Localized surface plasmon resonance biosensor integrated with microfluidic chip

Abstract

A sensitive and low-cost microfluidic integrated biosensor is developed based on the localized surface plasmon resonance (LSPR) properties of gold nanoparticles, which allows label-free monitoring of biomolecular interactions in real-time. A novel quadrant detection scheme is introduced which continuously measures the change of the light transmitted through the nanoparticle-coated sensor surface. Using a green light emitting diode (LED) as a light source in combination with the quadrant detection scheme, a resolution of 10(-4) in refractive index units (RIU) is determined. This performance is comparable to conventional LSPR-based biosensors. The biological sensing is demonstrated using an antigen/antibody (biotin/anti-biotin) system with an optimized gold nanoparticle film. The immobilization of biotin on a thiol-based self-assembled monolayer (SAM) and the subsequent affinity binding of anti-biotin are quantitatively detected by the microfluidic integrated biosensor and a detection limit of 270 ng/mL of anti-biotin was achieved. The microfluidic chip is capable of transporting a precise amount of biological samples to the detection areas to achieve highly sensitive and specific biosensing with decreased reaction time and less reagent consumption. The obtained results are compared with those measured by a surface plasmon resonance (SPR)-based Biacore system for the same binding event. This study demonstrates the feasibility of the integration of LSPR-based biosensing with microfluidic technologies, resulting in a low-cost and portable biosensor candidate compared to the larger and more expensive commercial instruments.

Advances in Plasmonic Technologies for Point of Care Applications

“…(C) Atomic force microscopy (AFM) and transmission electron microscopy (TEM) images of the nanoparticles on the chip. Reprinted with permission from ref (191). Copyright 2009 Springer.…”

Microfluidic approaches for isolation, detection, and characterization of extracellular vesicles: Current status and future directions

“…Optical detection techniques have been efficiently implemented on-chip, where they are used as a microfluidic biosensor formatted for online fluorescence (Ryu 2011), chemiluminescence (Guan 2015), surface plasmon resonance (SPR) based measurements (Luo 2008, Huang 2009) and surface enhanced Raman spectroscopy (SERS) based optical sensing (Qian 2008). Instead, other parts such as microscopes, spectrophotometers, charge-coupled devices (CCDs) and photomultiplier tubes (PMTs) have yet to be fully integrated to microfluidic devices, for now remaining off-chip because of difficulties in miniaturization (Schwarz 2001, Huang 2005, Myers 2008, Wolter 2008, Lee 2009, Huh 2009).…”

Gold Nano-Island Platform for the Microfluidic Plasmonic Detection of Exosomes

“…A shift towards the longer wavelength of the local LSPR band is noticed upon the binding of bio-molecules onto the metal nanoparticles immobilized on a substrate. While a great number of publications exist on the LSPR phenomenon and its applications, there are only a few trying to integrate LSPR biosensors and microfluidics [3][4]. Recently microfluidics-based designs have been developed and implemented by several researchers in order to isolate and quantify biomolecules which are bio markers for the early diagnosis of cancer.…”