chain diene carboxylic acid. In order to investigate how different monomeric structures behave toward thiol‐ene polymerization in miniemulsion, two types of thiols are investigated: 1,4‐butanedithiol and 2‐mercaptoethyl ether. Poly(thioether‐ester)s with weight average molecular weight up to 15 kDa (M n ) are obtained, depending on initiator concentration and types of surfactant and dithiol employed. Finally, biobased poly(thioether‐ester) nanoparticles are submitted to cytotoxicity and hemolysis analyses. High cell viability and no significant changes in cell morphology are observed after the incubation on murine fibroblast (L929) and human cervical cancer cells (HeLa). Last, hemolysis assays revealed blood compatibility and therefore polymeric nanoparticles have been shown to be a potential alternative drug delivery vector for intravenous administration. Practical Applications : There is a great demand for polymeric systems that fulfill a number of requirements, such as biodegradability and biocompatibility, for biomedical applications. In this context, biobased polymers obtained from vegetable oils are a very attractive sustainable alternative to fossil‐derived polymeric materials, presenting potential biodegradability and low toxicity. By thiol‐ene reactions, polymeric materials containing ester groups in the main chain—which can undergo hydrolysis—can be prepared in miniemulsion, enabling their degradation in physiological environment and, therefore, being interesting for biomedical applications and material disposal. Such novel materials could be used in temporary implants, tissue engineering, and drug delivery systems. Biocompatible polymeric nanoparticles are obtained via thiol‐ene polymerization of a biobased monomer in miniemulsion. Nanoparticles revealed to be a potential alternative controlled release drug delivery vector for intravenous administration.