Bis-Boronic Acid Liposomes for Carbohydrate Recognition and Cellular Delivery

Liposomes are effective therapeutic nanocarriers due to their ability to encapsulate and enhance the pharmacokinetic properties of a wide range of drugs and diagnostic agents. A primary area in which improvement is needed for liposomal drug delivery is to maximize the delivery of these nanocarriers to cells. Cell membrane glycans provide exciting targets for liposomal delivery since they are often densely clustered on cell membranes and glycan overabundance and aberrant glycosylation patterns are a common feature of diseased cells. Herein, we report a liposome platform incorporating bis-boronic acid lipids (BBALs) to increase valency in order to achieve selective saccharide sensing and enhance cell surface recognition based on carbohydrate binding interactions. In order to vary properties, multiple BBALs (1 a-d) with variable linkers in between the binding units were designed and synthesized. Fluorescence-based microplate screening of carbohydrate binding showed that these compounds exhibit varying binding properties depending on their structures. Additionally, fluorescence microscopy experiments indicated enhancements in cellular association when BBALs were incorporated within liposomes. These results demonstrate that multivalent BBALs serve as an exciting glycan binding liposome system for targeted delivery.