Nanoparticles for Detection, Diagnostics, and Targeting using Hyperspectral Imaging

Abstract

Novel and modified nanoparticles containing multiple inherent and specific functionalities make them powerful tools in bioimaging, cancer targeting, cancer therapy, and microbial capture and detection.1 For example, gold and iron oxide nanoparticles offer potential advantages in the bioimaging of cancer cells due to their respective strong absorption and scattering, and magnetic properties.2 Several studies in the literature suggest the potency and efficiency of these nanoparticles in therapeutic applications. For example, per Alhalili Z. et al (2016), there was no observed significant decrease (P>0.05) in cell viability when TD47 cells are treated with gold nanoparticles (AuNPs) alone.3 However, the same cells were significantly killed by the application of AuNPs chemically conjugated to Taxol, suggesting the potential of gold nanoparticles for efficient delivery of Taxol to breast cancer cells. Similarly, Ding R.L. (2017) reported the release of endostatin (ES) in a sustained manner in vitro that showed an excellent inhibitory effect on HUVECs proliferation and migration. 4 The study concluded that ES-NPs significantly improved the anticancer activity of ES by affecting angiogenesis. Despite similar developments in nanomaterial research, much remains to be done in terms of the characterization of the interaction between the cells and the drug loaded nanoparticles. In this study, we report the use of CytoViva Hyperspectral Imaging technology to identify cellular uptake of nanoparticles and to attempt to characterize (if any), the interaction between selected NPs and colon cancer cells.The CytoViva's Hyperspectral microscopy technology incorporates patented high signal-to-noise optical microscopy with high spectral resolution hyperspectral imaging (HSI). This enables optical observation and quantitative spectral analysis of nanoscale samples in a wide range of biological and materials-based environments. In addition, the hyperspectral microscopy can be used to confirm unique surface chemistry and functional groups added to nanomaterials. Furthermore, certain biologicals, such as bacteria and pathogens, can be optically observed, spectrally characterized and mapped in tissue and other environments, especially after capturing or marking them with nanoparticles. Importantly, the imaging system does not require any fluorescent markers.In this study, SW480 colon cancer cells (ATCC) were grown in chamber slides and exposed to varying concentrations (10-100 µM) of nanoparticles solutions in different wells. After an overnight exposure, the monolayers were fixed in 4% formalin in PBS and imaged using the CytoViva HSI system. In this preliminary work, we demonstrate the use of HSI to characterize the spectral profile of nanoparticles internalized by or attached to cells. Figures 1A and 1B show an optical image and hyperspectral scan of the SW480 cells, respectively, with no added nanoparticles. Figure 2A depicts the AuNPs inside cells or in circular rings around the cells suggesting surface attachment. The HSI spectra (...