Femtogram detection of cytokines in a direct dot-blot assay using SERS microspectroscopy and hydrophilically stabilized Au–Ag nanoshells†
Abstract
Rapid parallel detection of two cytokines (IL-6 and IL-8) with femtogram sensitivity in a simple direct dot-blot assay is demonstrated. The microspectroscopic SERS acquisition scheme employs rationally designed, hydrophilically stabilized Au–Ag nanoshells as SERS labels, which are optimized for signal enhancement upon red laser excitation.