Wide-field hyperspectral 3D imaging of functionalized gold nanoparticles targeting cancer cells by reflected light microscopy

Recent years have seen tremendous progress in the development and characterization of noble metallic nanostructures for bio-applications. Since gold plasmonic nanoparticles (AuNPs) are photostable, water soluble and biocompatible in vitro and in vivo, they are widely used as optical biomarkers in biological and biomedical applications for detection of chemical and biological analytes, imaging of cells and tissues, detection and treatment of cancer cells [1]. Determination of NP concentration, spatial three-dimensional (3D) position and distribution as well as analysis of the spectral characteristics of single and aggregated NPs are very important for selective cell detection and treatment in bio-applications [2]. Unfortunately, the small size of AuNPs and the complex biological environment increase the difficulty to visualize AuNPs. The acquisition of complete information about their physical properties with the target cells or tissues requires the development of more sensitive and efficient microscopy approaches. Widely used as labels in biological systems, water-soluble organic fluorophores and, recently,