Hyperspectral surface-enhanced Raman imaging of labeled silver nanoparticles in single cells

We describe the development of an acousto-optic tunable filter (AOTF)-based hyperspectral surface-enhanced Raman imaging (HSERI) system equipped with an intensified charged coupled device and an avalanche photodiode. The AOTF device is a miniature rapid-scanning solid-state device that has no moving parts and can be rapidly tuned (microseconds) either sequentially or randomly, over a wide spectral range between 600 and 900nm [corresponding to a large relative wave number range (∼0–4500cm−1)], with respect to a 632.8nm excitation and can also acquire images at a fairly narrow band of ∼7cm−1. In this article we describe a confocal surface-enhanced Raman imaging (SERI) system developed in our laboratory that combines hyperspectral imaging capabilities with surface-enhanced Raman scattering (SERS) to identify cellular components with high spatial and temporal resolution. The HSERI system’s application to cellular imaging is demonstrated using SERS-labeled nanoparticles in cellular systems.