Preparation and evaluation of cholesteryl PAMAM dendrimers as nano delivery agents for antisense oligonucleotides

Cholesterol conjugated dendrimers were prepared at increasing ratios of cholesterol to the surface amines of dendrimer and characterized their structural features. The delivery efficiency of antisense oligonucleotide into cells was evaluated by using a splicing correction assay. The cholesteryl dendrimers prepared at a mole ratio of 5:1 formed biologically active complexes with antisense oligonucleotides and mediated delivery of antisense oligonucleotide into HeLa cells in a moderate level. The enhanced delivery of the antisense oligomer into nucleus of the cell resulted in the expression of the reporter gene product, a luciferase. Our data confirmed that the increase in hydrophobicity by the conjugation of cholesterol to dendrimer enhanced the delivery efficiency of antisense oligonucleotide into cells.