Scientists at Yale and the University of Rhode Island report the development of a peptide that can specifically and directly deliver molecules to the inside of cells like a nanosyringe, creating a new tool for drug delivery, gene control and imaging of diseased tissues.
Their "cargo carrier" peptide called pHLIP, for pH (Low) Insertion Peptide, accumulates in the membranes of cells in acidic environments and spontaneously transfers attached molecules across the membrane. The cargo is then released by cleavage of a sulfur-sulfur bond that is only unstable if it is inside the cell.