An electrical biosensor for the detection of circulating tumor cells.
In this report, we demonstrate a semi-integrated electrical biosensor for the detection of rare circulating tumor cells (CTCs) in blood. The sample was first enriched through a combination of immunomagnetic isolation and size filtration. The integration of both methods provided a high enrichment performance with a recovery rate above 70%, even for very low numbers of cancer cells present in the original sample (10 spiked MCF7 cells in 0.5 mL of blood). In the same system, the sample was then transferred to a microchip for further magnetic concentration, followed by immunochemical trapping and electronic detection by impedance spectroscopy. Three levels of spiked CTC number (30±2, 124±29, 273±23) in 10 μL of filtered blood sample were distinguished by monitoring the impedance change of the microelectrode array (MEA). The integration of different functions in a single system provided a methodology to process milliliter-sized blood samples at the macroscale and interface with the microdimensions of a highly sensitive electronic detector. The results showed that the whole system was able to detect different levels of spiked cancer cells without the use of time- and cost-intensive fluorescence labeling and image analysis. This has the potential to provide clinicians with a standalone system to monitor changes in CTC numbers throughout therapy conveniently and frequently for efficient cancer treatments.
Institute of Microelectronics, Agency for Science, Technology and Research, 11 Science Park Road, Singapore Science Park II, Singapore 117685, Singapore. ykchung@ms.mainz
Yao-Kuang
YK
Chung
Julien
J
Reboud
Kok Chuan
KC
Lee
Hui Min
HM
Lim
Pei Yi
PY
Lim
Karen Yanping
KY
Wang
Kum Cheong
KC
Tang
HongMiao
H
Ji
Yu
Y
Chen
D015374:Biosensing Techniques / Q000295:instrumentation*; D001943:Breast Neoplasms / Q000097:blood* / Q000503:physiopathology*; D045744:Cell Line, Tumor; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D009360:Neoplastic Cells, Circulating