Contrast effect on hydrolysis of poly(trimethylene carbonate) depending on accelerated species due to the hydrophilic oligo(ethylene glycol) units at side groups

Biodegradable smart materials with self-healing and shape memory function for wound healing

Notwithstanding the rapid development of suture elastomers to meet the needs of practical surgery, utilizing the elastomers' self-healing function as a surgical suture to facilitate the healing of wounds has not been addressed. Here, a biodegradable aliphatic polycarbonate smart elastomer, mPEG₁₁₃-b-PMBC _n , was synthesized from aliphatic polycarbonate monomer with methoxy polyethylene glycol (mPEG₁₁₃, 5.0 kDa) as initiator, which exhibited excellent mechanical properties, highly efficient self-repairing, and remarkable shape memory behavior. The polymers possess outstanding self-healing ability for 150 min. Meanwhile, after 46.33 ± 1.18 s, the temporary shape of the obtained polymer had been recovered. The results of biocompatibility tests reveal that the polymers have excellent biocompatibility and can be regarded as good biomedical materials. Then, in vivo experiments were used to prove the self-healing knotting ability of the polymers and quickly close a wound surface using a programmed shape at physiological temperature. The results demonstrated that the injury wound can be effectively healed compared with traditional sutures, which will offer new study suggestions for subsequent healing areas.

In Vivo Degradation Mechanisms of Aliphatic Polycarbonates and Functionalized Aliphatic Polycarbonates

Aliphatic polycarbonates (APCs) have been studied for decades but have not been as utilized as aliphatic polyesters in biomaterial applications such as drug delivery and tissue engineering. With the recognition that functionalized aliphatic polymers can be readily synthesized, increased attention is being paid to these materials. A frequently provided reason for utilizing these polymers is that they degrade to form diols and carbon dioxide. However, depending on the structure and molecular weight of the APC, degradation may not occur. In this review, the mechanisms by which APCs and functionalized APCs have been found to degrade in vivo are examined with the objective of providing guidance in the continued development of these polymers as biomaterials.

Mass spectrometry in bioresorbable polymer development, degradation and drug-release tracking

A detailed characterization of polymeric matrices and appropriate degradation monitoring techniques are required to sustain the development of new materials as well as to enlarge the applications of the old ones. In fact, polymer analysis is essential for the clarification of the intrinsic relationship between structure and properties that ascertains the industrial applications in diverse fields. In bioresorbable and biodegradable polymers, the role of analytical methods is dual since it is pointed both at the polymeric matrices and at degradation tracking. The structural architectures, the mechanical and morphological properties, and the degradation rate, are of outstanding importance for a specific application. In some cases, the complexity of the polymer structure, the processes of decomposition or the low concentration of the degradation products need the concurrent use of different complementary analytical techniques to give detailed information of the reactions taking place. Several analytical methods are used in bioresorbable polymer development and degradation tracking. Among them, mass spectrometry (MS) plays an essential role and it is used to refine polymer syntheses, for its high sensitivity, to highlight degradation mechanism by detecting compounds present in trace amounts, or to track the degradation product profile and to study drug release. In fact, elucidation of reaction mechanisms and polymer structure, attesting to the purity and detecting defects as well as residual catalysts, in biodegradable and bioresorbable polymers, requires sensitive analytical characterization methods that are essential in providing an assurance of safety, efficacy and quality. This review aims to provide an overview of the MS strategies used to support research and development of resorbable polymers as well as to investigate their degradation mechanisms. It is focused on the most significant studies concerning synthetic bioresorbable matrices (polylactide, polyglycolide and their copolymers, polyhydroxybutyrate, etc.), published in the last ten years.