Bovine serum albumin（BSA） was utilized to assemble with the binary complexes of poly（vinylpyrrolidone）-graft-poly（2- dimethylaminoethyl methacrylate）（PVP-g-PDMAEMA）/DNA formed by layer-by-layer electrostatic interactions to screen the residual surface positive charges of complexes.The coating of BSA was able to decrease the zeta potential of binary complexes nearly to electroneutrality without interfering with DNA condensation ability.The ternary complexes of BSA/PVP-g-PDMAEMA/ DNA demonstrated lower cytotoxicity compared with the binary complexes and also maintained high gene transfection efficiency in HepG2 cells.
Biao ZhangLian Dong DengJin Feng XingJun YangAn Jie Dong
Bovine serum albumin （BSA） was modified through a facile synthesis method to increase its isoelectric point （pl） from 4.8 to 6.0. When pH is higher than 6.0, the protein shows a negative surface charge, on the contrary, the protein is positively charged. In this study, the charge-reversal modified BSA （crBgA） was utilized to assemble with the binary complexes of pDNA/poly（vinylpyrrolidone）-graft-poly（2- dimethylaminoethyl methacrylate） （pDNA/PVP-g-PDMAEMA） to shield the excess positive charges of complexes at physiological pH （pH 7.4）. When the complex coated with crBSA located in the environment at endosomal pH （pH 5.0）, the charge-reversal of crBSA led to the deviation of crBSA from polyplex by electrostatic repulsion, which would benefit the transfection of the target gene. The crBSA shows great potential for improving the transfection efficiency of ~DNA/PVP-^-PDMAEMA.
Ning ZhangChong-Xi WangJin-Hao LiuJin-Feng XingAn-Jie Dong
