During his graduate career he co-invented a class of responsive polymers for therapeutic applications. These materials were generated by modifying a water-soluble polymer, like dextran, with hydrophobic acetals. These could then be fashioned into stable microparticles, which could be degraded into biocompatible byproducts under the mildly acidic conditions like those found in lysosomal compartments. These materials showed promise for use in protein-based immunotherapy.
To complement these acid-degradable materials, he also developed a material specifically sensitive to the oxidizing environment found especially in the most potent targeting cells of the immune system.
He developed a system for drug delivery that featured all-or-nothing burst release kinetics. Capsules with impermeable walls could be stored indefinitely until exposed to even mildly acidic conditions, which would erode the walls and cause rupture.