A system and methods for controlled gene delivery comprising condensed nucleic
acids complexed with polylinkers, wherein the complexes are covalently and/or non-covalently
bound to the surface of a substrate capable of supporting cell adhesion. The gene
delivery system achieves temporal and spatial control of nucleic acid delivery
to a target cell or cells through control of complex density on the surface of
the support substrate, and reversibility of the attachment of the polylinker to
the support substrate. The system and method of the invention can be used to create
spatial patterns of gene expression, and in tissue engineering, high throughput
screening, and gene therapy applications.