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..
Mass spectrometry has become a fundamental tool for compound identification or confirmation by virtue of its ability to obtain elemental composition determination (formula identification) by accurate mass measurements. The speed, sensitivity, and ease of interfacing the technique with gas chromatography and liquid chromatography make it the technique of choice for many applications. However, accurate mass measurements must be made with care, and sometimes they can require careful calibration procedures and validation methods. In addition to accurate mass measurements, the isotope abundance distribution also provides information unique to a given chemical formula. However, the mass spectral accuracy required for accurate isotope modeling has not been easy to obtain previously. More recent approaches (1–3) that calibrate the spectral line-shape show promise in obtaining the necessary level of spectral accuracy but still require careful calibration methods with the use of known standards. This article..
The authors review the operating principles of a silicon Raman laser and show that by introducing a longitudinal variation of the waveguide width in the cavity, the lasing efficiency can be increased significantly.
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.
Combining the three techniques of LC, MS, and NMR into one integrated system provides optimal use of NMR intrument time by using information-rich MS data to automatically guide the NMR operation. Here, the authors explore just this type of system.
September 2006. The authors rapidly acquire complete vibrational spectra in the fingerprint region using a single femtosecond laser for broadband coherent anti-Stokes Raman scattering (CARS) microscopy to image spatially variant compositions of condensed-phase samples.
EP-IR Spectrometry -- a cost-effective, rugged and compact high scanning speed full-spectrum technology -- provides a means to simultaneously measure spectrally overlapping compounds without false positive response, considerably exceeding TUEV and MCERTS analytical requirements for cross sensitivity.
Recent evidence that the phthalate plasticizers may cause health problems, particularly in children, has resulted in many countries prohibiting the use of phthalates in toys and clothing. The United States Child Safety Law actually prohibits the presence of several phthalate compounds at levels exceeding 0.1 wt % even though the commercial levels are often greater than 10%. While ATR spectroscopy works well for identifying phthalates at commercial levels, a more sensitive technique is required to detect trace levels.
Plutonium is distributed globally in the Earth's surface environment as a result of atmospheric weapons tests, nuclear accidents, and nuclear fuel reprocessing. Mass spectrometry (MS), in particular, sector field ICP-MS, now is used widely to determine Pu activities and isotope ratios; 240Pu/239 is very useful in determining Pu origin. Determination of Pu by ICP-MS involves dissolution, column separation, and the MS determination; detection limits are 0.1–10 fg for each isotope. Applications of the determination of sector field ICP-MS to studies of environmental Pu include discerning sources of contamination near the Chernobyl reactor, and chronology of recent aquatic sediments.
Off-line 2-D LC–MS-MS represents a powerful alternative to on-line methodologies for protein identification from complex proteomes, improving the chromatographic resolution of digest peptide mixtures, even for low-abundance proteins. Here, the authors provide a detailed comparison of the two techniques.