Abstract

The effects of the tested factors including pH value, NaCl concentration, ODN concentration and charge ratio on the size and zeta potentials of nanoparticles (ODN-PLL, PLL: poly(l-lysine)s) were investigated by use of uniform design and NGR peptides were used to modify the nanoparticles, indicating that none of the tested factors was correlated with nanoparticles size, however, a linear correlation (r = 0.8505) was found between charge ratio and zeta potential. A nanosize delivery system (ODN-PLL-NGR) with the function of targeting to tumor cells was developed by use of PLL to condense oligonucleotide into nanoparticles coated with peptide containing NGR motif. The ODN-PLL-NGR had the ability to protect ODN against nuclease degradation, and its cell uptake increased with time increment after incubation at 37°C for 40, 50 and 60 min.

Keywords: Nanosize delivery system, Poly(l-lysine)s, tumor cells, NGR