P1.9.20 New chemical sensor for detergents determination
- 14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
- P1.9 Technology and Application
- A. Bratov, N. Abramova, A. Ipatov, A. Merlos - Instituto de Microelectronica de Barcelona, Centro Nacional de Microelectronica (CSIC) (Spain)
- 1220 - 1222
A new impedimetric sensor based on an interdigitated electrode array with electrode digits located at the bottom of microcapillaries formed in silicon dioxide is proposed. Microcapillaries are opened at the top, so that in contact with an electrolyte solution the ac current flows close to the surface of the capillary wall from one electrode to another and is significantly affected by changes in surface conductance at the SiO2/electrolyte interface. Adsorption of detergents on the sensor surface affects the charge distribution in the electrical double layer that is registered as a change in the surface conductance. The sensor may be used to measure a detergent residues starting from 5 ppm even in solutions with high electrolyte conductivity.