Columns | Column: Atomic Perspectives

Here are nine suggestions for improving this valuable technique.

Most analytical measurements performed by either inductively coupled plasma–optical emission spectrometry (ICP-OES) or ICP–mass spectrometry (MS) require accuracy and precision, which are essential for obtaining correct answers. However, all modern ICP-OES and ICP-MS instruments have the ability to perform semiquantitative analyses. This seems strange since accuracy is important, but semiquantitative analysis does have a role in analytical measurements. This article will explore why semiquantitative analysis is important and will look at various ways it can be performed and implemented.

The USP proposes the use of analytical techniques capable of measuring impurities at the specified limits with optimal selectivity, sensitivity, simplicity, and robustness.

ICP-MS is powerful technique capable of measuring very low levels in a wide variety of sample types, limited only by cleanliness and the presence of interences. This article will examine the types of interferences that are encountered and various ways of dealing with them using a quadrupole ICP-MS instrument: mathematical correction equations, matrix removal, and cell-based ICP-MS. The strengths and limitations of each method will be discussed.

While viewed as a mature technology, atomic absorption is still an attractive choice, particularly in the area of food safety.

Guest authors Steve Wilbur and Ed McCurdy discuss the role of qualifier ions in ICP-MS research in this month's installment of "Atomic Perspectives."

This article is a follow-up to an earlier "Atomic Perspectives" column on the spectral lines of hydrogen (1).

Speciation analysis by LC-ICP-MS has been growing rapidly in popularity and application over the past several years. Not only have people begun looking at different elements and species, but there has also been an increase in the variety of matrices that speciation analysis is being performed on.

One of the most difficult tasks in any laboratory is the validation and assurance of all data being reported. Whether or not this is being mandated by a regulating agency, it is imperative that the quality of data from any analysis be controlled. How do the laboratory workers ensure the quality of their reported analyses and how do they demonstrate this quality?

Volker Thomsen takes a look at the impact that the discovery of X-rays by Wilhelm Röntgen in 1895 has had on the world.

Guest columnist Steven Wilbur discusses the elemental nature of ICP-MS and its strength as a universal quantifier, an aspect of the technique he believes has not received enough attention.

The authors discuss speciation analysis methods that enable scientists to identify and measure the quantities of one or more individual chemical species in a sample.

A short history of the early scientific developments related to the optical emission lines of hydrogen is presented. These were crucial to the development of the quantum theory. Balmer's empirical formula was an important milestone. Rydberg and others provided additional work, especially for higher atomic numbers. However, it remained for Bohr to provide the physical reasoning.

While inductively coupled plasma-mass spectrometry (ICP-MS) is capable of part-per-quadrillion (ppq) detection limits under ideal conditions, most applications do not require this level of sensitivity and do not justify the cost associated with achieving it. Practical sensitivity in ICP-MS is determined not by instrument signal-to-noise ratio, but rather by controlling interferences and matrix effects in real samples. Understanding the sources of these effects and their management is critical in determining the most practical way to achieve specific data quality objectives.

Speciation analysis has grown rapidly and has expanded to a variety of markets, including environmental, clinical, food, nutraceutical, and bioanalytical. This growth has resulted from the realization that knowing the total amount of an element does not always provide adequate information for assessing health and environmental effects, but knowing which form of the element is present presents a much more comprehensive picture.

Simple, fast, and reliable on-site hydraulic oil analysis should be an integral part of any preventative maintenance program. Since the majority of machine failures are contamination related, it is important to analyze the hydraulic fluid to monitor equipment condition and identify machine wear. Significant cost savings can result from early identification of machine failure, oil quality, handling and other problems. Oil analysis can detect changes in oil quality, contamination, wear and chemical differences. Benefits of this information include prolonged equipment life, reduced equipment downtime, and reduced overall maintenance costs. In addition, plants can increase intervals between oil changes, thus reducing waste oil, maintenance, and oil purchase costs.

The RoHS/WEEE directive requires the electronics industry to certify that products comply with maximum concentration amounts of particular elements and compounds (Cr VI, Pb, Cd, Hg, Br PBB/PBDE) by July 2006. Instrumentation must be developed to perform the certification.