Abstract
To achieve a functional surface design on the electrode of a light addressable potentiometric sensor (LAPS), two different surface modification techniques were adopted to determine the effect of surface functional groups on the sensitivity and reliability of the LAPS. One was chemisorption of alkanethiols (HS-(CH2)n-X, n is 2 or 11, X is CH3, COOH or NH2) on a gold-deposited electrode, and the other was photochemical immobilization of copolymers containing benzophenone and functional groups of CON(CH3)2, COOH and N(CH3)2 in their side chains on a propyltrimethoxysilane-treated electrode. Linearity was observed between the potentials of inflection points on photocurrent-potential curves (Vpip) and the pH of the contacting solution: Vpip = a - b · pH. Gold deposition on the electrode reduced both the pH sensitivity of the Vpip and the degree of linearity of relationship between Vpip and pH. The alkanethiol chemisorption on the gold surface hardly changed the Vpip-pH relationship irrespective of the terminal functional groups of the alkanethiols, Neither the propyltrimethoxysilane treatment nor the photogel immobilizations changed the pH sensitivities of the Vpip or the linearities between Vpip and at pH 3-8. In conclusion, gold deposition is not suitable for modification of the LAPS electrode, while surface modification with photogel immobilization of a propyltrimethoxysilane-treated electrode can be used without reducing the pH sensitivity or reliability.
| Original language | English |
|---|---|
| Pages (from-to) | 131-139 |
| Number of pages | 9 |
| Journal | Materials Science and Engineering C |
| Volume | 5 |
| Issue number | 2 C |
| Publication status | Published - 1997 Dec |
| Externally published | Yes |
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Keywords
- Alkanethiol
- Benzophenone
- Light addressable potentiometric sensor (LAPS)
- pH
- Photoreactive copolymer
- Self-assembled monolayer
ASJC Scopus subject areas
- Biomaterials
Cite this
Surface modifications of functional electrodes of a light addressable potentiometric sensor (LAPS) : Non-dependency of pH sensitivity on the surface functional group. / Yoshimi, Yasuo; Matsuda, Takehisa; Itoh, Yoshitaka; Ogata, Fukashi; Katsube, Teruaki.
In: Materials Science and Engineering C, Vol. 5, No. 2 C, 12.1997, p. 131-139.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Surface modifications of functional electrodes of a light addressable potentiometric sensor (LAPS)
T2 - Non-dependency of pH sensitivity on the surface functional group
AU - Yoshimi, Yasuo
AU - Matsuda, Takehisa
AU - Itoh, Yoshitaka
AU - Ogata, Fukashi
AU - Katsube, Teruaki
PY - 1997/12
Y1 - 1997/12
N2 - To achieve a functional surface design on the electrode of a light addressable potentiometric sensor (LAPS), two different surface modification techniques were adopted to determine the effect of surface functional groups on the sensitivity and reliability of the LAPS. One was chemisorption of alkanethiols (HS-(CH2)n-X, n is 2 or 11, X is CH3, COOH or NH2) on a gold-deposited electrode, and the other was photochemical immobilization of copolymers containing benzophenone and functional groups of CON(CH3)2, COOH and N(CH3)2 in their side chains on a propyltrimethoxysilane-treated electrode. Linearity was observed between the potentials of inflection points on photocurrent-potential curves (Vpip) and the pH of the contacting solution: Vpip = a - b · pH. Gold deposition on the electrode reduced both the pH sensitivity of the Vpip and the degree of linearity of relationship between Vpip and pH. The alkanethiol chemisorption on the gold surface hardly changed the Vpip-pH relationship irrespective of the terminal functional groups of the alkanethiols, Neither the propyltrimethoxysilane treatment nor the photogel immobilizations changed the pH sensitivities of the Vpip or the linearities between Vpip and at pH 3-8. In conclusion, gold deposition is not suitable for modification of the LAPS electrode, while surface modification with photogel immobilization of a propyltrimethoxysilane-treated electrode can be used without reducing the pH sensitivity or reliability.
AB - To achieve a functional surface design on the electrode of a light addressable potentiometric sensor (LAPS), two different surface modification techniques were adopted to determine the effect of surface functional groups on the sensitivity and reliability of the LAPS. One was chemisorption of alkanethiols (HS-(CH2)n-X, n is 2 or 11, X is CH3, COOH or NH2) on a gold-deposited electrode, and the other was photochemical immobilization of copolymers containing benzophenone and functional groups of CON(CH3)2, COOH and N(CH3)2 in their side chains on a propyltrimethoxysilane-treated electrode. Linearity was observed between the potentials of inflection points on photocurrent-potential curves (Vpip) and the pH of the contacting solution: Vpip = a - b · pH. Gold deposition on the electrode reduced both the pH sensitivity of the Vpip and the degree of linearity of relationship between Vpip and pH. The alkanethiol chemisorption on the gold surface hardly changed the Vpip-pH relationship irrespective of the terminal functional groups of the alkanethiols, Neither the propyltrimethoxysilane treatment nor the photogel immobilizations changed the pH sensitivities of the Vpip or the linearities between Vpip and at pH 3-8. In conclusion, gold deposition is not suitable for modification of the LAPS electrode, while surface modification with photogel immobilization of a propyltrimethoxysilane-treated electrode can be used without reducing the pH sensitivity or reliability.
KW - Alkanethiol
KW - Benzophenone
KW - Light addressable potentiometric sensor (LAPS)
KW - pH
KW - Photoreactive copolymer
KW - Self-assembled monolayer
UR - http://www.scopus.com/inward/record.url?scp=0041633361&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0041633361&partnerID=8YFLogxK
M3 - Article
VL - 5
SP - 131
EP - 139
JO - Materials Science and Engineering C
JF - Materials Science and Engineering C
SN - 0928-4931
IS - 2 C
ER -