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Development and characterization of an all-solid-state potentiometric biosensor array microfluidic device for multiple ion analysis.

Wei-Yin Liao·Chen-Hsun Weng·Gwo-Bin Lee·Tse-Chuan Chou
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Abstract

A microfluidic device with an all-solid-state potentiometric biosensor array was developed using microfabrication technology. The sensor array included a pH indicator, and potassium and calcium ion-selective microelectrodes. The pH indicator was an iridium oxide thin film modified platinum microelectrode and the iridium oxide was deposited by an electrochemical method. The potassium and calcium ion-selective microelectrodes were platinum coated with silicon rubber based ion-selective membranes with respectively potassium (valinomycin) and calcium (ETH 1001) ionophores. The detection system was integrated with a micro-pneumatic pump which can continuously drive fluids into the microchannel through sensors at flow rates ranging from 52.4 microl min(-1) to 7.67 microl min(-1). The sensor array microfluidic device showed near-Nernstian responses with slopes of 62.62 mV +/- 2.5 mV pH(-1), 53.76 mV +/- 3 mV -log[K+](-1) and 25.77 mV +/- 2 mV -log[Ca2+](-1) at 25 degrees C +/- 5 degrees C, and a linear response within the pH range of 2-10, with potassium and calcium concentrations between 0.1 M and 10(-6) M. In this study the device provided a convenient way to measure the concentration of hydrogen, potassium and calcium ions, which are important physiological parameters.

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Biosensing TechniquesCalciumDiaminesHydrogen-Ion ConcentrationMembranes, ArtificialMicroelectrodesMicrofluidic Analytical TechniquesPotassiumPotentiometryValinomycinJournal ArticleResearch Support, Non-U.S. Gov't

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Wei-Yin Liao, Chen-Hsun Weng, Gwo-Bin Lee, Tse-Chuan Chou. 2006-08-14. Development and characterization of an all-solid-state potentiometric biosensor array microfluidic device for multiple ion analysis.. https://doi.org/10.1039/b603364d

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