Sulfonated Azocalix[4]arene: A Universal and Effective Taste-Masking Agent.

Many active pharmaceutical ingredients have a specific bitter taste. To enhance patient compliance and treatment efficacy, taste-masking agents are crucial in oral drug formulations. Confronting numerous bitter drug molecules with varied structures, the pharmaceutical field strives to explore and develop universal and effective masking approaches. Here, we reported sulfonated azocalix[4]arene (SAC4A), a universal supramolecular masking agent with deep cavity that provides stronger hydrophobic effect and larger interaction area during recognition, allowing high binding affinity to bitter drug molecules. Moreover, bitter drugs could deeply buried in the cavity, with the bitterness effectively masked. As a result, SAC4A can bind to 16 different bitter drugs with high affinities, encompassing alkaloids, flavonoids, terpenoids, and more, while maintaining high biocompatibility. As anticipated, SAC4A effectively masks the unpalatable bitter taste associated with these drugs. Consequently, SAC4A is a promising universal and effective supramolecular masking agent.