Liquid Chromatography (LC/HPLC)

A simple, rapid, and sensitive method is presented for clinical measurements of ascorbic acid and malondialdehyde in human serum.

How the use of peptide standards can indicate control as well as provide guidelines for method development.

A look at ways to get more out of your detector.

The second part of a two-part series examining new column introductions at Pittcon 2004.

This article describes the optimum performance laminar chromatography technique and gives a brief account of recent applications in which it has been used.

In the first of a two-part series, Ron Majors examines new column introductions at Pittcon with special attention to high performance liquid chromatography columns and packings for reversed-, normal- and bonded-phase; ion exchange; ion and size-exclusion chromatography. He also considers speciality HPLC columns.

Following on from a previous instalment, this month's column assesses evaporative light-scattering detection as a complementary detection mode and builds upon the previous discussion in terms of detector applications.

In this month's column, the authors present a relatively simple method for selecting the appropriate curve-fitting function and thus ensure that the requirements of current guidelines can be met.

This month'ss "Column Watch" is the first of a two-part series that examines new column introductions at Pittcon 2004.

Evaporative light-scattering detection offers a complementary detection mode that can detect nearly all eluted compounds in either isocratic or gradient conditions.

Which curve-fitting function should be used?

This article establishes the estimation of the uncertainty associated with the chromatographic determination of biogenic amines.

Peaks that are too broad can mean that analysts are not using their LC columns very efficiently. In this month's column, John Dolan describes how to determine if peaks are broader than they should be and highlights some of the common system-related causes of peak broadening.

In the welcome return of this column, Bob McDowall revisits the evolving topic of 21 CFR 11 compliance, as it applies to chromatographers. He examines the FDA's activities in 2003 and outlines the current status of its regulations over, and guidance for, electronic records issues.

In this article the authors report on a combinatorial natural product discovery methodology that uses a viral vector system to transfer secondary metabolite-related enzymes from C. roseus to tobacco cell cultures. Using high-resolution separation techniques, including HPLC, CE and MS, they describe the analysis of secondary metabolite patterns.

This month's column examines several possible causes of peak splitting and presents some guidelines for isolating the problem source.

Phytosterols and stanols (hydrogenated phytosterols) are naturally occurring substances?

The current concern over acrylamide levels in food has unexpectedly brought amino acid analysis to the forefront . . .

Two solutions to the problem of obtaining quantitative information about protein expression are to couple two or more chromatographic modes to increase resolution and to use affinity selection techniques.

Tim Wehr looks at the requirements of multidimensional LC and provides examples of some systems used in proteomics.

Tim Wehr looks at the use of fast LC}MS for high-throughput analysis of pharmaceutical compounds.

This month Tim Wehr discusses traditional approaches to protein characterization.

The authors investigated the analytical capabilities of quadrupole, time-of-flight, and Fourier transform mass analyzers for liquid chromatography electrospray mass spectrometry (LC-MS) applications.

How can you avoid phase collapse when 5% organic solvent is too strong?

This month's "Column Watch" describes moving bed chromatography and how the concept is realized in the form of simulated moving bed chromatography. Also included is an inside look at instrumentation, method development, and applications for industrial purifications.

How can internal LC surfaces be made less reactive?

This installment of "Milestones in Chromatography" looks at two major international meetings held in Las Vegas, Nevada, and Seattle, Washington, that were pivotal in the early development of HPLC.

This month's "Directions in Discovery" gives a brief overview of turbulent- flow liquid chromatography, a technique for fast separations. Two examples demonstrate the use of the technology for high-throughput bioanalytical separations in drug discovery.

Given the increasing number of chiral samples and the time constraints under which chromatographers work, choosing an appropriate chiral stationary phase for the resolution of enantiomers can be challenging. In this article, the authors describe a screening approach for chiral HPLC method development.

Stainless steel is inert – or is it?