Effect of surface chemistry on gene transfer efficiency mediated by surface-induced DNA-doped nanocomposites

Surface-induced biomineralization represents an effective way of immobilizing DNA molecules on biomaterial surfaces to introduce DNA into cells in contact with or at an approximate distance from the biomaterial surfaces. Previous studies have investigated how the composition of mineralizing solutions affects the composition and pH responsiveness of nanocomposites and thus gene transfer efficiency in different cell types. This study investigates how the functional groups of a biomaterial surface affect the induction and crystallographic properties of nanocomposites and thus the gene transfer efficiency. Self-assembled monolayers with different termini were used to control the functional groups of a surface. It is demonstrated that the induction of DNA-doped nanocomposites depends on the surface functional groups, which is consistent with previous studies. The crystallographic properties did not vary significantly with the functional groups. DNA-doped nanocomposites induced by different surface functional groups resulted in different cellular uptake of DNA and thus gene transfer efficiency. The differential cellular uptake may be attributed to the interactions between nanocomposites and functional groups. The weaker inducer resulted in higher cellular uptake, and thus higher gene transfer efficiency. Together with other previous studies, the current results suggest that surface-mediated gene transfer by DNA-doped nanocomposites can be modulated through both mineralizing solutions and surface chemistries.