Overview

• The material uses cucurbit[n]uril host–guest complexes with pH-dependent kinetic locking that alters crosslinking and stiffness.
• In dye-release tests under compression, the gel released 32% more cargo at pH 5.5 than at pH 7.5 over three hours.
• Responsivity is tuned across a physiological pH window of roughly 4.5–7.5, matching the local acidosis characteristic of inflamed joints.
• The autonomous system relies on the body’s chemistry rather than external triggers, targeting drug release to inflamed tissue to limit systemic exposure.
• The proof-of-concept, published in the Journal of the American Chemical Society, now advances to in vivo studies to assess biocompatibility, safety and efficacy.