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Synthesis and properties of Polycaprolactone-graft-Poly(2-(dimethylamino)ethyl methacrylate-co-methoxy polyethylene glycol monomethacrylate) as non-viral gene vector

Polymers for Advanced Technologies (Impact Factor: 1.96). 12/2011; 22(12):1925 - 1930. DOI: 10.1002/pat.1694

ABSTRACT Polycaprolactone-graft-Poly(2-(dimethylamino)ethyl methacrylate-co-methoxy polyethylene glycol monomethacrylate) (PCL-graft-P(DMAEMA-co-mPEGMMA)) was synthesized by combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP). PCL-graft-P(DMAEMA-co-mPEGMMA) was characterized by FTIR, 1H NMR, and GPC. PCL-graft-P(DMAEMA-co-mPEGMMA) with expected composition and structure was achieved. pH- and thermo-sensitive properties of the PCL-graft-P(DMAEMA-co-mPEGMMA) nanoparticles prepared by the nanoprecipitation method were investigated by TEM and DLS. With increase in the temperature, the size of PCL-graft-P(DMAEMA-co-mPEGMMA) nanoparticles is decreased under base environment. Furthermore, in vitro transfection and toxicity assays were tested in 293T cells. The results indicate that PCL-graft-P(DMAEMA-co-PEGMMA) has lower cytotoxicity at N/P ratios less than 10 with transfection efficiency concomitantly reducing at N/P ratios less than 20 compared to PCL-graft-PDMAEMA as the control. However, PCL-graft-P(DMAEMA-co-PEGMMA) presents higher transfection efficiency at N/P ratios more than 20 compared to PCL-graft-PDMAEMA. Copyright © 2010 John Wiley & Sons, Ltd.

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