September 4th 2024
Stockholm University scientists used liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) to characterize recycled textile products and detect harmful chemicals.
Analytical Advantages of Highly Stable Stationary Phases for Reversed-Phase LC
May 1st 2000During the past five years, many manufacturers of HPLC columns have focused on improving stationary phase stability and reproducibility. In this study, the authors use a variety of test solutes to compare the efficiency, selectivity, and hydrophobic retention mechanisms of five commercially available HPLC columns based silica, alumina, zirconia, and polystyrene cross-linked with divinylbenzene as the support.
New Chromatography Columns and Accessories at the 2000 Pittsburgh Conference, Part II
April 2nd 2000Concluding a two-part series, Ron Majors looks at the trends in the introduction of columns and column-related products at Pittcon 2000. In this second part, he describes gas chromatography and supercritical fluid chromatography columns, CE capillaries, thin-layer chromatography products, sample preparation products, and accessories for chromatography and sample preparation.
Configuring HPLC Systems for LC–MS
April 1st 2000This month's "Directions in Discovery" looks at column and mobile-phase selection as well as system components and modification. Making the right choices among these parameters will help analysts get the most out of their liquid chromatography–mass spectrometry systems.
New Chromatography Columns and Accessories at the 2000 Pittsburgh Conference, Part 1
March 1st 2000This month's column begins our annual roundup of new column technologies shown at the Pittsburgh Conference. In part I, we'll look at HPLC columns and packings for reversed-, normal-, and bonded-phase; ion-exchange; ion; size-exclusion; and large- and preparative-scale chromatography as well as specialty columns.
Starting Out Right, Part IV–Additional Variables to Control Selectivity
March 1st 2000In part III of this column series, John Dolan demonstrated that systematic variation of the solvent strength can change selectivity and retention, and changing solvent type can amplify the effect. This month, he looks at three additional parameters (pH, temperature, and column type) for adjusting selectivity.
The Effects of Inner Surface Roughness of Microbore Column Blanks on Column Performance
The efficiencies of microbore-2 columns, which are prepared from blanks that have a wide variety of inner surface roughness, drop sharply when the size of individual surface roughness features approaches the particle size of the packing material. The results suggest that two categories of packed column structure relate to the surface features and yield high and low efficiency columns. This installment of "Column Watch" discusses this conclusion in terms of the stability of an agglomerated layer of packing particles on the blank wall when subjected to shear forces during column packing.
Chromatography Data Systems, Part II: Specifying, Evaluating, and Selecting a System
February 1st 2000In the second installment of this series, the author looks at the first phase of the life cycle of a new chromatography system, bringing together a number of elements of the workflow and the functions as they are used in the laboratory.
Preparative Liquid Chromatography and the Manhattan Project
December 1st 1999This report summarizes activities performed during and after World War II at Oak Ridge National Laboratory and Iowa State University aimed at the separation of rare earths by ion-exchange chromatography on laboratory, pilot-plant, and industrial scales.
A Guide to Purchasing Used Chromatography Equipment
December 1st 1999More researchers are discovering that buying used laboratory equipment can be an effective way to reduce costs. An excellent supply of high-quality, used chromatography equipment is available on the market as a result of mergers and consolidations in biotechnology companies and downsizing in the environmental industry.
Superheated Water: A New Look at Chromatographic Eluents for Reversed-Phase HPLC
October 1st 1999The authors describe the results they've achieved by using water heated to 100–240 ºC as a liquid eluent for reversed-phase HPLC instead of an organic modifier. They point out that this alternative avoids many of the problems – toxicity, flammability, and cost – associated with organic modifiers.
Technical Note: Modifying a Standard HPLC Autosampler for On-Line Process Monitoring
September 1st 1999A simple modification of the standard HPLC autosampler flow path enables automated sampling and analysis of samples outside the autosampler unit when users cannot place the sample container inside because of size restrictions.
Fast HPLC Method Development Using Interfaced Photodiode-Array and Ion-Trap MS Detection
September 1st 1999With the goal of developing an analytical method for the fast analysis of vitamins in a complex matrix, the authors created a method that used in-line and complementary HPLC with photodiode-array and MS detection techniques.
Analysis and Fate of Surfactants in the Aquatic Environment
December 1st 3According to Analysis and Fate of Surfactants in the Aquatic Environment (Volume 40 of Wilson & Wilson's Comprehensive Analytical Chemistry), an understanding of the fate and behaviour of organic chemicals, such as surfactants?