Formation of anisotropic nanoparticle structure for nanoplasmonic biosensing

A novel anisotropic nanoparticle structure consisting of a single gold nanorod and nanospheres is designed. The optical properties, especially the scattering under polarized light, are studied. The signal readout is conducted using dark-field microimaging techniques in a microfluidic chip. The formation of this novel structure is induced by the intermediate biomolecules. Therefore, it demonstrates potential applications in the ultrasensitive detection of biomarkers. As an example, the detection of vascular endothelial growth factor (VEGF165) is demonstrated, and the specificity is also investigated. This unique approach not only effectively reduces background interference but also provides a new approach for accurate sensing of targeted tumor markers.