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Online Identification of Flavones from Flos Chrysanthemi by LC–MS-IT-TOFThe use of medicinal herbs as alternative treatment methods continues to grow. With this escalating use has come an increasing interest in determining the chemical compositions of these herbs in order to obtain a better understanding of their makeup and effects. In this study, Flos Chrysanthemi, a commonly used traditional Chinese medicine that has been cultivated for centuries, was analyzed to identify the main flavone compositions in one original breed of Flos Chrysanthemi (Hangbaiju) in China.
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Meeting the Surge in Demand for Seafood Screening on the Gulf CoastThe authors look at the use of QuEChERS in the ongoing testing program in the gulf.
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Advances in TOF-MS-Based Screening for Food Safety Residue Analysis with a Positive ApproachMass spectrometry plays an increasingly significant role in the analysis of residues and contaminants in food. Here we will illustrate how the combination of ultrahigh-pressure liquid chromatography (UHPLC) and high-resolution time-of-flight-mass spectrometry (TOF-MS) is used to generate a screen of veterinary drug residues in products of animal origin. The use of UHPLC–TOF-MS and dedicated, workflow directed software allows rapid screening for large numbers of residues and automated quantification of positive samples. In addition, we illustrate how the data generated using MSE acquisition mode enable critical structural information to be collected, which offers additional selectivity and confirmatory data for compound identification and facilitates elucidation of the structure of newly discovered compounds.
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Using LC–oa-TOF MSE with a Multivariate Statistical Sample Statistical Sample Profiling Strategy to Distinguish Chinese Red Ginseng from Korean Red GinsengBoth Chinese ginseng and Korean ginseng are similar plant species and undergo similar handling procedures when harvested and processed for sale. Despite their similarities, Korean ginseng commands a higher price than Chinese ginseng on the open market and is believed to produce different clinical effects than Chinese ginseng. Chinese researchers are now employing new techniques on the two varieties of ginseng to understand their chemical differences. HPLC/UV-based strategies for distinguishing the two types of ginseng have proven to be mostly ineffective due to lack of resolution. Using UltraPerformance liquid chromatography/orthogonal acceleration (oa)–TOF mass spectrometry and exact mass measurement, the authors developed a high-resolution method using multivariate statistical analysis for separating and identifying differences between Chinese ginseng and Korean ginseng at the molecular level.
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Ultratrace Aluminum Analysis of Nutritional Intravenous Solution Components in 1-Propanol Using GFAAS (PDF)This article describes how ultratrace aluminum analysis of two nutritional intravenous solution components with limited water solubility can be performed by graphite furnace atomic absorption spectroscopy (GFAAS) with dissolution in 1-propanol.
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Why and How to Avoid Ionic Contamination in Water Used for LC–MS AnalysesIonic contaminants in the water used in UHPLC analyses with MS detection method lead to adduct formation and reduced analytical signals because of ion suppression. In MS, the preferred ion type is the protonated molecular ion, especially in peptide analysis, since the partially mobile proton charge enables more meaningful fragmentation analysis, as compared to a sodiated peptide ion.
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Spectroscopic Monitoring of the Enrichment of Chlorin e6 in Tumors of the SkinFor the optimization of photodynamic therapy the spectroscopic detection of photosensitizer molecules, which are selectively enriched in tumour cells, can be useful.
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Using LC–oa-TOF MSE with a Multivariate Statistical Sample Statistical Sample Profiling Strategy to Distinguish Chinese Red Ginseng from Korean Red GinsengBoth Chinese ginseng and Korean ginseng are similar plant species and undergo similar handling procedures when harvested and processed for sale. Despite their similarities, Korean ginseng commands a higher price than Chinese ginseng on the open market and is believed to produce different clinical effects than Chinese ginseng. Chinese researchers are now employing new techniques on the two varieties of ginseng to understand their chemical differences. HPLC/UV-based strategies for distinguishing the two types of ginseng have proven to be mostly ineffective due to lack of resolution. Using UltraPerformance liquid chromatography/orthogonal acceleration (oa)–TOF mass spectrometry and exact mass measurement, the authors developed a high-resolution method using multivariate statistical analysis for separating and identifying differences between Chinese ginseng and Korean ginseng at the molecular level.
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Raman Spectroscopy of DocumentsDocuments have been investigated to determine the feasibility of utilizing Raman and SERS Raman spectroscopy for the identification and characterization of inks on paper. Fluorescence reduction methods have been employed to facilitate the analysis by reducing the nascent fluorescence from paper and ink. Furthermore, ink crossings were investigated to demonstrate that ink applied after creation of a document could be differentiated from the originally applied ink.
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Meeting the Surge in Demand for Seafood Screening on the Gulf CoastThe authors look at the use of QuEChERS in the ongoing testing program in the gulf.
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The Applicability of Field-Portable GC–MS for the Rapid Sampling and Measurement of High-Boiling-Point Semivolatile Organic Compounds in Environmental SamplesIn this study we report on the use of a field-portable GC-MS with rapid sampling techniques such as solid-phase micro extraction, purge-and-trap, thermal desorption, and heated headspace to provide a fast response for in-field-SVOCs analyses for a wide variety of environmental-type samples including potable waters, tea, plants and road gravel. We will show that this field-portable approach can provide the required sensitivity, selectivity for the effective analysis of SVOCs with very high boiling points such as polycyclic aromatic hydrocarbon (PAHs), pesticides, phenolic compounds and phthalate esters in a number of different field-based samples, in less than 10 minutes.
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The Exception to the Conference Industry's RuleFor anyone who makes his or her living in the field of analytical chemistry, and more specifically, in the fields of chromatography or spectroscopy, the debate concerning the state of the conference industry is well known to say the least.
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Mars Express Finds Evidence of Liquid Water on MarsSince the discovery of gullies on Mars in 2000, NASA has endeavored to re-image areas known to have them. Now for the first time, using before and after images taken of the same region on Mars, a dune gully flow is shown to have happened very recently.
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Single Multipoint Calibration Curve for Discovery BioanalysisA single calibration curve run with staggered calibrants bracketing the unknowns is compared to running complete duplicate calibration curves, one at the beginning and one at the end of unknown sample analysis in an effort to accelerate discovery bioanalysis.
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High-Throughput Trace Analysis Using SERS-Coated Microtiter Plates with a Raman Plate ReaderSurface-enhanced Raman spectroscopy (SERS) has been studied extensively over the last few decades with many advances in preparation of SERS substrates and coatings. While the bulk of the research in SERS substrate preparation has been devoted to pushing detection limits to higher sensitivity for measurement of single samples, the application of SERS to high-throughput analysis has been largely ignored. In this article, we present the use of commercially available SERS-coated microtiter plates in a dedicated Raman microtiter plate reader, enabling high-throughput trace analysis measurements. This article also describes the SERS substrate, the high-throughput plate reader, and preliminary results from samples representing trace analysis of explosives, nerve agents, pharmaceuticals, and biological compounds.
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ADME/Pharmacokinetic Studies from Serum and Plasma: Improvements in Sample Preparation and LC–MS Analysis of Therapeutic OligonucleotidesThe authors discuss improvements in sample preparation for ADME/pharmacokinetic studies of therapeutic oligonucleotides.
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Phosphorylation Site Localization Using Probability-Based ScoringThe development of a phosphorylation probability scoring tool in an automated data search engine resolves ambiguity in site localization when compared to manual methods.
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Using LC–oa-TOF MSE with a Multivariate Statistical Sample Statistical Sample Profiling Strategy to Distinguish Chinese Red Ginseng from Korean Red GinsengBoth Chinese ginseng and Korean ginseng are similar plant species and undergo similar handling procedures when harvested and processed for sale. Despite their similarities, Korean ginseng commands a higher price than Chinese ginseng on the open market and is believed to produce different clinical effects than Chinese ginseng. Chinese researchers are now employing new techniques on the two varieties of ginseng to understand their chemical differences. HPLC/UV-based strategies for distinguishing the two types of ginseng have proven to be mostly ineffective due to lack of resolution. Using UltraPerformance liquid chromatography/orthogonal acceleration (oa)–TOF mass spectrometry and exact mass measurement, the authors developed a high-resolution method using multivariate statistical analysis for separating and identifying differences between Chinese ginseng and Korean ginseng at the molecular level.
Latest:
Using LC–oa-TOF MSE with a Multivariate Statistical Sample Statistical Sample Profiling Strategy to Distinguish Chinese Red Ginseng from Korean Red GinsengBoth Chinese ginseng and Korean ginseng are similar plant species and undergo similar handling procedures when harvested and processed for sale. Despite their similarities, Korean ginseng commands a higher price than Chinese ginseng on the open market and is believed to produce different clinical effects than Chinese ginseng. Chinese researchers are now employing new techniques on the two varieties of ginseng to understand their chemical differences. HPLC/UV-based strategies for distinguishing the two types of ginseng have proven to be mostly ineffective due to lack of resolution. Using UltraPerformance liquid chromatography/orthogonal acceleration (oa)–TOF mass spectrometry and exact mass measurement, the authors developed a high-resolution method using multivariate statistical analysis for separating and identifying differences between Chinese ginseng and Korean ginseng at the molecular level.
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Quantitative Proteomic Workflow for Discovery of Early Rejection Kidney Transplant Peptide Biomarkers and Subsequent Development of SRM Assays in UrineThe authors discuss a noninvasive method for determining early indications of the rejection of a kidney transplant.
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FT-IR Microscopic Analysis of Polymer Laminate Samples Including Transmission and ATR SpectroscopyPolymer laminates typically make complex samples for infrared analysis, comprising multiple layers with defined thicknesses, in some cases less than 10 µm. When measuring extremely narrow laminate layers, the use of attenuated total reflectance (ATR) may provide improved spectra of the laminate cross-section, because ATR microscope objectives offer a greater spatial resolution than transmission due to additional magnification. This paper details the preparation of polymer laminate sample cross-sections and the collection of transmission and ATR spectra of various layers. Further analysis of the laminate spectra will also be explored utilizing a multivariate curve resolution (MCR) algorithm. An example laminate sample is examined utilizing all the tools available on a standard FT-IR microscope.
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Quantitative Proteomic Workflow for Discovery of Early Rejection Kidney Transplant Peptide Biomarkers and Subsequent Development of SRM Assays in UrineThe authors discuss a noninvasive method for determining early indications of the rejection of a kidney transplant.
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Determining Trace Elements in Edible Oils Using Inductively Coupled Plasma–Optical Emission SpectrometryThis paper describes the analysis of edible oils radial view ICP-OES. Information is provided regarding the most suitable wavelengths, background correction, and integration times. Results of a detection limit study are presented. The accuracy of the analytical method is validated using soybean, olive, and corn oil matrices.
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Analysis of Solar Silicon Using High-Throughput SpectroscopyInfrared spectroscopy is a powerful analysis technique used in the semiconductor industry to ensure the quality of silicon and silicon wafers. The authors discuss the use of an inexpensive, lab-based system to measure carbon and oxygen concentrations in silicon to the level of precision required by the solar silicon industry.
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Phase-, Time-, and Space-Resolved Step-Scan FT-IR Spectroscopy: Principles and Applications to Dynamic and Heterogenous Systems (PDF)This article reviews the principles and major applications of step-scan Fourier transformyy}infrared spectroscopy, an important means for solving challenging problems in many areas of science and technology.
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Spectroscopic Monitoring of the Enrichment of Chlorin e6 in Tumors of the SkinFor the optimization of photodynamic therapy the spectroscopic detection of photosensitizer molecules, which are selectively enriched in tumour cells, can be useful.
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Tech Note: High-Resolution Ultrasonic Spectroscopy for Analysis of Chemical Reactions in Real Time (PDF)This article discusses direct real-time monitoring of chemical reactions, an important tool in industrial processes in industries such as chemical, biotechnology, food, and pharmaceutical.
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SERS Comes of Age for Molecular DetectionSince it was first described in 1974, surface-enhanced Raman spectrometry (SERS) has been thought to offer significant potential for a range of different applications. The theoretical sensitivity and specificity envisaged for this powerful technique has engaged scientists for many years, but practical challenges have hindered its routine adoption. Now, a new approach combines a robust and reliable substrate with expertise in surface chemistry and molecular biology on a platform that can be adapted for a wide variety of Raman instrumentation and customized routine applications.
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Efficient Mitigation of Fluorescence in Raman Spectroscopy Using SSE™Handheld Raman spectrometers are now designed and built for practical everyday use in a vast array of applications. The new BRAVO by Bruker takes handheld Raman Spectroscopy to a new level, overcoming the limitations of previously available systems such as limited wavelength accuracy, non-safe laser usage and fluorescence interference. Now with BRAVO wavelength accuracy is significantly better than competitive devices resulting in the highest data consistency and the BRAVO incorporates new technology called Sequentially Shifted Excitation (SSE™) to mitigate fluorescence.
