**LC*GC**

Volume 28, Number 2, February 2010

**LC*GC February 2010 Table of Contents**

SAMPLE PREP PERSPECTIVES
Electromembrane Extraction: The Use of Electrical Potential for Isolation of Charged Substances from Biological Matrices
Astrid Gjelstad
This minireview of electromembrane extraction demonstrates how the combination of an electroextraction with hollow-fiber liquid-phase microextraction can lead to a selective, rapid new method.
LC TROUBLESHOOTING
Column Diameter, Linear Velocity, and Column Efficiency
John W. Dolan
John Dolan examines some questions he recently received concerning the changes that took place in the 2009 edition of the United States Pharmacopoeia.
MS—THE PRACTICAL ART
The Nature and Utility of Mass Spectra
Michael P. Balogh
This month’s installment addresses some elementary aspects of the mass spectrum, the tools employed by the experienced practitioner, and advances being made into identifying unknowns.
HISTORY OF CHROMATOGRAPHY
A History of Gas Chromatography: My Early Experiences
Harold McNair
Industry veteran and 2009 LCGC Lifetime Achievement Award winner Harold McNair discusses the history of temperature programming in the field of GC.

Multiple Dimensions of Separations: SPME with GC×GC and GC×GC–TOF-MS
Nicholas H. Snow, Jerianne Sinex, and Mandelle Danser
The combination of SPME with GC×GC and GC×GC–TOF-MS is discussed using mixtures of solvents as example analytes.

Volume 28, Number 1, January 2010

COLUMN WATCH
Hydrogen as a Carrier Gas for GC and GC–MS
James Heseltine
Guest columnist James Heseltine discusses hydrogen as an effective replacement for helium in many GC and GC–MS applications.
LC TROUBLESHOOTING
Too Little or Too Much
John W. Dolan
John Dolan discusses an all too common problem: What to do when a peak is too small or too large.
GC CONNECTIONS
Upgrading Gas Chromatography
John V. Hinshaw
This month’s “GC Connections” explores the issues that can arise when deciding to upgrade or replace GC technologies.
INNOVATIONS IN HPLC
HPLC: Continuing to Answer Challenges to Food and Drug Safety
Michael Swartz
Three analysis challenges have been receiving a great deal of attention: the water we drink, the food we eat, and the drugs we take. Michael Swartz discusses the use of HPLC to address these threats to health and safety.

A Generic Headspace GC Method for Residual Solvents in Pharmaceuticals: Benefits, Rationale, and Adaptations for New Chemical Entities
Lulu Dai, Amanda C. Quiroga, Ke Zhang, Heather B. Runes, Derrick T. Yazzie, Kavita Mistry, Nik P. Chetwyn, and Michael W. Dong
The authors describe a generic static headspace gas chromatographic (HSGC) method for determining common residual solvents in pharmaceuticals.