This study aimed to establish a fast, accurate method for quality evaluation of herbal medicine using NIR and chemometrics with ultraviolet-visible spectrophotometry (UV-vis) as a standard method to determine the total flavonoids content.
Researchers at Heriot-Watt University deploy the Chromacity OPO for active long-range FTIR spectroscopy to acquire high-resolution gas absorption spectra over 200 m.
Metallomics seeks to understand the metallobiochemistry of cells and organisms in health and disease. This article explains the principle of laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) for imaging applications and highlights its potential to provide additional insights in bioanalysis and metallomics.
In this paper, a one-time digestion method for the determination of arsenic (As), antimony (Sb), selenium (Se), and mercury (Hg) in geological samples was established.
In this short overview, we consider cases for diffuse reflection spectroscopy and introduce the Kubelka-Munk diffuse reflectance formula. We conclude by comparing diffuse transmittance, diffuse reflectance, logarithmic transforms of both, and the Kubelka-Munk transform for mid-infrared spectroscopy of the same sample.
A multiscale convolutional neural network (MsCNN) was used to screen Raman spectra of the hepatitis B serum, achieving higher classification accuracy compared to traditional machine learning methods.
This approach provides traceable and reliable quantitative elemental analysis of airborne particles for on-site environmental measurement with portable instrumentation.
In this article, the basic principles, advantages, and limitations of different optical techniques for obtaining seed vigor estimates are introduced and reviewed, and the key technology of non-destructive optical detection of single seeds will be discussed.
We tackle one of the most common questions to arise when picking a Raman spectroscopy laser, “Should I choose a single, or multi-spatial mode laser for my application?”
Long chain fatty acids (LCFAs) function as a source of metabolic energy, substrates for membrane biogenesis, and storage of metabolic energy. Oxylipins, oxygenated derivatives of LCFAs, regulate the activity of many cellular processes. Existing methods for the analysis of LCFAs and oxylipins have limited compound coverage and sensitivity that, therefore, prevent their application in biological studies. In this work, we developed a high-throughput LC–MS method for analysis of 51 LCFAs and oxylipins. LCFAs and oxylipins were first extracted from biological samples via solid-phase extraction. The extracted molecules were analyzed by targeted comparative metabolomics. Saturated and monounsaturated LCFAs were analyzed in single ion reaction mode, while polyunsaturated LCFAs and oxylipins were analyzed in multiple reaction monitoring mode. Using this method, we successfully quantified 31 LCFAs and oxylipins from mouse livers.
UV-Vis-NIR can be used to understand how ancient buildings were constructed. Here, a UV-Vis-NIR and EDXRF spectrophotometer were used to analyze glazed tiles that comprised a historical site built in Ancient China.
Perovskites are known to be useful for fabrication of solar cells, and their crystalline structure plays an important role in their electronic properties. Here, we show how Raman analysis is able to confirm the presence of the required crystalline phase for solar cell production.
Spectral reflectance is a non-destructive method that is applicable to remote sensing and may be used to measure the chlorophyll content in a crop, which indicates the photosynthetic capacity, growth cycles, and degrees of stress (such as disease, insect infestation, and heavy metal stress) on plant ecosystems. This vis-NIR spectral reflectance method measures leaf chlorophyll using a wavelet analysis algorithm approach.
The implementation of 120 open-path spectroscopy analyzers at oil refineries has taught us lessons about compound identification, target species detectability, interferences, and data management, which can help spectroscopists generate more accurate data when monitoring air quality.
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.
Nitrite poses health risks. This study evaluates the results of using tannic acid- protected fluorescence copper nanoclusters (TA-CuNCs) to detect nitrite in food.
Plasma spray–deposited metal films are used in many industrial applications. This study shows how high resolution terahertz time-domain spectroscopy (THz-TDS) can be used to analyze and characterize such films.
The United States Pharmacopeia–National Formulary (USP–NF) has contributed to ensuring the quality of dietary supplements, foods, and medicines for more than 200 years. This overview explains the use of vibrational spectroscopy techniques in meeting USP–NF requirements and how the information is organized.
Analysis of the compositional variation in living cells is essential for understanding biological processes. Single-cell elemental analysis by triple-quadrupole ICP-MS is emerging as a selective, highly sensitive, and potentially high-throughput technique for the study of constitutive elements, and uptake of metallodrugs (or metal-containing nanomaterials) in single cells.
This study uses hyperspectral imaging (HSI) technology, in synergy with machine learning and deep learning algorithms, to innovate a non-destructive method for the assessment of chicken freshness.
The determination of metals in hygienic face masks is important for global heath at this time. Following the guidelines of ISO 18562-4, an ICP-OES method is described including sample preparation, analysis, and validation of the methodology.
Size-exclusion chromatography (SEC), with the use of ammonium acetate buffer, can be coupled on-line to electrospray ionization MS for the characterization of size variants of therapeutic monoclonal antibodies (mAbs). A quadrupole time-of-flight (QTOF) MS system was employed, and the MS method was optimized to achieve favorable sensitivity for high-mass detection, while maintaining the structural integrity of the aggregates (or high molecular weight species) and fragments (or low molecular weight species).
We examine the feasibility of FT-NIR for the detection of early fungal infections in citrus.
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.
This new terahertz method provides a theoretical reference for studying the relationship between biomolecules and water.
To study the effect of various extractants on the structure of peat humic acid, peat humic acid was extracted using NH3·H2O, Na2CO3, NaHCO3, and Na2SO3 via alkali-extraction and acid-precipitation methods.
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).
A simple colorimetric and fluorescent dual-channel chemosensor was designed and synthesized to identify Hg2+ in an aqueous solution with demonstrated high selectivity and sensitivity.
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.
This study examines the fluorescence enhancement effects of forsythoside E, one of metabolites of Forsythia suspensa, on human serum albumin (HSA) and bovine serum albumin (BSA) under simulated physiological conditions.