Synthesis and characterization of amine-functionalized amphiphilic block copolymers based on poly(ethylene glycol) and poly(caprolactone)

Solution processable polyamines via click chemistry for water purification

Highly stable amine functionalized polystyrenes were prepared and used for the removal of dissolved pollutants from water.

Catalyst-Free Plasma-Assisted Copolymerization of Poly(ε-caprolactone)-poly(ethylene glycol) for Biomedical Applications

Catalyst-free ring-opening polymerization (ROP) strategy was developed to overcome the disadvantage of incomplete and expensive removal of catalyst used during the multistep wet chemical processes. Nano-sized biocompatible and low molecular weight poly(ε-carolactone)-poly(ethylene glycol) (PCL-PEG) copolymer coatings were deposited via a single-step, low-pressure, pulsed-plasma polymerization process. Experiments were performed at different monomer feed ratio and effective plasma power. The coatings were analyzed by XPS, as well as MALDI ToF. Ellipsometric measurement showed deposition rates ranging from 1.3 to 3 nm/min, depending on the ratio of the PCL/PEG precursors introduced in the reactor. Our results have demonstrated that plasma copolymerized PCL-PEG coatings can be tailored in such a way to be cell adherent, convenient for biomedical implants such as artificial skin substrates, or cell repellent, which can be used as antibiofouling surfaces for urethral catheters, cardiac stents, and so on. The global objective of this study is to tailor the surface properties of PCL by copolymerizing it with PEG in the pulsed plasma environment to improve their applicability in tissue engineering and biomedical science.

Amphiphilic triblock copolymers of methoxy-poly(ethylene glycol)-b-poly(L-lactide)-b-poly(L-lysine) for enhancement of osteoblast attachment and growth

Amphiphilic triblock copolymers of methoxy-poly(ethylene glycol)-poly(L-lactide)-poly(L-lysine) (MPEG-b-PLLA-b-PLL) (Mn=8540-22 240) were synthesized through the ring-opening polymerization of Nepsilon-(Z)-lysine-N-carboxyanhydrides (N(epsilon)-(Z)-Lys-NCA) using MPEG-b-PLLA-NH2 as a macroinitiator. The triblock copolymers and diblock precursors were characterized by 1H NMR, ATR-FTIR, and GPC. The chain lengths of each block could be controlled by varying the feed ratios of the monomers. The surface properties of films of PLLA modified by blending with the triblock copolymers were investigated by XPS and AFM and demonstrated an enrichment of PLL blocks on the surface of the PLLA film. No cytotoxicity was detected on a range of modified PLLA films arising from the incorporation of the triblock copolymers. The triblock copolymers MPEG-b-PLLA-b-PLL showed better surface properties in promoting osteoblast adhesion and proliferation compared with pure PLLA and PLLA modified with MPEG-b-PLLA diblock copolymers. This study demonstrated that the triblock copolymers containing free amino groups, which self-segregate on the surface of biodegradable polyesters, have potential for applications in cell delivery and tissue engineering.