Volatile organic compound specific detection by electrochemical signals using a cell-based sensor.
A cell-based in vitro exposure system was developed to determine whether oxidative stress plays a role in the cytotoxic effects of volatile organic compounds (VOCs) such as benzene, toluene, xylene, and chlorobenzene, using human epithelial HeLa cells. Thin films based on cysteine-terminated synthetic oligopeptides were fabricated for immobilization of the HeLa cells on a gold (Au) substrate. In addition, an immobilized cell-based sensor was applied to the electrochemical detection of the VOCs. Layer formation and immobilization of the cells were investigated with surface plasmon resonance (SPR), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The adhered living cells were exposed to VOCs; this caused a change in the SPR angle and the VOC-specific electrochemical signal. In addition, VOC toxicity was found to correlate with the degree of nitric oxide (NO) generation and EIS. The primary reason for the marked increase in impedance was the change of aqueous electrolyte composition as a result of cell responses. The p53 and NF-kappaB downregulation were closely related to the magnitude of growth inhibition associated with increasing concentrations of each VOC. Therefore, the proposed cell immobilization method, using a self-assembly technique and VOC-specific electrochemical signals, can be applied to construct a cell microarray for onsite VOC monitoring.
Chung
Sang Gwi
SG
Department of Environmental Engineering, KunKuk University, Seoul, Korea.
Kim
Jo Chun
JC
Park
Chong-Ho
CH
Ahn
Woong-Shick
WS
Kim
Yong-Wan
YW
Choi
Jeong-Woo
JW
D015374:Biosensing Techniques / Q000379:methods*; D018914:Cells, Immobilized; D017097:Electric Impedance; D004563:Electrochemistry / Q000379:methods*; D006367:HeLa Cells; D006801:Humans; D006841:Hydrocarbons, Aromatic / Q000032:analysis / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects*; D013057:Spectrum Analysis; D020349:Surface Plasmon Resonance; D018675:Toxicity Tests / Q000379:methods*; D014835:Volatilization
D006841:Hydrocarbons, Aromatic