Cl- sensitive biosensor used electrolyte-solution-gate diamond FETs.
We have investigated the electrolyte-solution-gate field effect transisitors (SGFETs) used hydrogen terminated (H-terminated) or partially oxygen terminated (O-terminated) polycrystalline diamond surface in the Cl- and Br- ionic solutions. The H-terminated channel SGFETs are insensitive to pH values in electrolyte solutions. The threshold voltages of the diamond SGFETs shift according to the density of Cl- and Br- ions about 30 mV/decade. One of the attractive biomedical applications for the Cl- sensitive SGFETs is the detection of chloride density in blood or in sweat especially in the case of cystic fibrosis. The sensitivities of Cl- and Br- ions have been lost on the partially O-terminated diamond surface. These phenomena can be explained by the polarity of surface change on the H-terminated and the O-terminated surface.
School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan. song@kaw.comm.waseda.ac.jp
Kwang-Soup
KS
Song
Toshikatsu
T
Sakai
Hirofumi
H
Kanazawa
Yuta
Y
Araki
Hitoshi
H
Umezawa
Minoru
M
Tachiki
Hiroshi
H
Kawarada
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D002713:Chlorine / Q000032:analysis* / Q000737:chemistry*; D018130:Diamond / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods*; D004573:Electrolytes / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014173:Transistors, Electronic
D004573:Electrolytes; D002713:Chlorine; D018130:Diamond