Caractérisation électrochimique de matériaux d'électrodes d'un dispositif capteur pour le diagnostic clinique du dysfonctionnement sudomoteur

Abstract : SUDOSCAN TM is a new technology, conceived by the company " Impeto Medical ", for the analysis of sudomotor functions, allowing to realize an early diagnosis of diabetes. This non invasive device is based on measurements of skin conductance via the application of low voltage potentials between nickel electrodes, placed on different skin regions, and measuring low generated currents. The sensitivity of this technology is attributed to the sensitivity of electrodes to sweat composition. In this context and to support this hypothesis, an in-depth study of the electrochemical behavior of nickel was carried out in sweat-mimic solutions and using a set-up similar to that of the medical device. This study allowed us to define the origin of the measured currents by SUDOSCANTM. This study also clearly indicates that the nature of electrodes and the composition of sweat in chloride are the two key parameters allowing the sensitivity of nickel. This led us to study the influence of chloride concentrations on the kinetic of the electrochemical reactions. The proposed mechanisms and the obtained kinetic parameters were then used by " Impeto Medical " to complete a theoretical model of the obtained electrical signals during the clinical tests. An evaluation of the ageing of electrodes on their performance was conducted by realizing a surface analyzes using XPS and SIMS spectroscopies. Our results have highlighted the importance of alternating the polarity of electrodes to ensure their sensitivity and the reproducibility of measurements. However, after frequent uses, the metal/sweat interaction can lead to a slight deterioration of the electrodes surface. Finally, in order to reduce the allergic risk, the electrochemical studies were extended to the stainless steel 304L as a replacement material of nickel. The electrochemical study shows that stainless steel 304L is sensitive to the deviation of sweat ionic balance. This makes stainless steel 304L a substitution material very promising.
Document type :
Theses
Complete list of metadatas

Cited literature [97 references]  Display  Hide  Download

https://pastel.archives-ouvertes.fr/pastel-00700902
Contributor : Adrien Orengo <>
Submitted on : Thursday, May 24, 2012 - 11:29:58 AM
Last modification on : Thursday, April 11, 2019 - 4:02:22 PM
Long-term archiving on : Saturday, August 25, 2012 - 2:26:52 AM

Identifiers

  • HAL Id : pastel-00700902, version 1

Citation

Hanna Ayoub. Caractérisation électrochimique de matériaux d'électrodes d'un dispositif capteur pour le diagnostic clinique du dysfonctionnement sudomoteur. Autre. Université Pierre et Marie Curie - Paris VI, 2011. Français. ⟨pastel-00700902⟩

Share

Metrics

Record views

5571

Files downloads

15352