Novel Cesium Membrane Sensor Based on a Cavitand

A PVC‐based membrane sensor was prepared for Cs + ions, which was based on 7,11,15,28‐tetraiodo‐1,21,23,25‐tetramethyl‐2,20:3,19‐dimethano‐1H,21H,23H,25H‐bis[1,3]dioxocino[5,4‐i:5′,4′i′] benzo[1,2‐d:5,4‐d′]‐bis[1,3]benzodioxocin stereoisomer (cavitand). The proposed membrane electrode exhibits a linear dynamic range of 1.0 × 10 −;1 –1.0 × 10 −;5 M, with a Nernstian slope of 59.1 ± 0.3 mV per decade, and a detection limit of 5.0 × 10 −;6 M. It has a very fast response time of <10 s and can be used for at least eight weeks without any considerable divergence in its potentials. The best sensor performance was obtained with a membrane containing 30% PVC, 62% dibutylphthalate (DBP), 6% cavitand, and 2% potassium tetrakis( p ‐chlorophenyl) borate (KTpClPB). The sensor could be used in a pH range of 4.3–9.5.