title: Microdevice for on-site fish freshness checking based on K-value measurement.
abstract: An electrochemical microfluidic device with two sensing sites in the upper and lower streams of a flow channel was fabricated to measure the K-value as a means of evaluating the freshness of fish. In this device, plugs of solutions were processed using mechanisms to place a plug at the sensing site and to merge and mix two plugs in a single flow channel. The sums of ATP-related compound concentrations used for the calculation of the K-value were measured at the first and second sensing sites. The ratio of the output currents agreed well with the K-value calculated from predetermined concentrations in standard solutions. The K-values of jack mackerel, yellow tail, and sea bream extracts were then obtained using the device and were found to agree well with those obtained by high-performance liquid chromatography (HPLC). In addition, the changes in the K-value with time were observed to depend strongly on the type of fish for these three fish extracts.
authors.affiliation: Graduate School of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Itoh
authors.forename: Eri
authors.initials: E
authors.lastname: Koyachi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Yokokawa
authors.forename: Yuko
authors.initials: Y
authors.lastname: Murata
authors.forename: Masakazu
authors.initials: M
authors.lastname: Murata
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Suzuki
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D005399:Fishes; D005504:Food Analysis / Q000379:methods*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*
chemical_list: D000255:Adenosine Triphosphate