INTEGRATION OF NEURAMINIDASE INHIBITOR ASSAY INTO SINGLE STEP OPERATION USING COMBINABLE PDMS CAPILLARY (CPC) SENSOR Tadashi Ishimoto, Kaede Jigawa, Terence G. Henares, Tatsuro Endo, Hideaki Hisamoto Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Japan ABSTRACT Neuraminidase inhibitor assay requiring complicated step-by-step operation was successfully integrated into ”Single-Step” by using CPC sensor. We developed a combinable PDMS capillary (CPC) sensor for enzyme inhibition assay using the concave and convex type PDMS substrates. In the conventional enzyme inhibitor assay, complicated analytical procedures, such as mixing and dissolution, are required. In contrast, this sensor allows single-step assay possible only by sample introduction via capillary action. Here, we applied this technique for neuraminidase inhibitor assay as application and found appropriate experimental condition allowing single-step assay of neuraminidase inhibitor. KEYWORDS Capillary array sensor, Combinable PDMS capillary, Neuraminidase inhibitor assay, Single step operation INTRODUCTION Neuraminidase is an enzyme which exists on the surface of an influenza virus. This releases the newly reproduced virus from a host cell and promotes the infection to a surrounding cell (Fig. 1). Fig.1: The principle of infection of influenza virus by neuraminidase For this reason, neuraminidase inhibitor assay is very important for influenza drug development. However, in the conventional assay [1], complicated step-by-step operation is necessary, because optimal pH of the enzyme reaction differs from that of the fluorescence detection. On the other hand, recently, we developed a combinable PDMS capillary (CPC) sensor for enzyme inhibitor assay using the concave and convex type PDMS substrates immobilizing enzyme and fluorescent substrate independently (Fig. 2). Fig. 2: Preparation of CPC sensor Hemagglutinin Neuraminidase Host cell Influenza virus Propagation Inhibition! Emission Soluble PEG coating containing fluorescent substrate Insoluble coating containing enzyme 500 μm 300 μm Combine PDMS 1cm Array 16th International Conference on Miniaturized Systems for Chemistry and Life Sciences October 28 - November 1, 2012, Okinawa, Japan 978-0-9798064-5-2/μTAS 2012/$20©12CBMS-0001 821