The surface-enhanced Raman spectroscopy platform can detect amyloid beta biomarkers at ultra-low concentrations in body fluids, potentially enabling earlier diagnosis and monitoring of disease progression.
The Korea Research Institute of Standards and Science (KRISS) has developed an ultrasensitive diagnostic platform based on surface-enhanced Raman spectroscopy (SERS) that amplifies molecular optical signals by more than 100 million times, enabling precise detection and quantification of trace amounts of Alzheimer’s disease biomarkers in body fluids.
The platform demonstrates sensitivity over 100,000 times greater than conventional enzyme-linked immunosorbent assay (ELISA) methods and can accurately distinguish and quantify multiple biomarkers simultaneously, according to research published in Biosensors & Bioelectronics.
The technology addresses current limitations in Alzheimer’s diagnosis, which relies primarily on expensive imaging modalities like PET and MRI that can cost over $750 per examination and require specialized facilities. These imaging techniques can only detect the disease after significant progression, making early detection difficult.
Novel Gold Nanoparticle Design Improves Signal Uniformity
The research team developed distinct, multi-type gold nanoparticles with a sunflower-shaped cross-section that produce strong and uniform SERS signals from individual particles. This design overcomes signal non-uniformity issues caused by variations in interparticle spacing found in conventional spherical gold nanoparticles.
By creating a high-density, uniform distribution of signal enhancement sites both inside and on the surface of each particle, the nanoparticles generate strong and highly reproducible signals even at the single-particle level. The platform achieves quantitative performance proportional to target molecule concentration while enabling simultaneous detection of multiple distinct targets.
Using multiplex SERS nanoparticles, each assigned a unique optical identification, researchers successfully quantified ultra-trace levels of amyloid beta (Aβ) 42 and Aβ 40 at concentrations as low as 8.7 × 10⁻¹⁷ g/mL and 1.0 × 10⁻¹⁵ g/mL, respectively. The concentrations of these two peptides in body fluids and their ratio (Aβ42/Aβ40) enable early assessment of Alzheimer’s disease progression.
Platform Offers Commercial Potential Beyond Alzheimer’s
“The sensing platform we have developed can be mass-produced at low cost and flexibly adapted to a wide range of biomarkers,” says Dr You Eun-Ah, principal research scientist at the KRISS Medical Metrology Group, in a release. “Beyond Alzheimer’s disease, it holds high versatility and strong commercialization potential for the early and rapid in vitro diagnosis and monitoring of various diseases, including cancers, neurological disorders, and infectious diseases.”
The technology represents what researchers describe as world-leading performance in both sensitivity and dynamic detection range for multiplex quantitative analysis. Current body fluid tests for Alzheimer’s biomarkers have lacked sufficient accuracy to serve as reliable diagnostic tools, creating a gap the new platform aims to fill.
The research was supported by the National Research Council of Science & Technology Research Initiative Program and the Basic Research Program of KRISS.
Photo caption: Dr You Eun-Ah (left), principal research scientist, and Dr Kim Ryeong Myeong (right), senior research scientist at KRISS, analyzing biomarker detection results using multiplexed SERS sensing platform.
Photo credit: Korea Research Institute of Standards and Science (KRISS)
