A new approach to the development of quartz crystal sensors distinguishing between mass loading and liquid damping

Characteristic damping coefficient K/sub c/ is introduced to distinguish between the effects of mass loading and liquid damping of a quartz resonator vibrating in liquids. When the mass loading of the quartz resonator is constant the value of /spl kappa//sub c/ depends only on the parameters of the resonator itself and not on the properties of the attached mass or liquid. The effect of mass loading can be distinguished from that of liquid damping by measuring the frequency shift and the amplitude of the quartz resonator simultaneously. A series of experiments were carried out to test the value of /spl kappa//sub c/, and the influence of the resonator parameters on /spl kappa//sub c/ was studied, e.g., the electrode area, the harmonic number, and the fundamental frequency.

[1]  Chao Zhang,et al.  Contributions of amplitude measurement in QCM sensors , 1996 .

[2]  S. J. Martin,et al.  Sensing liquid properties with thickness-shear mode resonators , 1994 .

[3]  P. Woias,et al.  HIV serology using piezoelectric immunosensors , 1994 .

[4]  V. M. Mecea,et al.  Loaded vibrating quartz sensors , 1994 .

[5]  K. Weil,et al.  Influence of the Surface Microstructure on the Coupling Between a Quartz Oscillator and a Liquid , 1992 .

[6]  Stephen J. Martin,et al.  Characterization of a quartz crystal microbalance with simultaneous mass and liquid loading , 1991 .

[7]  C. Barnes,et al.  A concanavalin A-coated piezoelectric crystal biosensor , 1991 .

[8]  P. Woias,et al.  Biosensors based on piezoelectric crystals , 1990 .

[9]  Isao Karube,et al.  Computation of equivalent circuit parameters of quartz crystals in contact with liquids and study of liquid properties , 1988 .

[10]  J. Gordon,et al.  The oscillation frequency of a quartz resonator in contact with liquid , 1985 .

[11]  Toshiaki Nomura,et al.  Frequency shifts of piezoelectric quartz crystals immersed in organic liquids , 1982 .

[12]  G. Bastiaans,et al.  Piezoelectric crystals as detectors in liquid chromatography , 1980 .

[13]  V. Mecea,et al.  The mechanism of the interaction of thin films with resonating quartz crystal substrates: The energy transfer model , 1979 .

[14]  R. Mueller,et al.  Direct Gravimetric Calibration of a Quartz Crystal Microbalance , 1968 .

[15]  G. Sauerbrey Verwendung von Schwingquarzen zur Wägung dünner Schichten und zur Mikrowägung , 1959 .

[16]  G. Sauerbrey,et al.  Use of quartz vibration for weighing thin films on a microbalance , 1959 .