posted on 2013-10-01, 00:00authored byMing Li, Xiang Wu, Liying Liu, Xudong Fan, Lei Xu
The
noise-suppression techniques of label-free optical ring resonator
sensors are crucial to improve their practical sensing capabilities
for biochemical analysis and detection in extremely small detection
concentration. We have developed a self-referencing optofluidic ring
resonator (SR-OFRR) to vastly improve its sensing capability as a
label-free optical biosensor. By monitoring the mode-splitting separation
generated on a coupled ring resonator system, the common-mode noise
is suppressed by 2 orders of magnitude without any external noise-suppression
techniques. In this work, we first carried out theoretical analysis
to elucidate the sensing principle and then applied the SR-OFRR biosensor
to experimentally detect bovine serum albumin with a concentration
detection limit on the order of 1 pg/mL (∼15 fM).