Review

Authors: Elliot R McVeigh

This article reviews recent developments in selected imaging technologies focused on the cardiovascular system. The techniques covered are: ultrasound biomicroscopy (UBM), microSPECT, microPET, near infrared imaging, and quantum dots. For each technique, the basic physical principles are explained and recent example applications demonstrated.

Topics: Animals; Blood Flow Velocity; Humans; Infrared Rays; Microcirculation; Neoplasms; Positron-Emission Tomography; Quantum Theory; Spectrometry, Fluorescence; Spectrophotometry, Infrared; Tomography, Emission-Computed, Single-Photon; Ultrasonography, Doppler

PubMed: 16614313
DOI: 10.1161/01.RES.0000216870.73358.d9

Review

Authors: Shaiju S Nazeer, Hari Sreedhar, Vishal K Varma...

Infrared spectroscopic tissue imaging is a potentially powerful adjunct tool to current histopathology techniques. By coupling the biochemical signature obtained through infrared spectroscopy to the spatial information offered by microscopy, this technique can selectively analyze the chemical composition of different features of unlabeled, unstained tissue sections. In the past, the tissue features that have received the most interest were parenchymal and epithelial cells, chiefly due to their involvement in dysplasia and progression to carcinoma; however, the field has recently turned its focus toward stroma and areas of fibrotic change. These components of tissue present an untapped source of biochemical information that can shed light on many diverse disease processes, and potentially hold useful predictive markers for these same pathologies. Here we review the recent applications of infrared spectroscopic imaging to stromal and fibrotic regions of diseased tissue, and explore the potential of this technique to advance current capabilities for tissue analysis.

Topics: Animals; Fibrosis; Humans; Molecular Imaging; Spectrophotometry, Infrared

PubMed: 28888785
DOI: 10.1016/j.biocel.2017.09.003

Review

Authors: Boone M Prentice, Richard M Caprioli, Vincent Vuiblet...

In this review, we will highlight technologies that enable scientists to study the molecular characteristics of tissues and/or cells without the need for antibodies or other labeling techniques. Specifically, we will focus on matrix-assisted laser desorption/ionization imaging mass spectrometry, infrared spectroscopy, and Raman spectroscopy.

Topics: Humans; Kidney; Kidney Diseases; Molecular Imaging; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Spectrophotometry, Infrared; Spectrum Analysis, Raman; Vibration

PubMed: 28750926
DOI: 10.1016/j.kint.2017.03.052

Authors: Adrian Cernescu, Michał Szuwarzyński, Urszula Kwolek...

Mid-infrared absorption spectroscopy has been used extensively to study the molecular properties of cell membranes and model systems. Most of these studies have been carried out on macroscopic samples or on samples a few micrometers in size, due to constraints on sensitivity and spatial resolution with conventional instruments that rely on far-field optics. Properties of membranes on the scale of nanometers, such as in-plane heterogeneity, have to date eluded investigation by this technique. In the present work, we demonstrate the capability to study single bilayers of phospholipids with near-field mid-infrared spectroscopy and imaging and achieve a spatial resolution of at least 40 nm, corresponding to a sample size of the order of a thousand molecules. The quality of the data and the observed spectral features are consistent with those reported from measurements of macroscopic samples and allow detailed analysis of molecular properties, including orientation and ordering of phospholipids. The work opens the way to the nanoscale characterization of the biological membranes for which phospholipid bilayers serve as a model.

Topics: Limit of Detection; Lipid Bilayers; Microscopy, Atomic Force; Phospholipids; Spectrophotometry, Infrared; Spectroscopy, Fourier Transform Infrared

PubMed: 30074379
DOI: 10.1021/acs.analchem.8b00485

Review

Authors: Makoto Uyama

Hair is important to our appearance as well as to protect our heads. Human hair mainly consists of proteins (80-85%), melanin pigments (0-5%), water (10-13%), and lipids (1-6%). The physicochemical properties of hair have been studied for over 100 years. However, they are not yet thoroughly understood. In this review, recent progress and the latest findings are summarized from the following three perspectives: structural characteristics, delivery and distribution of active ingredients, and hair as a template. The structural characteristics of hair have been mainly investigated by microscopic and/or spectroscopic techniques such as atomic force microscopy integrated with infrared spectroscopy (AFM-IR) and rheological measurements. The distribution of active ingredients has been generally evaluated through techniques such as nanoscale secondary ion mass spectrometry (NanoSIMS). And finally, attempts to explore the potential of hair to be used as a substrate for flexible device fabrication will be introduced.

Topics: Hair; Humans; Microscopy, Atomic Force; Melanins; Chemical Phenomena; Spectrometry, Mass, Secondary Ion; Rheology; Spectrophotometry, Infrared; Lipids; Water; Proteins

PubMed: 38825536
DOI: 10.5650/jos.ess23203

Review

Authors: Kevin V Hackshaw, Joseph S Miller, Didem P Aykas...

Vibrational spectroscopy (mid-infrared (IR) and Raman) and its fingerprinting capabilities offer rapid, high-throughput, and non-destructive analysis of a wide range of sample types producing a characteristic chemical "fingerprint" with a unique signature profile. Nuclear magnetic resonance (NMR) spectroscopy and an array of mass spectrometry (MS) techniques provide selectivity and specificity for screening metabolites, but demand costly instrumentation, complex sample pretreatment, are labor-intensive, require well-trained technicians to operate the instrumentation, and are less amenable for implementation in clinics. The potential for vibration spectroscopy techniques to be brought to the bedside gives hope for huge cost savings and potential revolutionary advances in diagnostics in the clinic. We discuss the utilization of current vibrational spectroscopy methodologies on biologic samples as an avenue towards rapid cost saving diagnostics.

Topics: Magnetic Resonance Spectroscopy; Metabolome; Metabolomics; Spectrophotometry, Infrared; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Vibration

PubMed: 33076318
DOI: 10.3390/molecules25204725

Authors: Matthias J A Vink, Fred A M G van Geenen, Giel Berden...

Agrochemicals frequently undergo various chemical and metabolic transformation reactions in the environment that often result in a wide range of derivates that must be comprehensively characterized to understand their toxicity profiles and their persistence and outcome in the environment. In the development phase, this typically involves a major effort in qualitatively identifying the correct chemical isomer(s) of these derivatives from the many isomers that could potentially be formed. Liquid chromatography-mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy are often used in attempts to characterize such environment transformation products. However, challenges in confidently correlating chemical structures to detected compounds in mass spectrometry data and sensitivity/selectivity limitations of NMR frequently lead to bottlenecks in identification. In this study, we use an alternative approach, infrared ion spectroscopy, to demonstrate the identification of hydroxylated derivatives of two plant protection compounds (azoxystrobin and benzovindiflupyr) contained at low levels in tomato and spinach matrices. Infrared ion spectroscopy is an orthogonal tandem mass spectrometry technique that combines the sensitivity and selectivity of mass spectrometry with structural information obtained by infrared spectroscopy. Furthermore, IR spectra can be computationally predicted for candidate molecular structures, enabling the tentative identification of agrochemical derivatives and other unknowns in the environment without using physical reference standards.

Topics: Agrochemicals; Chromatography, Liquid; Tandem Mass Spectrometry; Spectrophotometry, Infrared; Magnetic Resonance Spectroscopy

PubMed: 36214158
DOI: 10.1021/acs.est.2c03210

Authors: Verónica Fernández-González, Jose Manuel Andrade, Borja Ferreiro...

The EU goal to reduce marine plastic litter by ca. 30% by 2020 stressed the need to deploy analytical methods to ascertain the polymeric nature of a residue. Furthermore, as plastics age under natural conditions and usual databases do not include their weathered spectra, (micro)plastics in environmental samples may be unidentified. In this paper, polyamide (nylon) microplastics weathering was monitored because of its ubiquity in household commodities, clothes, fishery items and industry, whose residues end up frequently in the environment. Infrared spectra (ATR and microreflectance) and Scanning Electron Microscopy (SEM) images were collected periodically while exposing nylon to controlled weathering. It was seen that ATR was more sensitive than microreflectance to monitor the structural evolution of polyamide and that the spectra and the surface of weathered microplastics showed remarkable differences with the pristine material, which stresses the need for considering its evolution when identifying microplastics in environmental studies. The evolution of six band ratios related to the chemical evolution of this polymer are presented. SEM images revealed the formation of secondary microplastics at the most advanced weathering stages of polyamide.

Topics: Environmental Monitoring; Microplastics; Nylons; Plastics; Spectrophotometry, Infrared; Water Pollutants, Chemical

PubMed: 34280799
DOI: 10.1016/j.saa.2021.120162

Review

Authors: Robby Fritzsch, Samantha Hume, Lucy Minnes...

Ultrafast two-dimensional infrared (2D-IR) spectroscopy has provided valuable insights into biomolecular structure and dynamics, but recent progress in laser technology and data analysis methods have demonstrated the potential for high throughput 2D-IR measurements and analytical applications. Using 2D-IR as an analytical tool requires a different approach to data collection and analysis compared to pure research applications however and, in this review, we highlight progress towards usage of 2D-IR spectroscopy in areas relevant to biomedical, pharmaceutical and analytical molecular science. We summarise the technical and methodological advances made to date and discuss the challenges that still face 2D-IR spectroscopy as it attempts to transition from the state-of-the-art laser laboratory to the standard suite of analytical tools.

Topics: Animals; Equipment Design; Humans; Models, Molecular; Protein Conformation; Proteins; Spectrophotometry, Infrared

PubMed: 32051976
DOI: 10.1039/c9an02035g

Authors: André Guendel, Alexander Hilo, Hardy Rolletschek...

Fingerprint analysis is a common technique in forensic and criminal investigations. Similar techniques exist in the field of infrared spectroscopy to identify biomolecules according to their characteristic spectral fingerprint features. These unique markers are located in a wavenumber range from 1800 to 600 cm in the mid infrared region. Here, a novel bioanalytical concept of correlating these spectral features with corresponding mass spectrometry datasets to unravel metabolic clusters within complex plant tissues was applied. As proof of concept, vascular bundles of oilseed rape () were investigated, one of the most important and widely cultivated temperate zone oilseed crops. The link between mass spectrometry data and spectral data identified features that co-aligned within both datasets. Regions of origin were then detected by searching for these features in hyperspectral images of plant tissues. This approach, based on co-alignment and co-localization, finally enabled the detection of eight distinct metabolic clusters, reflecting functional and structural arrangements within the vascular bundle. The proposed analytical concept may assist future synergistic research approaches and may lead to biotechnological innovations with regard to crop yield and sustainability.

Topics: Brassica napus; Mass Spectrometry; Plant Vascular Bundle; Spectrophotometry, Infrared; Metabolomics

PubMed: 34827716
DOI: 10.3390/biom11111717