Haemo‐ and cytocompatibility of bioresorbable homo‐ and copolymers prepared from 1,3‐trimethylene carbonate, lactides, and ϵ‐caprolactone

Abstract

A series of bioresorbable polymers were prepared by ring-opening polymerization of L-lactide (LLA), DL-lactide (DLLA), epsilon-caprolactone (CL) and 1,3-trimethylene carbonate (TMC), using low toxic zinc lactate as catalyst. The various PLLA, PTMC, PCL homopolymers, and PLLA-TMC, PDLLA-TMC, PCL-TMC copolymers with 50/50 molar ratios were characterized by using analytical techniques such as proton nuclear magnetic resonance, gel permeation chromatography, tensiometer, and differential scanning calorimetry. The haemo- and cyto-compatibility were investigated in order to evaluate the potential of the polymers as coating material in drug eluting stents. Haemolysis tests show that all the homo- and copolymers present very low haemolytic ratios, indicating good haemolytic properties. Adhesion and activation of platelets were observed on the surface of PLLA, PCL, PLLA-TMC, and PDLLA-TMC films, while less platelets and lower activation were found on PTMC. The most interesting results were obtained with PCL-TMC which exhibited the lowest degree of activation with few adhered platelets, in agreement with its outstanding anticoagulant properties. Both indirect and direct cytocompatibility studies were performed on the polymers. The relative growth ratio data obtained from the liquid extracts during the 6-day cell culture period indicate that all the polymers present very low cytotoxicity. Microscopic observations demonstrate adhesion, spreading and proliferation of human umbilical vein endothelial cells ECV304. Therefore, it is concluded that these bioresorbable polymers, in particular PCL-TMC, are promising candidate materials as drug loading coating material in drug eluting stents.

<italic>In vivo</italic> study on the histocompatibility and degradation behavior of biodegradable poly(trimethylene carbonate-co-d,l-lactide)

“…The polymer films were prepared with the method of heated-melt and mould fixation as previously reported [15][16][17][18]. The three kinds of polymer materials and 10% (w/v) dichloromethane were melted into collosols by heating and cast into the culture capsules, and fixed into the films with dimensions of 0.4 mmÂ10 mmÂ10 mm overnight, respectively.…”

“…In our previous reported work, various homo-and copolymers were synthesized from L-lactide, D, L-lactide, trimethylene carbonate, and e-caprolactone. Among them, PDLLA-TMC and PLLA-TMC present favorable in vitro degradable behavior, good cyto-compatibility, and mechanical properties [15][16][17][18]. In this work, we studied the in vivo degradation and histocompatibility of PLLA/TMC and PDLLA/TMC copolymers to explore the feasibility of manufacturing fully biodegradable cardiovascular stents.…”

Biodegradable poly(trimethylene carbonate‐b‐(L‐lactide‐ran‐glycolide)) terpolymers with tailored molecular structure and advanced performance

“…Many authors have claimed that the copolymerization of L ‐lactide ( L LA) with 1,3‐trimethylene carbonate (TMC) can be a successful route to modify both mechanical properties and biodegradation rate of P L LA . Hence, some copolymers based on L LA and TMC have been realized and used in commodity as high‐performance medical biomaterials …”

“…[26][27][28] Hence, some copolymers based on LLA and TMC have been realized and used in commodity as high-performance medical biomaterials. [29][30][31][32][33] In previous work, we have investigated PTMC-LLA copolymers synthesized by random copolymerization with different compositions and chain structures. [34][35][36] It appears that the incorporation of TMC component significantly enhances the toughness and reduces the acidity of degradation products compared with pure PLLA.…”

In vivo degradation of poly L-lactic D-lactic acid and tri-methylene carbonate sheets in orbital reconstruction

“…Yang et al [6] reported that hemolysis tests showed that all homopolymers and copolymers presented very low hemolytic ratios, indicating good hemolytic properties. Adhesion and activation of platelets were observed on the surface of polylactic acid, polycaprolactone (PCL), poly L-lactic acid (PLLA) and trimethylene carbonate (TMC) (PLLA-TMC), and poly-DL-lactide (PDLLA)-TMC films, while fewer platelets and less activation were found on poly(TMC).…”