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There is an increasing need to develop bio‐compatible polymers with an increased range of different physicochemical properties. Poly(glycerol‐adipate) (PGA) is a biocompatible, biodegradable amphiphilic polyester routinely produced from divinyl adipate and unprotected glycerol by an enzymatic route, bearing a hydroxyl group that can be further functionalized. Polymers with an average Mn of ∼13 kDa can be synthesized without any post‐polymerization deprotection reactions. Acylated polymers with fatty acid chain length of C4, C8, and C18 (PGAB, PGAO, and PGAS, respectively) at different degrees of substitution were prepared. These modifications yield comb‐like polymers that modulate the amphiphilic characteristics of PGA. This novel class of biocompatible polymers has been characterized through various techniques such as FT‐IR, 1H NMR, surface, thermal analysis, and their ability to self‐assemble into colloidal structures was evaluated by using DLS. The highly tunable properties of PGA reported herein demonstrate a biodegradable polymer platform, ideal for engineering solid dispersions, nanoemulsions, or nanoparticles for healthcare applications. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3267–3278

No abstract

A novel class of biodegradable polyesters has been generated by coupling poly(glycerol adipate) with N-acyl aromatic amino acids. This new set of polymers from this highly versatile polymeric platform may offer unprecedented new opportunities to produce biodegradable and biocompatible polymers with tailorable physical-chemical properties.

In this study, the grafting of nicotinic acid and p-aminobenzoic acid (PABA) onto poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) was performed by Huisgen's 1,3-dipolar cycloaddition, also known as click chemistry. Concentrations used for grafting were 0.10, 0.20, and 0.30 molar ratios with respect to caproyl units. The grafted copolymers were successfully obtained at all ratios as confirmed by NMR, GPC, and FT-IR. According to the DSC results, the polymorphisms of these grafted copolymers were mostly changed from semicrystalline to amorphous depending on the type and the amount of grafting compounds. TGA thermograms showed different thermal stabilities of the grafted copolymers compared to the original copolymers. Cytotoxicity results from HUVEC models suggested that the toxicity of grafted nanoparticles increased with the molar ratios of grafting units. Due to differences in molecular structure between nicotinic acid and PABA, physicochemical properties (particle size and surface charge) of grafted copolymer nanoparticles were substantially different. With increasing molar ratio of the grafting units, the particle size of blank nanoparticles tended to increase, resulting from an increase in the hydrophobic fragments of the grafted copolymer. Ibuprofen was chosen as a model drug to evaluate the interaction between grafted copolymers and loaded drug. After ibuprofen loading, the particle size of the loaded nanoparticles of both grafted copolymers increased compared to that of the blank nanoparticles. Significant differences in loading capacity between nicotinic acid and PABA grafted copolymer nanoparticles were clearly shown. This is most likely a result of different compatibility between each grafting compound and ibuprofen, including hydrogen bond interaction, π-π stacking interaction, and steric hindrance.