All News

The authors describe how they separated and collected milligram quantities of six pyrethrin esters in pyrethrum extract and used them to create analytical reference standards for these insecticide compounds.

This installment surveys the evolution of thin-layer chromatography...

Krull and Swartz describe how chromatographers can determine peak purity and identity using new software programs.

Hinshaw looks at causes and modes of premature column failure and at practices that ensure the longest possible column life.

The authors descibe the use of CE with condensation nucleation light-scattering detection to analyze three pharmaceutical analytes. Because the compounds lack adequate UV chromophores, they require a more sensitive means of detection.

The authors compare the chromatographic properties of embedded-carbamate-group bonded phases with those of their purely alkyl counterparts.

Guest author Cameron George discusses recent advances in purge-and-trap systems that enable considerable reduction in analysis times.

The author presents an approach to screen resins for chromatographic optimization in the purification process of a protein drug substance.

This month's "LC Troubleshooting" focuses on the baseline characteristics of several common LC buffers and methods to minimize drift.

Second column of a two-part series in which Ron Majors examines trends in column introductions at Pittcon 2001. He describes GC and SFC columns, sample preparation products, and accessories.

Hinshaw explains how combining certain column dimensions and electronic pneumatic settings can produce unexpected results.

This article describes the determination of D/L-amino acid residues in peptides at microgram levels.

The first of a two-part series about LC autosamplers.

Scored layers, sequential development, modifications of the development chamber, and a careful choice of standards produce better reliability in thin-layer chromatography analysis of urine for the diagnosis of mucopolysaccharidoses. In equivocal cases, repeating the procedure and varying the solvents will improve results.

Authors Chapman and Chen describe an enantiomer analysis method development strategy that uses a family of highly sulfated cyclodextrins to resolve a diverse array of compounds.

The authors' laboratory developed and validated an HPLC method to test for residual nonoxynol-9 on stainless steel, PTFE, and acrylic substrates.

This month's column looks at reproducibility and carryover problems associated with the development of a method used to verify analyst proficiency.

The first of a two-part series in which Majors examines the trends in column introductions at Pittcon 2001. He describes HPLC columns and packings for reversed-, normal-, and bonded-phase; ion-exchange; ion; size-exclusion; and large- and preparative-scale chromatography. He also looks at specialty HPLC columns.

John Hinshaw examines inlet problems and their possible remedies.

McDowall discusses how the needs of the regulated laboratory are changing the way chromatography data systems are designed and used.

This installment of "Directions in Discovery" describes experiments performed to optimize a standard quality-control method for protein purity evaluation using reducing capillary gel electrophoresis.

Hinshaw examines the reality of GC at high speeds, taking into account the potential for rapid separations an the speed limits imposed by the practicalities of instrumentation and other considerations.

This month's column discusses the presence of sample peaks in chromatograms when only blanks are injected.

Part II of this series describes different ways electrolytes can be buffered while maintaining compatibility with indirect detection.

A single-source reference for key chromatography terms.

Ettre discusses the celebration of the 50-year anniversary of the beginning of the universal application of GC and the investigation of complex samples and natural substances.

This article examines the role that multidimensional chromatography systems will play in high-throughput proteomics.

This month's column discusses the presence of sample peaks in chromatograms when only blanks are injected -- commonly called carryover. Most carryover problems can be eliminated by performing one or more of the approaches discussed in this column.