Analytical Sciences

Abstract − Analytical Sciences, 32(3), 307 (2016).

Dark Field Microscopic Sensitive Detection of Amyloid Fibrils Using Gold Nanoparticles Modified with Antibody
Tong BU,*,** Tamotsu ZAKO,** and Mizuo MAEDA*,**
*Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
**Bioengineering Laboratory, RIKEN Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
Dark field microscopy (DFM) was employed to detect amyloid β (Aβ) fibrils-induced gold nanoparticle (AuNP) aggregation at the single-particle level, with a detection limit of 40 pM fibrils. The sensitivity of this method is higher than that of the current fibril-specific detection method using probe dye, such as thioflavin T, for which sub-μM level of fibrils are necessary. This study further proved the potential application of DFM in the analytical methods based on AuNP aggregation.