Dark‐field hyperspectral imaging for label free detection of nano‐bio‐materials

Abstract

Nanomaterials are playing an increasingly important role in cancer diagnosis and treatment. Nanoparticle (NP)‐based technologies have been utilized for targeted drug delivery during chemotherapies, photodynamic therapy, and immunotherapy. Another active area of research is the toxicity studies of these nanomaterials to understand the cellular uptake and transport of these materials in cells, tissues, and environment. Traditional techniques such as transmission electron microscopy, and mass spectrometry to analyze NP‐based cellular transport or toxicity effect are expensive, require extensive sample preparation, and are low‐throughput. Dark‐field hyperspectral imaging (DF‐HSI), an integration of spectroscopy and microscopy/imaging, provides the ability to investigate cellular transport of these NPs and to quantify the distribution of them within bio‐materials. DF‐HSI also offers versatility in non‐invasively monitoring microorganisms, single cell, and proteins. DF‐HSI is a low‐cost, label‐free technique that is minimally invasive and is a viable choice for obtaining high‐throughput quantitative molecular analyses. Multimodal imaging modalities such as Fourier transform infrared and Raman spectroscopy are also being integrated with HSI systems to enable chemical imaging of the samples. HSI technology is being applied in surgeries to obtain molecular information about the tissues in real‐time. This article provides brief overview of fundamental principles of DF‐HSI and its application for nanomaterials, protein‐detection, single‐cell analysis, microbiology, surgical procedures along with technical challenges and future integrative approach with other imaging and measurement modalities. This article is categorized under: Diagnostic Tools > in vitro Nanoparticle‐Based Sensing Diagnostic Tools > in vivo Nanodiagnostics and Imaging Implantable Materials and Surgical Technologies > Nanoscale Tools and Techniques in Surgery

Rosmarinic Acid-Loaded Polymeric Nanoparticles Prepared by Low-Energy Nano-Emulsion Templating: Formulation, Biophysical Characterization, and In Vitro Studies

“…TEM microscopy images of our RA-loaded polymeric NPs revealed the spherical shape and showed similar diameter sizes as those obtained from DLS measurements (Figure 1A). Additionally, a dark-field image at 100× magnification and a dark-field hyperspectral image [52] of RA-loaded PLGA NPs were used to confirm the presence of RA entrapped in PLGA NPs (Figure 1B,C). For that purpose, the scattering spectra from the dark-field image of each component (e.g., RA and PLGA) were separately obtained (Figure S4) allowing the spectral image of RA-loaded PLGA NPs to be mapped (Figure 1D).…”

Short-Wavelength Infrared Hyperspectral Imaging for Biomedical Applications

“…This idea of combining high spectral resolution with imaging can be further combined with almost any other imaging technique and measurement geometry, including wide-field imaging of larger objects and endoscopic imaging. 1,[15][16][17][18][19][20] As a result, HSI has recently been explored for a variety of medical applications and is slowly becoming a part of the standard biomedical toolbox.…”

“…Currently, HSI is more frequently incorporated as an additional feature to other imaging techniques-such as spatial frequency domain imaging (SFDI), coherent anti-Stokes Raman scattering (CARS) microscopy, and optical coherence tomography (OCT). 15,[26][27][28][29][30][31][32][33] Despite the trend of combining HSI with other imaging modalities, the available literature has not focused on SWIR optical imaging as such. Instead, HSI is associated with medical applications in general 1 or specific applications 5,21 such as cancer diagnostics.…”

Spatially Resolved Spectroscopic Characterization of Nanostructured Films by Hyperspectral Dark-Field Microscopy

“…Hyperspectral dark-field microscope (HSDFM) is a newly emerging multifunctional analytical tool that can simultaneously perform high-resolution single-wavelength imaging and high-resolution single-pixel spectroscopy for nanostructured metallic and dielectric films as well as biosamples. , According to the recently published papers on HSDFM, − its typical applications include monitoring the morphological evolution of nanoparticles in different biological environments, studying the cellular uptake of different nanoparticles, , detection of the targeted nanoparticles to cancer cells . Particularly, Tseng and El-Khoury research groups investigated the plasmonic characteristics of a single noble metal nanoparticle using the hyperspectral imaging system combined with a dark-field microscope and Fourier transform spectrometry. , Wonner et al studied the electrochemical oxidation and dissolution process of individual silver nanoparticles based on the electrochemical method and the HSDFM purchased from CytoViva Inc .…”