title: Real-time concentration monitoring in microfluidic system via plasmonic nanocrescent arrays.
abstract: In this work, on-chip bio/chemical sensor was reported based on localized surface plasmon resonance of nanocrescent patterns fabricated via electron beam lithography. The nanocrescent arrays with different dimensional features exhibited controllable plasmonic properties in accordance with the simulation results based on the finite-difference time-domain model. The highest refractive index sensitivity of the fabricated samples was achieved to be ~699.2 nm/RIU with a figure of merit of ~3.1 when the two opposite crescents own a gap of ~43.3 nm. Such obtained plasmonic sensor was further integrated into the microfluidic system which can simply control the specific analyte concentrations via tuning the flow rate ratios between two injecting microstreams. Our method has successfully demonstrated the capability of the nanocrescent patterns as on-chip plasmonic bio/chemical sensor for real-time monitoring of dynamic concentrations in the microchannel.
authors.affiliation: Nano Science and Technology Program and KAUST-HKUST Micro/Nanofluidic Joint Laboratory, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Bingpu
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Xiao
authors.initials: X
authors.lastname: Xiao
authors.affiliation: Soft Matter and Interdisciplinary Research Institute, College of Physics, Chongqing University, Chongqing 400044, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.affiliation: Environmental Science Programs, School of Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Yibo
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Soft Matter and Interdisciplinary Research Institute, College of Physics, Chongqing University, Chongqing 400044, China.
authors.forename: Yingzhou
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Nano Science and Technology Program and KAUST-HKUST Micro/Nanofluidic Joint Laboratory, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong. Electronic address: phwen@ust.hk.
authors.forename: Weijia
authors.initials: W
authors.lastname: Wen
mesh_terms: D001704:Biopolymers / Q000032:analysis*; D003199:Computer Systems; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017022:Flow Injection Analysis / Q000295:instrumentation*; D006046:Gold / Q000737:chemistry*; D056656:Lab-On-A-Chip Devices; D053768:Metal Nanoparticles / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D001704:Biopolymers; D006046:Gold
keywords: Biosensor; Microfluidics; Nanocrescent; Surface plasmon resonance