SENSOR AND METHOD FOR DETECTING PREDETERMINED CHEMICAL SPECIES IN SOLUTION

摘要

A chemical sensor for measuring a change in the sensor mass relating to the interaction of a surface of the sensor with a solution comprises a crystal detector oscillator capable of providing a measurement signal based upon the resonant frequency of the crystal detector oscillator. The crystal detector oscillator has a first crystal side for contacting the solution, and a second crystal side isolated from contacting the solution. A first electrode is integral to the first crystal side, with the first electrode having an inner and outer perimeter defining an outer portion of the first crystal side which is exterior to the outer perimeter of the first electrode and an inner portion of the first crystal side which is interior to the inner perimeter of the first electrode. A second electrode is integral to the second crystal side. The sensor may be employed to detect the concentration of predetermined species in solution by adsorbing a predetermined species-specific complementary material such as an antibody onto the active crystal sites of the first crystal side, and thereafter contacting the first crystal side with the species-containing solution, thereby causing adsorption of molecules of the predetermined species onto the complementary material-adsorbed active crystal sites. The difference in the measured resonant frequencies of the complementary material-adsorbed sensor and the complementary material plus species-adsorbed sensor is indicative of and may be correlated with the concentration of the predetermined species in solution. The sensor may also be used to measure the change in sensor mass relating to the degradation of a coating applied to the first crystal side thereof. The apparatus of the invention comprises the chemical sensor operatively coupled to detecting means for detecting the resonant frequency of the crystal detector oscillator and providing a detector output signal representative of the crystal detector oscillator resonant frequency. The apparatus may additionally comprise display means operatively coupled to the sensor detecting means for displaying the detector output signal.