title: Single-drop analysis of various proteases in a cancer cell lysate using a capillary-assembled microchip.
abstract: Single-drop analysis of two different real sample solutions (2 microL) while simultaneously monitoring the activity of two sets of ten different proteases on a single microfluidic device is presented. The device, called a capillary-assembled microchip (CAs-CHIP), is fabricated by embedding square glass sensing capillaries (reagent-release capillaries, RRC) in the polydimethylsiloxane (PDMS) lattice microchannel, and used for that purpose. First, the performance reliability was evaluated by measuring the fluorescence response of twenty caspase-3-sensing capillaries on a single CAs-CHIP, and a relative standard deviation of 1.5-8.2 (% RSD, n = 5 or 10) was obtained. This suggests that precise multiplexed protease-activity sensing is possible by using a single CAs-CHIP with multiple RRCs embedded. Then, using a single CAs-CHIP, real sample analysis of the activity of ten different caspases/proteases in cervical cancer (HeLa) cell lysate treated and untreated with the cell-death-inducer drug, doxorubicin, was simultaneously carried out, and a significant difference in enzyme activity between these two samples was observed. These results suggested the usefulness of the CAs-CHIP in the field of drug discovery.
authors.affiliation: Graduate School of Material Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo, 678-1297, Japan.
authors.forename: Terence G
authors.initials: TG
authors.lastname: Henares
authors.forename: Fumio
authors.initials: F
authors.lastname: Mizutani
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Sekizawa
authors.forename: Hideaki
authors.initials: H
authors.lastname: Hisamoto
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D020169:Caspases / Q000032:analysis / Q000378:metabolism; D004317:Doxorubicin / Q000494:pharmacology; D005260:Female; D006367:HeLa Cells; D006801:Humans; D007527:Isoenzymes; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D010447:Peptide Hydrolases / Q000032:analysis* / Q000378:metabolism; D040081:Protein Array Analysis / Q000295:instrumentation / Q000379:methods; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy / Q000201:enzymology*
chemical_list: D000903:Antibiotics, Antineoplastic; D007527:Isoenzymes; D004317:Doxorubicin; D010447:Peptide Hydrolases; D020169:Caspases