The SCGD ambient-atmosphere microplasma has emerged as an alternate excitation source for atomic emission spectroscopy that is able to perform admirably compared to established, conventional approaches—with lower cost.
In recent years, advances in X-ray optics and detectors have enabled the commercialization of laboratory μXRF spectrometers with spot sizes of ~3 to 30 μm that are suitable for routine imaging of element localization, which was previously only available with scanning electron microscopy (SEM-EDS). This new technique opens a variety of new μXRF applications in the food and agricultural sciences, which have the potential to provide researchers with valuable data that can enhance food safety, improve product consistency, and refine our understanding of the mechanisms of elemental uptake and homeostasis in agricultural crops. This month’s column takes a more detailed look at some of those application areas.
Per- and poly-fluoroalkyl substances (PFAS) are a family of potentially thousands of synthetic compounds that have long been used in the manufacture of a variety of common products with stain-repellent and nonstick properties. Their signature strong fluorine and carbon bonds make them difficult to break down and, as a result, they are among the most persistent of today’s environmental pollutants. Alarmingly, PFAS can be found in drinking water and have been shown to accumulate in the body with the potential to cause multiple health problems, such as hormone disruption and cancer. Advances in mass spectrometry have facilitated the detection of known PFAS contaminants as well as the identification of poorly studied and novel compounds in watersheds. This article explores the detection of known and novel PFAS contaminants in aqueous film-forming foams and raw drinking water sources in North Carolina, using new advances in mass spectrometry and data acquisition to improve identification and quantitation.
This month’s column evaluates the capability of inductively coupled plasma–mass spectrometry (ICP-MS) to reduce the impact of doubly charged rare-earth element (REE) interferences on the quantitation of the metalloids, arsenic (As), and selenium (Se) in water and biological matrices.
Here we conduct an evaluation of significant operational parameters of IR microscopy for accurately determining the size of microplastics, with the overarching goal of outlining performance parameters that will help in the standardization of microplastics analysis.
A novel approach to NIR spectral sensing, using a miniaturized fully-integrated multipixel array of resonant-cavity-enhanced InGaAs photodetectors, enables sensors with a millimeter-scale footprint and wafer-scale fabrication. This multipixel sensor does not measure the full spectrum, but rather a limited number of spectral regions with limited resolution (50–100 nm).
The relationship between the complexation amount of thorium (Th) and Suwannee River fulvic acid (SRFA) and the changes in Th concentration and pH were studied using differential spectroscopy and 3D excitation-emission matrix fluorescence spectroscopy (3D EEM).
This research investigates the application of laser-induced breakdown spectroscopy (LIBS) and machine learning (ML) for detecting elemental composition of food, using rice as an example.
A review of exponential signal models with machine learning in nuclear magnetic resonance (NMR) spectroscopy is discussed here.
Determining the printing sequences of crossed writings and seal stamps is often difficult because the most common methods used are expensive, time-consuming, and cumbersome. A new method using Raman spectral area scanning offers a better alternative while conducting pigment analysis and determining intersection sequences of writings and seal stamps. We explain why.
A more successful blueprint for analyzing Raman spectral data is outlined by following the 11 important steps, which are outlined here.
Spectroscopic ellipsometry, correlated with UV-vis-NIR spectroscopy, is used to determine the optical constants of thin films, such as in GexSb40-xSe60 chalcogenide glass.
The study developed an effective mid-infrared spectroscopic identification model, combining principal component analysis (PCA) and support vector machine (SVM), to accurately determine the geographical origin of five types of millet with a recognition accuracy of up to 99.2% for the training set and 98.3% for the prediction set.
We investigate the effect of an applied electric field on the laser-induced titanium plasma for laser induced breakdown spectroscopy (LIBS) for the purpose of assessing electron density with respect to laser energy.
The significance of the smaller spectral region of the Raman spectrum, defined as the “fingerprint in the fingerprint” region, cannot be overstated when it comes to active pharmaceutical ingredient identity testing (API).
This article discusses coherent Raman imaging and how it can visualize and quantify cutaneous pharmacokinetics (PK).
Graphene exhibits special properties, such as high strength and high electrical and thermal conductivity and as such is highly desirable for key electronic components. A new Raman spectroscopy sampling technique has been applied to the characterization of batches of graphene that provides a simple, at-line method for obtaining key product data.
In the agrifood sector, soil sampling and analysis is a prerequisite for accurate fertilizer management and to monitor the accumulation of heavy metals in soils. In this study, energy dispersive X-ray fluorescence (EDXRF) was used to analyze soils with variable textures (clay and sandy) and the percent recovery of elements was compared, as a measure of accuracy.
A proposed solution is a coal species classification method that combines terahertz time-domain spectroscopy with machine learning - specifically, principal component analysis (PCA) and cluster analysis (CA). By using terahertz (THz) time-domain spectroscopy (TDS), the absorption coefficient, dielectric constant, and refractive index of each sample were obtained from lignite, bituminous coal, and anthracite samples.
The case studies presented here successfully demonstrate the use of inline Raman spectroscopic analysis to estimate solvent content during the solvent exchange and distillation operations in the synthesis of active pharmaceutical ingredients.
In this work, a stable variable selection method based on variable stability correction (VSC) and modified iterative predictor weighting-partial least squares (mIPW-PLS) is proposed for the quantitative analysis of steel samples by laser-induced breakdown spectroscopy (LIBS).
This study uses Fourier transform infrared (FT-IR) spectroscopy to analyze how the globular protein ovalbumin's secondary structures transition under varying pH conditions in the presence of the cosolvent xylitol, highlighting the role of noncovalent interactions in these conformational changes.
Here, we compare XRD and FT-IR for analysis of suspect counterfeit pharmaceuticals to determine how the techniques can be used in a complementary fashion.
Using confocal Raman imaging and other advanced measurement techniques, we study the localized strain characteristics of tungsten diselenide (WSe2), an important nanomaterial used for optoelectronic device applications.
Webinar Date/Time: Wed, Nov 20, 2024 2:00 PM EST
This new terahertz method provides a theoretical reference for studying the relationship between biomolecules and water.
In this study, in situ Raman spectroscopy was used to detect the formation, growth, and evolution of corrosion inside a salt fog chamber. These results pave the way for monitoring the real-time observation of corrosion on metal surfaces.
In recent years, advances in X-ray optics and detectors have enabled the commercialization of laboratory μXRF spectrometers with spot sizes of ~3 to 30 μm that are suitable for routine imaging of element localization, which was previously only available with scanning electron microscopy (SEM-EDS). This new technique opens a variety of new μXRF applications in the food and agricultural sciences, which have the potential to provide researchers with valuable data that can enhance food safety, improve product consistency, and refine our understanding of the mechanisms of elemental uptake and homeostasis in agricultural crops. This month’s column takes a more detailed look at some of those application areas.