The “selective fluorescence quenching effects” of Fe3+ ions on carbon dots are examined to gain a more comprehensive understanding of the interactions of metal ions with a variety of fluorescent materials.
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 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.
Detecting metal elements in liquid samples cannot be done efficiently by only using LIBS, but when the technique is combined with appropriate membrane materials, rapid analysis of solution samples can be realized.
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).
Webinar Date/Time: Mon, Mar 27, 2023 11:00 AM EDT
An increasing number of antibiotic residue problems in food have emerged around the world. We examine how SERS is used to identify antibiotic residues in chicken, focusing on doxycycline hydrochloride and tylosin.
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).
In this article, it is explored whether THz-TDS combined with LS-SVM can be used to effectively identify the authenticity of Panax notoginseng, a traditional Chinese medicine.
This study explores the enhanced performance of modified alternating least squares (MALS) over alternating least squares (ALS) in analyzing infrared and Raman image spectral data, highlighting the stability and computational efficiency of MALS.
The COVID-19 vaccine, and the speed at which it was developed, is the medical breakthrough of our lifetimes.
Software tools for ICP-MS and ICP-OES can help analysts to simplify method setup and reduce the potential for errors.
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.
In this study, a glycerol-fed, lab-scale E. coli bioprocess producing representative pharmaceutical compounds was monitored offline with a portable, high-sensitivity Raman spectrometer.
In this article, it is explored whether THz-TDS combined with LS-SVM can be used to effectively identify the authenticity of Panax notoginseng, a traditional Chinese medicine.
In this study, X-ray fluorescence (XRF) spectroscopy was used to analyze heavy metals in five traditional Mongolian medicines, and the results were compared to those obtained using ICP-MS.
This article discusses how FT-IR and SERS is being used to detect counterfeit pharmaceutical drugs.
As this study demonstrates, energy-dispersive X-ray fluorescence (EDXRF) and multivariate statistical analysis can be used to distinguish different classes of historical artifacts, such as ancient pottery—revealing insights about theirs origin and uses.
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.
We show how FT-IR may be used for quality control analysis of natrii sulfas, a transparent crystalline material used in natural medicine that primarily contains sodium sulfate decahydrate, crystallized from sulfate minerals.
Regulations have been imposed to set legal limits of nitrate and nitrite in water worldwide. In this study, a highly accurate and optimized ultraviolet (UV) spectroscopy method is proposed to simultaneously monitor nitrate and nitrite for rapid determination and continuous monitoring in environmental water applications.
A model has been developed to predict the “cold” or “hot” nature of Chinese medicines based on UV spectral data.
This study applied principal component regression (PCR) and partial least squares (PLS) algorithms for the spectrophotometric analysis of a drug containing antazoline hydrochloride (AN) and naphazoline hydrochloride (NP) without chemical separation. Both methods showed high accuracy and precision, with results closely matching those from a reference HPLC method, and were successfully validated for analyzing commercial pharmaceutical products.
The relationship between leaf nitrogen content (LNC) and hyperspectral remote sensing imagery (HYP) was determined to construct an estimation model of the LNC of drip-irrigated sugar beets, to enable real-time monitoring of sugar beet growth and nitrogen management in arid areas.
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.
An artificial neural network was combined with LIBS to provide a rapid and accurate coal-rock recognition method for unmanned coal mining.
A method combining inductively coupled plasma–mass spectrometry (ICP-MS) with inductively coupled plasma–optical emission spectrometry (ICP-OES) was developed for multielement determination of 50 species of major, minor, micro, and trace, rare earth, and rare elements in geological samples.
A rapid vis-NIR spectroscopy method for determining soil particle size and quality.
In this study, X-ray fluorescence (XRF) spectroscopy was used to analyze heavy metals in five traditional Mongolian medicines, and the results were compared to those obtained using ICP-MS.