Metabolomics is a developing analytical approach that is growing rapidly in importance as a tool to improve diagnosis and treatment of disease, as well as to speed up the drug development process. Unlike genomics or proteomics, which only reveal part of what might be happening in a cell, metabolomic profiling can give an instantaneous snapshot of the entire physiology of that cell. This article describes the challenges associated with metabolomics research and new tools developed to overcome them.
The authors discuss progress in near-field IR microspectroscopy using a photothermal probe and show how it can be applied to the spectroscopic characterization of real-world samples.
The study of the interaction mechanism of nucleic acids-CTMAB with AG showed that the enhanced RLS comes from the aggregation of AG on nucleic acids through the bridged and synergistic effect of CTMAB.
Root diseases caused by soilborne plant pathogens are responsible for billions of dollars of losses annually in food, fiber, ornamental, and biofuel crops. The use of pesticides often is not an option to control plant diseases because of economic factors or potential adverse effects on the environment or human health. For this reason, many Americans are now buying pesticide-free organic foods. Organic agriculture has few options for controlling pests and thus must make full use of natural microbial biological control agents in soils that suppress diseases.
Multiline analysis, which consists of using several lines per element to detect positive or negative bias caused by spectral interferences, is an ideal way to use all the information emitted by the plasma and collected by a charge-coupled device detector. However, method development and validation become more complex. Dedicated software has been developed to overcome it, and analysis of geological samples will illustrate their benefit in achieving high reliability of results.
Assay sensitivity is the lowest concentration at which a targeted analyte can be measured and is often limited by chemical background or co-eluting interferences. FAIMS in combination with liquid chromatography (LC) and zero neutral loss tandem MS was used to remove chemical background and co-eluting interferences from the analysis of linoleic acid in cancer cell extracts. Concentration of endogenous linoleic acid was determined from back-calculation of standard calibration samples fortified with deuterium-labeled linoleic acid. No internal standard was used. LC–MS-MS analysis of the cancer cell extracts resulted in an increase in signal-to-noise ratio of 10-fold. The assay sensitivity was increased 10 times over the traditional LC–MS-MS experiment exclusively due to the new FAIMS technology.
The authors discuss the use of serial coulometric flow cells coupled online with electrospray ionization mass spectrometry in predictive assays for absorption, distribution, metabolism, excretion, toxicity (ADME/Tox), and stability implemented at early stages of drug discovery.
Signal-to-noise of a chromatographic peak from a single measurement has been used determine the performance of two different MS systems, but this parameter can no longer be universally applied and often fails to provide meaningful estimates of the instrument detection limits (IDL).
High-resolution ultrasonic spectroscopy titration analysis is a powerful new tool in research and analytical laboratory work for quantitative measurements of different processes and compounds. Here, the authors explore its potential.
State-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.
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.
The spectrometric techniques of inductively coupled plasma–optical emission spectrometry (ICP-OES) and inductively coupled plasma–mass spectrometry (ICP-MS) are compared for their applicability to regulatory water analyses, bearing in mind recent method approval changes. ICP-OES is found to be at its limit for confident detection of several elements for drinking water analysis, but is still suitable for many environmental water quality measurements. ICP-MS is the closest there is to a universally applicable technique for water analysis.
Here we describe a new compact device for electron-capture dissociation (ECD) analysis of large peptides and posttranslational modifications of proteins, which can be difficult to analyze via conventional dissociation techniques such as collision-induced dissociation (CID). The new compact device realizes ECD in a radio frequency (RF) linear ion trap equipped with a small permanent magnet, which is significantly different than the large and maintenance-intensive superconducting magnet required for conventional ECD in Fourier-transform ion cyclotron resonance mass spectrometers. In addition to its compactness and ease of operation, an additional merit of an RF linear ion trap ECD is that its reaction speed is fast, comparable to CID, enabling data acquisition on the liquid-chromatography (LC) time scale. We interfaced the linear-trap ECD device to a time-of-flight mass spectrometer to obtain ECD spectra of phosphorylated peptides injected into a liquid chromatograph, infused glycopeptides, and intact small..
State-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.
Drug discovery scientists are continually striving to improve productivity and efficiency in their workflows. From early discovery to clinical development, existing workflow bottlenecks represent an opportunity to develop solutions to speed the process and improve productivity. The key requirements for quantitative analysis are precision, accuracy, and linear dynamic range. With any quantitative instrument, the hope is that it will be applicable to a vast range of coumpounds, ruggest, and fast. New mass spectrometry (MS) technologies are being developed that meet these criteria and permit high throughput while enabling its application to areas in which speed limitations previously curtailed its practicality. In particular, in the area of ADME profiling, new MS platforms are becoming available that increase the throughput by at least 25-fold, by combining the speed of matrix-assisted laser desorption ionization (MALDI) with the specificity of triple-quadrupole MS. This is bound to greatly accelerate the ADME..
The metabolomics workflow described here combines untargeted (discovery) quadrupole time-of-flight (Q-TOF) liquid chromatography–mass spectrometry (LC–MS), targeted (confirmation) triple-quadrupole LC–MS-MS, and sophisticated data mining as an effective means to elucidate metabolite changes.
Root diseases caused by soilborne plant pathogens are responsible for billions of dollars of losses annually in food, fiber, ornamental, and biofuel crops. The use of pesticides often is not an option to control plant diseases because of economic factors or potential adverse effects on the environment or human health. For this reason, many Americans are now buying pesticide-free organic foods. Organic agriculture has few options for controlling pests and thus must make full use of natural microbial biological control agents in soils that suppress diseases.
Learn of three real-life examples of Raman microscopy in battery research, focusing on lithium batteries to better understand the process both ex- and in-situ.
Today's ion traps use advanced scanning techniques such as automatic gain control, axial modulation, and triple resonance scanning, resulting in efficient control of both ionization and optimal storage of ions in the trap during analysis. These instruments provide excellent sensitivity and quantitative data, even in "dirty" samples.
Applied Biosystems/MDS SCIEX
The need for reference materials that can be applied in the area of thin films analysis has long been realized but is still, in general, under-addressed. Alumina films of single-micrometer thickness, having either fine distributions of impurities or delta function impurity marker layers, can be prepared routinely by anodic oxidation of electropolished aluminum specimens in appropriate electrolytes. Selected films were examined by transmission electron microscopy (TEM) and analyzed by radio frequency glow discharge optical emission spectroscopy (rf-GD-OES), providing very rapid, yet high-resolution, depth-resolved analysis of these electrically insulating materials.
Although not currently used in U.S. or European aquaculture, malachite green (MG) is still an effective and inexpensive fungicide that is used in other countries, particularly in Asia. During metabolism, MG reduces to leucomalachite green (LMG) (Figure 1), which has been shown to accumulate in fatty fish tissues. Trace levels of MG and LMG residues continue to be found in fish products. In a 2005 report, MG was found in 18 out of 27 live eel or eel products imported from China to Hong Kong local market and food outlets, resulting in a government recall and destruction of all remaining products (1).
The authors discuss the ICP-MS method, its usability in environmental and geological analysis and relevant regulations, and how to address its limitations.
ICP-OES has been an important technique in the petroleum/petrochemical analysis laboratory due to its ability to determine a range of elements and concentrations in both aqueous and organic samples. This application note will demonstrate the ability of the Teledyne Leeman Labs Prodigy7 ICP-OES to determine a range of elements in petroleum samples.
The analysis of toy samples for toxic trace elements has been undertaken for many years. However, a number of recent cases of toys contaminated with heavy metals has attracted global media attention. This has resulted in an increase in the number of toy manufacturers performing their own 'in-house' testing. This 'in-house' testing is not only to ensure regulatory compliance; it is also proving significantly more cost effective than outsourcing the analysis.
This article introduces the application of high-resolution ultrasonic spectroscopy for the analysis of emulsions and suspensions.
New developments in matrix-assisted laser desorption ionization (MALDI) technology enable decoupling of the ionization source from the time-of-flight mass analyzer for operation at atmospheric pressure (AP-MALDI). This technique also can be integrated with other types of mass analyzers, such as the ion trap.
Elemental analysis in biological samples generally is achieved using flame atomic absorption spectrometry (AAS) and graphite furnace AAS (GFAAS). Flame AAS is fast, easy-to-use, and economical, but insufficiently sensitive for assays such as Se in serum and Pb/Cd in whole blood. These measurements require use of the more sensitive GFAAS. Inductively coupled plasma-mass spectrometry (ICP-MS), despite its low detection limit capabilities and wide elemental range, has had relatively little impact to date on biomedical analysis because of the popularly held conception that it is complex to use and expensive. In recent years, the instrumentation has been simplified and purchase, running, and maintenance costs have fallen. As a result, clinicians are becoming more interested in ICP-MS, although the perception that it is still much more expensive than GFAAS remains. This article provides a comparison of the costs of ICP-MS and GFAAS for biomedical sample analysis and illustrates the performance of ICP-MS for..