Surface-Enhanced Raman Scattering (SERS) is emerging as a promising strategy for the quantification of immunoglobulin G (IgG) due to its inherent high sensitivity and specificity; however, it remains challenging to integrate SERS detection with a microfluidic system in a simple, efficient and low-cost manner. Here, we report on a novel bifunctional plasmonic-magnetic particle-based immunoassay, in which plasmonic nanoparticles act as soluble SERS immunosubstrates, whereas magnetic particles are for promoting micromixing in a microfluidic chip. With this novel SERS immunosubstrate in conjunction with the unique microfluidic system, we could substantially reduce the assay time from 4 hours to 80 minutes as well as enhance the detection specificity by about 70% in comparison to a non-microfluidic immunoassay. Compared to previous microfluidic SERS systems, our strategy offers a simple microfluidic chip design with only one well for mixing, washing and detection.
Lim Wei Yap,abc Huaying Chen,d Yuan Gao,b Karolina Petkovic,b Yan Liang,a Kae Jye Si,ac Huanting Wang,a Zhiyong Tang,e Yonggang Zhu*bcd and Wenlong Cheng*ac
* Corresponding authors
a Department of Chemical Engineering, Monash University, Clayton, Australia
b CSIRO Manufacturing, Private Bag 10, Clayton South, Australia
c Melbourne Centre for Nanofabrication, 151 Wellington Rd., Clayton, Australia
d Harbin Institute of Technology (Shenzhen), Xili University Town, Shenzhen 518055, China
e CAS Key Lab of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, P. R. China