SOME NEW CONCEPTS ON FACTORS INFLUENCING THE OPERATIONAL FREQUENCY OF LIQUID-IMMERSED QUARTZ MICROBALANCES

Currently available theories for determining the operational frequency of liquid-immersed quartz microbalances are briefly summarized. The importance of the type of oscillator circuit is stressed. An analysis is given, together with experimental evidence, which suggests that when operating the crystal at parallel resonance, the dielectric properties of the immersion medium may under appropriate conditions outweigh the traditional viscoelastic mechanisms in determining the final operating frequency. Finally, the implications for biosensing are discussed.