Single-drop analysis of various proteases in a cancer cell lysate using a capillary-assembled microchip

Anal Bioanal Chem. 2008 Aug;391(7):2507-12. doi: 10.1007/s00216-008-2105-x. Epub 2008 Apr 23.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibiotics, Antineoplastic / pharmacology
  • Caspases / analysis
  • Caspases / metabolism
  • Doxorubicin / pharmacology
  • Female
  • HeLa Cells
  • Humans
  • Isoenzymes
  • Microfluidic Analytical Techniques / instrumentation
  • Microfluidic Analytical Techniques / methods*
  • Peptide Hydrolases / analysis*
  • Peptide Hydrolases / metabolism
  • Protein Array Analysis / instrumentation
  • Protein Array Analysis / methods
  • Uterine Cervical Neoplasms / drug therapy
  • Uterine Cervical Neoplasms / enzymology*

Substances

  • Antibiotics, Antineoplastic
  • Isoenzymes
  • Doxorubicin
  • Peptide Hydrolases
  • Caspases