Lee Shinyoung, Eom Seok Chan, Chang Jee Soo, Huh Chul, Sung Gun Yong, Shin Jung H
Department of Physics, KAIST 373-1 Guseong-dong, Yuseong-Gu, Daejeon, Korea.
Opt Express. 2010 Sep 27;18(20):20638-44. doi: 10.1364/OE.18.020638.
We demonstrate label-free optical biosensing using a horizontal air-slotted silicon-rich silicon nitride (SiNx) microdisk resonator. Due to the strong confinement of light in the air-slot, a large resonance shift of 6.2 nm is observed upon reaction of the biotin-functionalized disk with a streptavidin solution with concentration of 2.5 μg/ml. Assuming a linear relationship between resonance shift and streptavidin concentration, we estimate the sensitivity to be 2.5 ± 0.2 nm/(μg/ml). Comparing this value with surface sensitivity of 5.7 nm/nm calculated using FDTD simulations, a detection limit of 30 ± 2 ng/ml, is extrapolated.
我们展示了使用水平空气狭缝富硅氮化硅（SiNx）微盘谐振器的无标记光学生物传感。由于光在空气狭缝中的强烈限制，当生物素功能化盘与浓度为2.5μg/ml的链霉亲和素溶液反应时，观察到6.2nm的大共振位移。假设共振位移与链霉亲和素浓度之间存在线性关系，我们估计灵敏度为2.5±0.2nm/（μg/ml）。将该值与使用FDTD模拟计算的5.7nm/nm的表面灵敏度进行比较，推断出检测限为30±2ng/ml。
