Impedimetric method for measuring ultra-low E. coli concentrations in human urine.
Biosens Bioelectron
; 66: 244-50, 2015 Apr 15.
Article
em En
| MEDLINE
| ID: mdl-25437359
In this study, we developed an interdigitated gold microelectrode-based impedance sensor to detect Escherichia coli (E. coli) in human urine samples for urinary tract infection (UTI) diagnosis. E. coli growth in human urine samples was successfully monitored during a 12-h culture, and the results showed that the maximum relative changes could be measured at 10Hz. An equivalent electrical circuit model was used for evaluating the variations in impedance characteristics of bacterial growth. The equivalent circuit analysis indicated that the change in impedance values at low frequencies was caused by double layer capacitance due to bacterial attachment and formation of biofilm on electrode surface in urine. A linear relationship between the impedance change and initial E. coli concentration was obtained with the coefficient of determination R(2)>0.90 at various growth times of 1, 3, 5, 7, 9 and 12h in urine. Thus our sensor is capable of detecting a wide range of E. coli concentration, 7×10(0) to 7×10(8) cells/ml, in urine samples with high sensitivity.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Urina
/
Técnicas Biossensoriais
/
Escherichia coli
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Biosens Bioelectron
Assunto da revista:
BIOTECNOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Taiwan
País de publicação:
Reino Unido