IMPROVEMENTS IN AND RELATING TO SENSORS

摘要

The invention provides a sensor for sensing an anion, the sensor comprising a piezoelectric crystal microbalance, preferably a quartz crystal microbalance, on which is immobilised a complexant, the complexant having at least one cation binding site and, when said at least one cation binding site is occupied by a cation, at least one anion binding site. Preferably, the complexant is immobilised in a membrane composition. Advantageously, the sensor may be selective for pertechnetate and/or chromate. There is also provided a method of sensing an anion in a liquid medium, the method comprising providing the sensor according to the invention, exposing the microbalance to the liquid; and, measuring the output of sensor. The concentration of the anion may be determined from frequency and/or voltage measurements on the microbalance.