Multichannel wireless-electrodeless quartz-crystal microbalance immunosensor

We develop the wireless-electrodeless multichannel quartz-crystal microbalance (QCM) biosensor using quartz plates of slightly different thicknesses. Their shear vibrations are simultaneously excited and detected by a pair of antenna wires to perform the noncontacting measurement. Their fundamental resonance frequencies are between 43 and 55 MHz, and vibrations at up to 10 channels are measured in liquids. Owing to high affinity of naked quartz surfaces for proteins, we immobilized various receptor proteins on different quartz plates nonspecifically and detected various antigen-antibody reactions separately. The exponential coefficient of the frequency change, rather than the amount of the frequency decrease, is found to be useful for distinguishing between specific and nonspecific binding reactions.Hirotsugu Ogi, Hironao Nagai, Yuji Fukunishi, Taiji Yanagda, Masahiko Hirao, and Masayoshi Nishiyama. Multichannel wireless-electrodeless quartz-crystal microbalance immunosensor. Analytical Chemistry, 2010, 82(9), 3957-3962. ©2010 American Chemical Society. https://doi.org/10.1021/ac100527r