DNA nanotechnology was used to interface with proteins through DNAprotein hybrid molecules for protein detection and protein intracellular delivery. EZZ protein, which can bind to almost all IgG antibodies, was selected to be conjugated to DNA linker. Different methods of DNA-protein conjugation were used to develop universal adapters between IgG antibodies and DNA. Using DNA nanobarcodes, which is based on the color ratios of two colors rather than using different colors, a library of IgG-based nanobarcodes were generated through a simple mixing step. The IgG-based nanobarcodes were used as a platform to simultaneously detect target proteins in different systems, including microbead-based, membrane-based, and tissue-based. Moreover, for the first time, a new concept of using DNA transfection reagents was introduced to deliver proteins intracellularly with great efficiency.