2
|
Cheng X, Liu YS, Irimia D, Demirci U, Yang L, Zamir L, Rodríguez WR, Toner M, Bashir R. Cell detection and counting through cell lysate impedance spectroscopy in microfluidic devices. LAB ON A CHIP 2007; 7:746-55. [PMID: 17538717 PMCID: PMC4476634 DOI: 10.1039/b705082h] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Cell-based microfluidic devices have attracted interest for a wide range of applications. While optical cell counting and flow cytometry-type devices have been reported extensively, sensitive and efficient non-optical methods to detect and quantify cells attached over large surface areas within microdevices are generally lacking. We describe an electrical method for counting cells based on the measurement of changes in conductivity of the surrounding medium due to ions released from surface-immobilized cells within a microfluidic channel. Immobilized cells are lysed using a low conductivity, hypotonic media and the resulting change in impedance is measured using surface patterned electrodes to detect and quantify the number of cells. We found that the bulk solution conductance increases linearly with the number of isolated cells contributing to solution ion concentration. The method of cell lysate impedance spectroscopy is sensitive enough to detect 20 cells microL(-1), and offers a simple and efficient method for detecting and enumerating cells within microfluidic devices for many applications including measurement of CD4 cell counts in HIV patients in resource-limited settings. To our knowledge, this is the most sensitive approach using non-optical setups to enumerate immobilized cells. The microfluidic device, capable of isolating specific cell types from a complex bio-fluidic and quantifying cell number, can serve as a single use cartridge for a hand-held instrument to provide simple, fast and affordable cell counting in point-of-care settings.
Collapse
Affiliation(s)
- Xuanhong Cheng
- BioMEMS Resource Center and Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA
| | - Yi-shao Liu
- Birck Nanotechnology Center, School of Electrical Engineering and Computer Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Daniel Irimia
- BioMEMS Resource Center and Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA
| | - Utkan Demirci
- BioMEMS Resource Center and Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA
| | - Liju Yang
- Birck Nanotechnology Center, School of Electrical Engineering and Computer Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
- Now at Biomanufacturing Research Institute & Technology Enterprise (BRITE), Department of Chemistry, North Carolina Central University, Durham, NC 27707, USA
| | - Lee Zamir
- Partners AIDS Research Center, Massachusetts General Hospital, 02114, USA
- Division of AIDS, Harvard Medical School, and Brigham and Women's Hospital, Boston, Massachusetts, 02115, USA
| | - William R. Rodríguez
- Partners AIDS Research Center, Massachusetts General Hospital, 02114, USA
- Division of AIDS, Harvard Medical School, and Brigham and Women's Hospital, Boston, Massachusetts, 02115, USA
- ; Fax: +1-617-724-2999; Tel: +1-617-371-4876; ; Fax: +1-765-494-6441; Tel: +1-765-496-6229; .; Fax: +1-617-726-4691; Tel: +1-617-726-8099
| | - Mehmet Toner
- BioMEMS Resource Center and Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA
- ; Fax: +1-617-724-2999; Tel: +1-617-371-4876; ; Fax: +1-765-494-6441; Tel: +1-765-496-6229; .; Fax: +1-617-726-4691; Tel: +1-617-726-8099
| | - Rashid Bashir
- Birck Nanotechnology Center, School of Electrical Engineering and Computer Engineering, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
- ; Fax: +1-617-724-2999; Tel: +1-617-371-4876; ; Fax: +1-765-494-6441; Tel: +1-765-496-6229; .; Fax: +1-617-726-4691; Tel: +1-617-726-8099
| |
Collapse
|