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The materials examined by mass spectrometrists may have hundreds to thousands of unique components in a wide concentration range. The spectra are very complex; to even a trained eye, two [...]

The contact between food or pharmaceuticals and the packaging that contains them presents a fascinating opportunity for creative chemistry. It also creates a test for analysts. A 2007 installment of [...]

Mass spectrometry (MS) has been a cornerstone technology of the chemical industries including petroleum research and related commercial product manufacturing in polymers. The American Society for Mass Spectrometry (ASMS) will [...]

The phenomenal growth of mass spectrometry (MS) as a diverse analytical tool, especially when viewed from my occasional role teaching and participating in liquid chromatography-mass spectrometry (LC-MS) courses, has underscored [...]

In mass spectrometry (MS) the laser, together with electrospray ionization, has become an essential tool to further our analytical pursuits in the sciences. The 50th anniversary of its invention marks [...]

In mass spectrometry, the electrospray ionization technique quickly earned its place among the primary analytical tools. Yet it is not always the best tool for the job. Matrix effects and [...]

In an astonishingly short time, mass spectrometer manufacturers have developed highly capable, compact instruments that integrate well with advanced liquid chromatography (LC) systems. Driving that achievement are breakthroughs in technology [...]

For many the need to achieve an end result makes it easy to overestimate how much we know as we plunge into an analytical pursuit n just as it is [...]

"When one man has reduced a fact of the imagination to be a fact of his understanding, I foresee that all men will at length establish their lives on that [...]

I first discovered the promised potential of lab-on-a-chip (LOC) technology at a Gordon Conference in the mid-1970s, when gas chromatography (GC) columns were reported on glass microscope slides. Since then, [...]

In 1997, in an article that appeared in what then was LCGC International (now LCGC Europe), I departed from my usual technical writing, which up to then had been primarily [...]

The oxymoron in the title illustrates a predicament in analytical practice. Since the early 1990s, we have witnessed great strides in mass spectrometry (MS), improvements that bring sophisticated capabilities to [...]

We will restore science to its rightful place, and wield technology's wonders to raise health care's quality and lower its cost. We will harness the sun and the winds and [...]

In this work, we demonstrate the utility of ultra performance liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry (UPLC-APPI-MS/MS) for high-sensitivity and high-throughput analysis of United States Environmental Protection Agency (U.S. EPA) 16 priority pollutants polycyclic aromatic hydrocarbons (PAHs). Analyses were performed on a Waters Acquity-TQD equipped with Syagen's PhotoMate APPI source. All 16 PAHs were analyzed on column in approximately 3.5 min with excellent chromatographic separation for all PAH isomers and with low picogram detection limits on column for all analytes using chlorobenzene as a dopant. Dynamic linear ranges were evaluated and found to cover at least 3-4 orders of magnitude. In comparison with the existing U.S. EPA methods, this approach improves instrument sample throughput by at least 10-fold.

This issue completes the multi-part MS primer with a list of terms derived from common usage throughout various industries and, while included with the MS Primer. is intended to stand [...]

Part III concludes the print version of our three-part series, "A Mass Spectrometry Primer, with the glossary to follow in a fourth and final installment. To recap the basis for [...]

This month's column continues with Part II of the three-part series, "A Mass Spectrometry Primer." To recap the basis for undertaking this work, technological changes that affect our knowledge, in [...]

Technological changes affecting how we access information--both in the depth of knowledge we can access and the speed--leads to some observations about electronic versus print media. First, anything committed to [...]

The matter of perfluorinated compounds (PFCs) came to focus at the United States Environmental Protection Agency (EPA) some eight years ago. These fully fluorinated compounds have become the source of [...]

Every atom's mass defect is distinctive, and linear combinations of things in nature seldom overlap. For a combination of carbon, hydrogen, nitrogen, oxygen, and sulfur, every mass is unique. Our [...]

Nearly a dozen incipient technologies have appeared in recent years. Which will survive? Which will find extensive, robust usage as did electrospray ionization? Which are fated to become footnotes in [...]

"As research advances, about half of what we will teach you ... will turn out to be wrong. The problem is, we presently don't know which half." Powerful Medicines, Jerry [...]

Kina and Fiehn come to a striking conclusion in a recent article based upon examination of 1.6 million formulas: "[H]igh mass accuracy (1 ppm) and high resolving power alone is [...]

Like musical instrumetnts, mass spectrometers abide the same constancy of physics but through complex idiosyncrasies; neither pleases everyone all the time ********** MS--The Practical Art, this column's running rubric, reflects [...]

This year marks the 250th anniversary of what many consider to be the first major contribution to the English language: Samuel Johnson's dictionary (1755). Johnson was contracted by a publisher's [...]

Liquid chromatography-mass spectrometry (LC-MS) has been increasingly indispensable in most analytical pursuits. Such acceptance would not have occurred without encouraging, early academic efforts, and also the efforts of early practitioners [...]

The Centers for Disease Control and Prevention (CDC) estimates that each year in the United States, 76 million people get sick, 325,000 are hospitalized, and 5000 die from food-related illnesses. [...]

'Mass spectrometry (MS) is widely appreciated as a powerful analytical method, characterized by high sensitivity and high information content, that can be used for both the qualitative and quantitative analysis [...]

"Mass spectrometry (MS) is widely appreciated as a powerful analytical method, characterized by high sensitivity and high information content, that can be used for both the qualitative and quantitative analysis [...]

In this initial installment of 'MS--The Practical Art,' a new series of columns is introduced that investigates various aspects of mass spectrometry (MS) from the perspective of some leading practitioners. [...]

Informatics and data management was an obvious and intuitive topic to include in last year's Conference on Small Molecule Science (www.CoSMoScience.org). Indeed, the favorable response of attendees made it clear [...]

Drug discovery generally is thought of as creation of a compound that possesses the potential to become a useful therapeutic. Successful discovery rests on a number of elements, one of [...]

This article provides an overview of several recently developed technologies that will improve the utility and performance of mass spectrometers in a number of applications. The discussion includes photoionization, several […]

In this initial installment of "MS--The Practical Art," a new series of columns is introduced that investigates various aspects of mass spectrometry (MS) from the perspective of some leading practitioners. [...]

A mass spectrometer's resolution and mass accuracy are the primary considerations for determining whether an instrument suits its intended purpose. Unlike UV and other chromatographic detectors that provide inferential data, [...]

Few skilled or artful pursuits flourish without careful preparation. If you ever took tennis, sailing, or violin lessons, you know how hard your teacher worked to convey the notion that […]

The Practical Art This month's "MS--The Practical Art" provides an overview of several recently developed technologies that will improve the utility and performance of mass spectrometers in a number of [...]

A mass spectrometer's resolution and mass accuracy are the primary considerations for determining whether an instrument suits its intended purpose. Unlike UV and other chromatographic detectors that provide inferential data, […]

This column marks the midpoint in our five-part series, an appropriate time to recap the previous topics and thank all of you who have commented on them. The first topic [...]

Achieving greater throughput while increasing informational content figures significantly in most small-molecule practices that lead to medicinally important compounds. Various mechanical increases in productivity, improved software information flow and data [...]

A mass spectrometer's resolution and mass accuracy are the primary considerations for determining whether an instrument suits its intended purpose. Unlike UV and other chromatographic detectors that provide inferential data, [...]

The spread of liquid chromatography-mass spectrometry as an analytical tool during the past decade has promoted efforts to better accommodate applications. The physical realm of the atmospheric ionization source--materials, gas, […]

The spread of liquid chromatography--mass spectrometry as an analytical tool during the past decade has promoted efforts to better accommodate applications. The physical realm of the atmospheric ionization source--materials, gas, [...]

We have developed a fully automated LC/MS method development and quantification protocol targeting 52 carbamtes, thiocarbamates, and phenylureas. This is a simple LC/MS method with direct injection; no post-column derivatization was required. The method utilized the Waters Alliance HT Chromatography System and the Waters ZQ 2000 mass spectrometer. System control and data processing was by MassLynx 4.0 with QuanLynx Application Manager. Analyte separation was accomplished by Waters Symmetry reversed-phase [C.sub.8] column. An ammonium acetate water/acetonitrile binary gradient was used for the separation. The MS multichannel ability minimized the LC method development time with less demand on chromatographic peak resolution. Quantification results were obtained for 46 analytes out of the 52 targets. The coefficients of determination ranged from 0.886 to 0.999. The automated LC/MS protocol has sufficient sensitivity to accommodate the current EPA requirements. The limits of detection (3 times the S/N) ranged from 0.091 to 19.3 ng/mL with 50-[micro]L injection. The highly selective MS detector enabled the matrix effect to be minimized. This method was applied to local drinking water and wastewater samples. Each matrix was spiked with the 52 target analytes at 2 and 20 ng/mL The recoveries were within the EPA acceptance range.

Fast and accurate analytical methods are essential to keep pace with sample libraries produced from combinational chemistry and high-throughput biological screening. Many laboratories now use a combination of ionization techniques for the characterization of these samples, including atmospheric pressure chemical ionization (APCI), electrospray ionization (ESI), and photoionization (PI). Data are shown here from the analysis of a compound collection plate containing a variety of sample structures. ESI will normally analyze around 80% of these samples, necessitating a source change to analyze a further 10%. In this work, we have developed a new combined ESI-APCI source (ESCi) for use in on-line HPLC applications. The combined source allows alternate on-line ESI and APCI scans with polarity switching within a single analysis. The ESCi source has been designed to be a simple replacement for the existing mass spectrometer interfaces. Each ionization method is optimized independently using separate tuning parameters. Instrument electronics can readily switch between the two ionization methods and polarities within normal interscan time periods. The new source has reduced the analysis time of sample plates by eliminating the need for a source hardware change, source optimization, and repeat analyses.

The use of a new LC-MS interface (cap-EI), part of a Waters Integrity system, capable of generating EI spectra at micro flow rates is presented. The cap-EI interface relies on the production of a fine aerosol by means of a nebulizer and supported by a nitrogen jet. Sensitivity, response linearity, reproducibility, and LC compatibility of the interface were thoroughly examined using testosterone, caffeine, a mixture of antiinflammatory drugs, and 3,4-dihydroxybenzoic acid as test compounds. The interface is fully compatible with LC requirements such as high-water- and/or-buffer-content mobile phases. Reproducibility, high sensitivity in scan mode, as well, to produce library-searchable EI spectra, 2 orders of magnitude linearity, together with an intrinsic simplicity of the entire system are the key features of cap-EI interface.