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Thiol‐ene polymerization has been pointed out as a promising technique to produce biobased polymers for biomedical applications due to its advantages, including mild conditions and rapid reaction rates without the formation of byproducts. Therefore, in this study different concentrations of magnetic nanoparticles (MNPs) were incorporated in poly(thioether‐ester) (PTEE) nanoparticles by thiol‐ene miniemulsion polymerization of biobased monomers to form both linear and branched cross‐linked polymers. Loading efficiencies up to approximately 95% (thermogravimetric analysis) of the MNPs within the polymer matrix were obtained. In addition, the substitution of the dithiol 1,4‐butanedithiol (64.2%) for the tetrathiol PTEMP (95.8%), increased the encapsulation efficiency by about 30%. Hybrid nanoparticles presented average mean diameters between 95 and260 nm with polydispersity index between 0.13 and 0.42 by DLS, negative zeta potentials around −45 mV and superparamagnetic behavior. The hyperthermia assays performed on breast cells (MDA‐MB 231) have shown that the cell death was dependent on the exposure time to the AC magnetic field and the reduction in cell viability was approximately 35%. These results demonstrated the production of superparamagnetic PTEE nanoparticles via thiol‐ene polymerization and highlight the promising application of these biobased materials for cancer treatment by hyperthermia. [ABSTRACT FROM AUTHOR]

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 (Mn) 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. [ABSTRACT FROM AUTHOR]