Mass Spectrometry

Acid stills

Mass spectrometer

Imaging spectrograph

Realistically, 2005 was a good year for the laboratory analytical and life science instrument industry. Although growth has moderated from that experienced in the 1990s, a general rebound in worldwide industrial demand, and continued spending for life science and strong growth in Asia and North America drove instrument systems and aftermarket sales. Similar to last year, 2006 should be a year of healthy sales growth as global economic conditions support continued market expansion.

The Shamrock 163i imaging spectrograph from Andor Technology is based on a Czerny-Turner optical layout featuring a focal length of 163 mm, an entrance aperture ratio of f/3.6, and a wavelength resolution of 0.17 nm. The instrument includes interchangeable gratings and slits that allow users to select different wavelength ranges and resolutions. Andor Technology, Belfast, UK; www.andor.com

Tunable diode laser absorption spectroscopy (TDLAS) has evolved from a laboratory specialty technique to the foundation for highly sensitive and specific gas-phase sensors for the process environment. This article discusses two recently developed products, a portable trace gas monitor, and a water vapor flow sensor.

Getting light from one place to another is a key task in any spectroscopic method. Sometimes we send light through (mostly) empty space using mirrors or lenses, and sometimes we use things called fiber optics. This installment of "The Baseline" tackles fiber optics.

This year's survey of salaries and job attitudes reveals that the market seems stable, but many spectroscopists are feeling the pressure of the economy at work.

IR imaging provides a new tool for disease detection, revealing compositional and structural information in tissue previously not available with contrast staining.

Part IV of this four-part series wraps up the discussion of mass calibration, covering the "new generation" attributes that have become apparent as researchers aim to meet the calibration demands of proteomics.

The concentration dependent influence of Na+ and K+ions on mass spectra of peptides is shown with human gastrin as a model peptide. With electrospray ionization the doubly charged protonated molecule ion [M+2H]2+ is normally the preferred ionization product. However, trace amounts of alkali metal ions already form clusters (adducts) with the peptide molecule, such as [M+H+Na]2+, which become dominating at higher concentrations. With Na+/K+ concentrations below 0.1 mg/kg (ppm) only a few clusters appear, which allow the correct doubly charged molecule ion to be assigned for a subsequent MS–MS experiment. With concentrations of 10 ppm and higher the alkali clusters become the most abundant peaks in the spectrum, and the absolute sensitivity is decreased by a factor of 5–10. Experiments were performed with water and water–methanol mixtures with a known Na+/K+ +content.

Many important biological signals are triggered by the binding of a peptide hormone to its cognate receptor at the cell surface. Using stopped-flow fluorescence spectroscopy, the authors have been able to observe, in real time, ligand binding to epidermal growth factor receptors expressed at the surface of intact cells. This method allows for the measurement of kinetic association and dissociation rates with high data density in a native cellular environment, providing insights into the signal-initiation process in this system that have not been revealed through the determination of ligand-binding constants obtained by more traditional methods.

As process analytical technology (PAT) moves out of the laboratory and into the plant and to the process stream itself, the question arises, "What is the best way to collect data from stream samples?" The author shows that this depends upon both the nature of the stream and the components to be measured.

The element selenium plays three distinct roles in biological processes, functioning in turn as a toxicant, a chemopreventive agent, and a heavy metal antagonist. This article discusses current research associated with each role, and how ICP-MS can be employed to better understand and utilize selenium's properties.

GFS Chemicals uses its high purity acids to manufacture salts and solutions used in trace metal analysis.

Guest author John Coates describes a new, compact handheld Raman instrument.

Most of the 2.2 billion dollars increase in the 2006 federal research and development budget will go toward defense weapons development and human space exploration technologies, according to the American Association for the Advancement of Science.

Chemists use spectroscopy to understand the unusual chemical behavior of water at the molecular level.

This report demonstrates that it is possible to meet and exceed EPA "statement of work" requirements using ICP-MS.

Since 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.

Some types of spectroscopy work better if the intensity of the light source increases and decreases in a regular pattern. Such a varying signal is called modulated, and here, the author explores the devices that perform this function.

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.

The basic characteristics of variable filter array (VFA) spectrometers, both near- and mid-infrared, make them well suited for routine infrared analysis applications outside and inside the laboratory. The performance of this spectrometer is discussed here.

The second installment of this two-part series illustrates further technical principles and applications of the most common mass analyzers used in bioanalytical laboratories today, as well as novel techniques and mass analyzer designs. Examples are based upon the authors' research in small molecule applications.

This study describes the development of a robust, high-throughput analytical method for the determination of 18 elements (15 trace elements and three electrolytes) in blood and serum samples using a collision/reaction cell quadrupole ICP-MS system.