원문정보
초록
영어
In this presentation, we report a quick and reproducible surface-enhanced Raman scattering
(SERS)-based immunoassay technique, using hollow gold nanospheres (HGNs) and magnetic
beads. HGNs show strong SERS enhancement effects from individual particles because hot spots
can be localized within pinholes in the hollow particle structure. Accordingly, HGNs can be used for highly reproducible immunoanalysis of cancer markers. Magnetic beads were used as supporting substrates for the formation of the immunocomplex. In addition, we have implemented this SERS-based immunoassay, performed in a microtube, into a microfluidic platform. The SERSbased optofluidic sensor is composed of three compartments consisting of the gradient channel that serially dilutes the target marker, the injection and mixing area of antibody-conjugated hollow gold nanospheres and magnetic beads and the trapping area of sandwich immunocomplexes using multiple solenoids. Quantitative analysis of a specific target marker is performed by analyzing its characteristic SERS signals. For validation, a well-known lung cancer marker, carcinoembryonic antigen (CEA), was used as a target. Based on experimental results, the limit of detection (LOD) was determined to be 1–10 pg/mL, this value being about 100–1000 times more sensitive than the LOD of conventional enzyme-linked immunosorbent assay (ELISA). Our proposed SERS-based optofluidic sensing technology has many advantages over previously reported SERS detection methods, such as good reproducibility, low limits of detection and fast assay times. Accordingly, this technique is expected to be a powerful clinical tool for fast and reliable cancer diagnosis.