Intracellular Delivery of Biologically Active Proteins with Peptide-Based Carriers

The medical applications of protein-based therapeutics are hampered by low bioavailability associated with inefficient intracellular delivery. Various delivery materials have been developed and tested to interact with protein cargos in a manner of stabilizing proteins extracellularly and facilitating cellular uptake of proteins, thus enhancing delivery efficiency. Peptides that can form stable complexes with proteins through non-covalent interaction appear to be a promising tool to improve intracellular delivery of proteins. Here we describe the preparation of complexes formed between β-galactosidase and peptide-based carrier, protein transfer of the complexes, and the methods to evaluate delivery efficiency qualitatively and quantitatively.