Construction of simultaneous SPR and QCM sensing platform.
To construct a novel simultaneous SPR and QCM sensing system, an AT-cut quartz crystal is fabricated by sputtering 250 nm of ITO on one side of the quartz plate over a 5-nm thick underlay of titanium, while a 50-nm thick layer of gold is sputter-deposited on the other side to induce a total light reflection of an incident laser beam on the thin gold layer. The signals of the sensing system are detected using a Handy-SPR and QCA922 when dropping 200 microL of Milli-Q water into the sensing cell. A decrease in the SPR reflected light intensity is clearly identified. In the same experiment, the changes in the resonant frequency and resistance are about 2 kHz and 200 Omega, respectively. Furthermore, the oscillation stabilities of the resonant frequency and resistance are about 50 Hz and 2 Omega, respectively, which are sufficient to detect a large mass change on the QCM/SPR chip.
Kim
Jongmin
J
Department of Chemical Engineering, Dong-A University, 840 Hadan-Dong, Saha-Gu, Pusan 604-714, Korea.
Kim
Seonghoon
S
Ohashi
Tatsuya
T
Muramatsu
Hiroshi
H
Chang
Sang-Mok
SM
Kim
Woo-Sik
WS
D017097:Electric Impedance; D006046:Gold; D007834:Lasers; D011791:Quartz; D014025:Titanium
D011791:Quartz; D006046:Gold; D014025:Titanium