Hybrid Cavitand−Resorcin[4]arene Receptor for the Selective Binding of Choline and Related Compounds in Protic Media

A hybrid cavitand−resorcin[4]arene receptor capable of displaying pH-modulated binding affinity toward trimethylalkylammonium ions is proposed as an alternative to the low selectivity exhibited by other receptors used in supramolecular fluorescent sensor systems for choline.