title: Multichannel wireless-electrodeless quartz-crystal microbalance immunosensor.
abstract: 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.
authors.affiliation: Graduate School of Engineering Science, Osaka University, Machikaneyama 1-3, Toyonaka, Osaka 560-8531, Japan. ogi@me.es.osakau.ac.jp
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ogi
authors.forename: Hironao
authors.initials: H
authors.lastname: Nagai
authors.forename: Yuji
authors.initials: Y
authors.lastname: Fukunishi
authors.forename: Taiji
authors.initials: T
authors.lastname: Yanagida
authors.forename: Masahiko
authors.initials: M
authors.lastname: Hirao
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Nishiyama
mesh_terms: D000818:Animals; D004566:Electrodes; D006801:Humans; D007118:Immunoassay; D011791:Quartz / Q000737:chemistry*
chemical_list: D011791:Quartz