A capillary flow immunoassay microchip utilizing inkjet printing-based antibody immobilization onto island surfaces-toward sensitive and reproducible determination of carboxyterminal propeptide of type I procollagen

• Published in: Journal of micromechanics and microengineering Vol. 26; no. 4; pp. 45015 - 45022
• Main Authors: Fuchiwaki, Yusuke, Tanaka, Masato, Takaoka, Hiroki, Goya, Kenji
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.04.2016
• Subjects: Antibodies; capirally; Channels; Grooves; Immobilization; Immunoassay; inkjet; Islands; Microchannels; point-of-care-testing; Quantitative analysis
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/26/4/045015

A capillary-flow-driven microchip system requires no external power and has no moving off-chip components, in contrast with most microfluidic-based immunoassay systems which are complicated to operate and require external components. To accelerate the sensitive and reproducible determination of analytes required for practical point-of-care applications, we formed island microchannel surfaces on a microcapillary channel to allow stable antibody immobilization. The island surface was surrounded by a circular groove 10 μm deep and 150 μm wide and allowed uniform inkjet printing of antibody spots, complete bio-reagent replacement, and sensitive detection of luminescence intensity. Quantitative analysis of carboxyterminal propeptide of type I procollagen (PICP) concentrations using this microchannel was demonstrated between 0-600 ng·ml−1, which is adequate for the clinical estimation of PICP concentrations in the blood. This microchip system holds promise as a model diagnostic platform that is readily adaptable to hands-free operation.