Green synthesis and characterization of poly(glycerol‐azelaic acid) and its nanocomposites for applications in regenerative medicine

Abstract

A series of novel bio-polyester nanocomposites based on glycerin and azelaic acid as monomers incorporating hydroxyapatite (HA) nanoparticles were fabricated via in situ polymerization method. Chemical structure of the samples was investigated by 1 H-NMR, 13 C-NMR, and Fourier-transform infrared spectroscopy (FTIR). Energy dispersive X-ray-mapping analysis illustrated that the nanoparticles were well dispersed in the poly (glycerol azelaic acid) (PGAZ) matrix. Viscoelastic properties of the samples under various frequencies were examined in which the PGAZ specimen containing 1.0 wt% of HA nanoparticles (PGAZH1.0) exhibited superlative properties. Furthermore, the alterations in the glass transition temperature of the samples were comprehensively discussed. Thermal gravimetric analysis displayed that nanocomposites generally have a difference in degradation patterns from that of the pristine sample. Dynamic contact angle demonstrated that the presence of HA nanoparticles imposed a significant influence on hydrophilicity. The hydrolytic degradation values at pH = 7 and pH = 11 were measured and determined that the degradation rate for the PGAZ sample containing 1.5 wt% HA (PGAZH1.5) was higher than those of the other samples. Moreover, in vitro studies elucidated that cell attachment on PGAZH1.0 and PAZH1.5 surfaces were acceptable.

Preparation and characterization of a new bio nanocomposites based poly(glycerol sebacic‐urethane) containing nano‐clay (Cloisite Na+) and its potential application for tissue engineering

“…As well, sebacic acid exhibited characteristic bands at 931 cm −1 (OH bending vibration), 1297 cm −1 (CO stretching vibration), and 1697 cm −1 (CO stretching vibration). Regarding the pre‐PGS FTIR spectrum (Figure 1C), the presence of characteristic absorption bands at 1094 and 1162 cm −1 (CO vibrations), a distinct peak at 1730 cm −1 (CO stretching vibration), absorption bands at 2932 and 2853 cm −1 (methyl groups), and a broad peak at 3120–3650 cm −1 (hydroxyl groups) implied the successful synthesis of pre‐PGS 21,39 …”

“…The tests' results were represented as mean ± SD (standard deviation); all data were generated from at least three independent Regarding the pre-PGS FTIR spectrum (Figure 1C), the presence of characteristic absorption bands at 1094 and 1162 cm À1 (C O vibrations), a distinct peak at 1730 cm À1 (C O stretching vibration), absorption bands at 2932 and 2853 cm À1 (methyl groups), and a broad peak at 3120-3650 cm À1 (hydroxyl groups) implied the successful synthesis of pre-PGS. 21,39 After adding HDI and completing the curing process, the broad peak of hydroxyl groups of PGS pre-polymer shifted to a narrower peak at 3332 cm À1 ( NH of urethane groups), with a shoulder at 3520 cm À1 ( OH groups of PGSU). Comparing with pre-PGS, the absorption bands belong to amide groups can be seen in the spectrum of PGSU located at 1621 cm À1 (amide I), 1536 cm À1 (amide II), and 1248 cm À1 (amide III), 21 implying the successful formation of urethane linkages owing to the chemical reaction between HDI and pre-PGS hydroxyl groups.…”

“…PGS pre-polymer and PGSU film was synthesized following our previously published papers 21,39 with some modification. Briefly, the pre-PGS synthesis was started by mixing glycerol and sebacic acid (equimolar) at 130 C under a nitrogen atmosphere for 1 h. The pressure was then reduced, and the reaction was allowed to continue for 24 h to yield a yellow viscose resin.…”

Azelaic Acid: A Bio-Based Building Block for Biodegradable Polymers

“…In neutral conditions, the weight loss of the samples over 30 days was monitored and the gradually decrease of the samples in time was attributed to the interactions of water molecules with ester bonds but the incorporation of the nanoparticles led to strengthening the weight loss and hydrolytic degradation rate. At pH 11, a more accelerated decrease of the mass was observed, which was attributed to possible hydrolysis in the presence of the hydroxylic ions, but for the nanocomposites the hydrolysis rate was slowed and the weight fraction mass was about 30% higher compared to the sample without the nanoparticles [ 116 ].…”

Conductive poly(ε‐caprolactone)/polylactic acid scaffolds for tissue engineering applications: Synergy effect of zirconium nanoparticles and polypyrrole

“…Over the past decades, bio-polyesters have been attracted considerable attention among all synthetic biomaterials considering their desirable biocompatibility and their hydrolytically unstable ester bonds, making them a high potential candidate for biomedical applications. 3 PCL is one of the popular polyesters in tissue engineering, which has been widely used to fabricate polymeric nanocomposites due to its high biocompatibility, suitable degradation rate, and ability to blend with a broad range of polymers. 4,5 Overall, PLA possesses lower hydrophilicity, better mechanical strength, and a faster hydrolytic degradation rate than PCL.…”