Rapid diagnosis of mycobacterium tuberculosis with electrical impedance spectroscopy in suspensions using interdigitated microelectrode
| Autor: | S. H. Ettefagh Far, Ahmadreza Bahrmand, AR Hadizadeh Tasbiti, A. R. Pourmir, Sh Yari |
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| Rok vydání: | 2016 |
| Předmět: |
Detection limit
biology 010405 organic chemistry Chemistry General Chemical Engineering Analytical chemistry 02 engineering and technology 021001 nanoscience & nanotechnology biology.organism_classification 01 natural sciences 0104 chemical sciences Analytical Chemistry Suspension (chemistry) Mycobacterium tuberculosis Cell wall Microelectrode Linear relationship 0210 nano-technology Electrical impedance spectroscopy Electrical impedance |
| Zdroj: | Journal of Analytical Chemistry. 71:676-684 |
| ISSN: | 1608-3199 1061-9348 |
| Popis: | A Mycobacterium tuberculosis (MTB) bacilli are still widely spreading and have to be diagnosed fast and efficiently. Therefore, a new simple and rapid method was proposed to detect MTB by the impedance properties of MTB suspensions using interdigitated microelectrodes. As a result, MTB suspensions in deionized (DI) water with different cell concentrations generated different electrical impedance spectral responses. Whereas MTB suspensions in 0.9 wt. % NaCl solution did not produce any significant differences in the impedance spectra in response to different cell concentrations. In DI water suspensions, the impedance at 1 kHz decreased with increasing cell concentrations. The impedance of MTB suspension in DI water has been discussed; it was found to be resulted from the cell wall charges and release of ions from the cells. There was a linear relationship between the impedance and logarithmic value of the cell concentration in the cell concentration range of 102 to 108 cfu/mL, which can be expressed by the regression equation of Z (kΩ) =–456lnN (cfu/mL) + 9717 with R 2 = 0.99. Detection limit was calculated as 104 cfu/mL, which is comparable with many label-free immunosensors for detecting pathogenic bacteria reported in the literature. This work demonstrated that MTB concentration can be determined through measuring the impedance of MTB suspensions in DI water. This new detection mechanism can be an alternative for current impedance methods available for detecting bacterial cells. |
| Databáze: | OpenAIRE |
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