Polymeric Vectors for Strategic Delivery of Nucleic Acids

Abstract

Genomic modification through nucleic acid delivery is a frequently applied method in fundamental biological studies and offers a potent therapeutic strategy for disease treatment and biological research. Delivery of nucleic sequences is therefore an attractive facet of biological nanotechnology as highly specific, efficient, and nonantagonistic delivery is necessary for in vivo and clinical use. Previous vectors have suffered from immunogenic responses, serum dependent inactivation, and cytotoxicity, hindering their translational applicability. Current research in polymeric-based nucleotide delivery strives to offer a highly biocompatible, broad use vector through the utilization of polypeptide and polyamine conjugation that can be easily tailored for specific targeting or wide dissemination. Cross-linking low molecular weight polyamines and lipophilic derivatization for amphiphile creation has lead to improved biocompatibility and transfection efficiency compared to higher molecular weight polyamines. Derivatization of hyperbranched and dendritic polyamido- and polyamines has allowed for the formation of efficient in vivo transfection vectors; ring opening synthesis of N-carboxyanhydride amino acids have led to controlled peptide architectures for improved transfection while simultaneously providing convenient primary amines useful in functionalization. Polymer libraries of poly(ß-amino esters) have provided insights into useful architectures for in vitro and in vivo gene delivery. Grafting small molecules to polyamines, such as folate and galactose, for enhanced interaction with cell surface receptors for selective targeting of specific cell types has proven to be encouraging and remains a prominent aspect in biological nanotechnology.