Boronic acid-rich dendrimer for efficient intracellular peptide delivery

Interests in intracellular peptide delivery have continued to grow, significantly fueled by the importance of peptides and their mimetics in modern cell biology and pharmaceutical industry. However, efficient intracellular delivery of membrane-impermeable peptides of different polarities remains a challenging task. In this study, we develop a general and robust strategy for intracellular peptide delivery by using a boronic acid-rich dendrimer. The designed material is capable of transporting peptides with different polarities and charge properties into the cytosol of various cell lines without inducing additional cytotoxicity. The transduction efficacy and proteolytic stability of cargo peptides delivered by the boronic acid-rich dendrimer are much superior to peptides conjugated with cell penetrant peptides such as octaarginine. In addition, the bioactivities of pro-apoptotic peptides are maintained after intracellular delivery. This study provides a versatile and robust platform for the intracellular delivery of membrane-impermeable peptides.