How Close is Close Enough? Accuracy and Precision
September 1st 2006September 2006. The accuracy and precision of results in gas chromatography and other analytical techniques are highly dependent upon the sample and its preparation, the instrumentation, accessories, and operating conditions, as well as on operator skill and experience. For these reasons, accuracy and precision for a specific methodology can be expected to vary from one laboratory or operator to another. This month, we look at statistical analysis as a diagnostic tool.
What's Happening to My Column?
September 1st 2006John Dolan addresses two column-related problems reported by readers - the first deals with a column that takes several injections to "settle down" for each batch of samples while the second problem relates to short column life due to early fouling of the column.
Top-Down versus Bottom-Up Approaches in Proteomics
September 1st 2006September 2006. Top-down and bottom-up are alternative strategies for protein identification and characterization by mass spectrometry. How do they fit into the world of proteomics? What are their implications for separation technology? These questions are addressed in this installment of "Directions in Discovery."
Market Profile: Fast Liquid Chromatography
September 1st 2006The market for high performance liquid chromatography (HPLC) continues to be one of the most dynamic markets of the analytical instruments industry. A few years ago, the HPLC market began showing signs of maturity with little product innovation and slower growth rates. Although innovations in mass spectrometry (MS) helped to fuel growth, HPLC was an afterthought and considered to be a mere inlet to MS. However, the recent development of fast liquid chromatography (LC) systems is energizing the HPLC market.
Analytical Limbo: How Low Can You Go?
September 1st 2006September 2006. In analytical chemistry, the continual quest for enhanced sensitivity and specificity - in gas chromatography (GC), this can be equated to separation power - remain the common goal in the development of new analytical methodologies. Today, GC is still the most widely used method for the analysis of volatile and semivolatile organic compounds. When coupled with the right choice of detector for the specific application, a wide linearity range and low limit of detection (LOD) can be met. For GC analyses, many approaches can be used to achieve greater sensitivity and lower LOD. They can be classified broadly into four categories: improved sampling (sample preparation) strategies; sample introduction methods; improved chromatographic performance; and alternative (selective–sensitive) detection transducers. This article provides an up-to-date review of existing and emerging chromatographic innovations, based upon these four strategies, that will improve sensitivity and detection limits of trace..