High-throughput identification of combinatorial ligands for DNA delivery in cell culture

Finding the optimal combinations of ligands for tissue‐specific delivery is tedious even if only a few well‐established compounds are tested. The cargo affects the receptor‐ligand interaction, especially when it is charged like DNA. The ligand should therefore be evaluated together with its cargo. Several viruses have been shown to interact with more than one receptor, for efficient internalization. We here present a DNA oligonucleotide‐based method for inexpensive and rapid screening of biotin labeled ligands for combinatorial effects on cellular binding and uptake. The oligonucleotide complex was designed as a 44 bp double‐stranded DNA oligonucleotide with one central streptavidin molecule and a second streptavidin at the terminus. The use of a highly advanced robotic platform ensured stringent processing and execution of the experiments. The oligonucleotides were fluorescently labeled and used for detection and analysis of cell‐bound, internalized and intra‐cellular compartmentalized constructs by an a...