Raman spectroscopy is a powerful, label-free spectral imaging technique for biomedical sample measurements. The chemometric approaches described here increase the speed of data acquisition and improve the resolution of Raman images.
Food quality differences are dependent on botanical and geographical origins of primary food ingredients as well as storage and handling. Quality assessment for food materials, including cocoa and olive oil, is demonstrated by applying two-dimensional gas chromatography (GC×GC) combined with time-of-flight mass spectrometry (TOF-MS) and pattern recognition.
The results in this study indicate that NIR spectroscopy is a potentially promising approach for the rapid identification of different harvest times of Cabernet Sauvignon grapes, and the proposed technique is helpful for the prediction of ripened and over-ripened Cabernet Sauvignon grapes during the harvest time.
Extractable and leachable (E&L) testing for finished pharmaceutical products, bioprocess manufacturing systems, and medical devices is currently a subject of intense interest. The majority of the challenges encountered in analytical workflows are related to the highly complex matrices and relatively low analyte evaluation thresholds seen in E&L studies. This paper provide options for executing E&L testing to supporting regulatory submissions. There are multiple compliant routes possible, and the presented workflows and analytical solutions are only one of multiple successful approaches.
The field of analytical chemistry is well established. It’s time to develop the field of analytical biology—an emerging discipline that blends various research fields to provide a holistic view of biological phenomena.
By using green synthesized AgNPs modified by chitosan and organic acid, a simple, cost-effective, and highly selective onsite colorimetric detection method for Pd2+ and Hg2+ ions was developed.
A rapid vis-NIR spectroscopy method for determining soil particle size and quality.
Gas chromatography–mass spectrometry (GC–MS) with cold electron ionization (EI) is based on interfacing the GC and MS instruments with supersonic molecular beams (SMB) along with electron ionization of vibrationally cold sample compounds in SMB in a fly-through ion source (hence the name cold EI). GC–MS with cold EI improves all the central performance aspects of GC–MS. These aspects include enhanced molecular ions, improved sample identification, an extended range of compounds amenable for analysis, uniform response to all analytes, faster analysis, greater selectivity, and lower detection limits. In GC–MS with cold EI, the GC elution temperatures can be significantly lowered by reducing the column length and increasing the carrier gas flow rate. Furthermore, the injector temperature can be reduced using a high column flow rate, and sample degradation at the cold EI fly-through ion source is eliminated. Thus, a greater range of thermally labile and low volatility compounds can be analyzed. The extension of the range of compounds and applications amenable for analysis is the most important benefit of cold EI that bridges the gap with LC–MS. Several examples of GC–MS with cold EI applications are discussed including cannabinoids analysis, synthetic organic compounds analysis, and lipids in blood analysis for medical diagnostics.
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).
Handheld FT-Raman spectroscopy can complement GC–MS and IR in characterizing street drugs.
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.
Learn about real-time, protein analysis solutions that seamlessly couple to chromatography instruments to meet the growing demands of Industry 4.0
This study examines whether the computed spectrum can be used to accurately identify amino acids, by comparing the computer spectrum to the measured spectrum of a biological sample.
This study examines whether the computed spectrum can be used to accurately identify amino acids, by comparing the computer spectrum to the measured spectrum of a biological sample.
A new FID-FM fusion model for infrared measurements of glucose in synthetic samples is proposed, comparing prediction performance to full PLS, SMR, XGBoost, CBR, and DSFPLS modeling methods.
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.
By adding a FLIM module to the inVia Raman microscope, you can directly correlate Raman and fluorescence lifetime images with ease.
This article explains the key steps of using Raman technology to investigate carbon and carbon-based materials—such as carbon nanotubes, graphene, and carbon fibers and composites—as well as the process of analyzing the spectra.
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.
A complex fluorescence method utilizing the Sn(II)-salicylfluorescein (SAF)-cetyltrimethylammonium bromide (CTMAB) system demonstrated effective detection of Sn(II) with a linear relationship between its concentration and fluorescence intensity, along with successful application in various sample matrices with high recovery rates.
Classification and identification of different wood species are demonstrated using a portable near-infrared spectrometer, combined with four spectral pretreatment methods and three pattern recognition methods. Additional chemometric tools were used for comprehensive evaluation of classification model accuracy and complexity.
A rapid vis-NIR spectroscopy method for determining soil particle size and quality.
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.
Food contamination from mineral oil saturated hydrocarbons (MOSHs) and mineral oil aromatic hydrocarbons (MOAHs) is problematic and requires a sensitive analytical technique. These contaminants were analyzed using GC×GC with flame ionization detection (FID) and time-of-flight–MS (TOF–MS) parallel dual detection. The method provides enhanced chromatographic separation, along with the full mass spectra information, and overcomes difficult interferences, resulting in reduction of false positives over conventional GC–MS methods.
Various chemometric approaches, including four discriminant models (ELM, TLBO–ELM, KELM, and TLBO–KELM), were used to detect shrimp freshness based on near-infrared hyperspectral imaging.
A look at how the spectral properties single-phase green emission phosphor make it suitable for near-UV light-emitting diode (NUV-LED) applications.