LC*GC

December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1995 - 1996

COLUMNS

• SAMPLE PREP PERSPECTIVES
  "Just-Enough" Sample Preparation: A Proven Trend in Sample Analysis
  Ronald E. Majors
  By achieving selectivity in other portions of the analytical cycle, we can lower the burden on sample preparation.
  
• LC TROUBLESHOOTING
  Avoiding Refractive Index Detector Problems
  John W. Dolan
  A description of how refractive index detectors work and some good practices to get the most out of this powerful detector
  
• BIOTECHNOLOGY TODAY
  The Use of Light-Scattering Detection with SEC and HPLC for Protein and Antibody Studies, Part II: Examples and Comparison to Mass Spectrometry
  Simion Kreimer, John Champagne, Anurag S. Rathore, and Ira S. Krull
  Detailed examples of light-scattering techniques are presented as well as how their performance compares to MS and other methods.
  
• THE ESSENTIALS
  Ion-Trap and Time-of-Flight Mass Analyzers
  A review of the principles of these analyzers and their relative advantages and disadvantages over other mass analyzer types
  

ARTICLES

• Maximizing Robustness and Throughput in Liquid Chromatography by Using Pressure-Controlled Operation
  Matthias Verstraeten, Ken Broeckhoven, Klaus Witt, Konstantin Choikhet, Monika Dittmann, and Gert Desmet
  Analysis time can be reduced 10-30% by switching from constant-flow-rate mode to a constant-pressure gradient-elution mode.
  
• Elevated Temperatures in Liquid Chromatography, Part III: A Closer Look at the van 't Hoff Equation
  David S. Jensen, Thorsten Teutenberg, Jody Clark, and Matthew R. Linford
  An exploration of the usefulness and relevance of the van 't Hoff equation using various examples from the literature
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Calendar
• Short Courses
• Info for Authors
• Ad Index

COLUMNS

• COLUMN WATCH
  Revival of Capillary Electrophoresis Techniques in the Pharmaceutical Industry
  Cari Sänger-van de Griend
  A look at what influences the use of CE in the pharma industry.
  
• LC TROUBLESHOOTING
  Evaluation of an LC Method
  Fatos Osmani and John W. Dolan
  How can we tell if an LC method is working properly?
  
• GC CONNECTIONS
  Gases Q & A
  John V. Hinshaw
  A number of frequently asked questions about gases and their delivery to a gas chromatography instrument are addressed.
  
• HISTORY OF CHROMATOGRAPHY
  Phyllis Brown: A Story of Serendipity, Perseverance, Vision, and Chromatography
  Karyn M. Usher
  A profile of a pioneer in the use of HPLC in biochemistry.
  
• THE ESSENTIALS
  Quadrupole Mass Analyzers
  We explain the working principles of the most popular of all mass analyzing devices.
  

ARTICLES

• Assay for Parts-Per-Million Levels of Azide in Drug Substances
  P.W. Wrezel, M.R. Lutz, Jr., I. Likhotvorik, and J. Cao
  A simple and practical assay for azide using chemical derivatization and high performance liquid chromatography.
  
• Elevated Temperatures in Liquid Chromatography, Part II: Basic Thermodynamics of Elevated-Temperature LC, Including the van 't Hoff Relationship
  David S. Jensen, Thorsten Teutenberg, Jody Clark, and Matthew R. Linford
  The authors explore some basic thermodynamic relationships.
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Ad Index

COLUMNS

• COLUMN WATCH
  Ultrahigh-Efficiency Protein Separations with Submicrometer Silica Using Slip Flow
  Benjamin J. Rogers, Bingchuan Wei, and Mary J. Wirth
  An explanation of how "slip flow" works and the presentation of a practical example using this concept.
  
• LC TROUBLESHOOTING
  The Role of the Injection Solvent
  Bandar Alsehli and John W. Dolan
  A closer look at how the solvent chosen for injection can affect the appearance of chromatographic peaks.
  
• GC CONNECTIONS
  Solid-Phase Microextraction
  John V. Hinshaw
  SPME decouples sampling from matrix effects that would distort the apparent sample composition or disturb the chromatographic separation. It is also easy to use and reduces solvent consumption.
  
• THE ESSENTIALS
  Introduction to Preparative HPLC
  An overview of the principles and equipment required for scaling analytical separations to the preparative scale and considerations for the scale of analyte required.
  

ARTICLE

• Determination of Pesticides in Red Wine by QuEChERS Extraction, Rapid Mini-Cartridge Cleanup, and LC-MS-MS Detection
  Xiaoyan Wang and Michael J. Telepchak
  Sample preparation in this study involved QuEChERS extraction followed by a filter-based cleanup method that is easier and faster than dispersive solid-phase extraction.
  

DEPARTMENTS

• Peaks of Interest
• Product Showcase
• Ad Index

COLUMNS

• COLUMN WATCH
  Highlights of HPLC 2012
  Ronald E. Majors
  A review of the trends at this year's symposium, including discussions of column technology, sample preparation, and detector usage.
  
• LC TROUBLESHOOTING
  Readers' Questions
  John W. Dolan
  Questions from the e-mail bag are considered this month.
  
• MS - THE PRACTICAL ART
  Multidimensional LC Approaches for Intact Protein Biopharmaceutical Characterization
  Sean M. McCarthy
  Multidimensional LC can automate sample preparation and provide a convenient way to analyze a sample with complementary columns.
  
• BIOTECHNOLOGY TODAY
  The Use of Light-Scattering Detection with SEC and HPLC for Protein and Antibody Studies, Part I: Background, Theory, and Potential Uses
  Simion Kreimer, Ira S. Krull, and Anurag S. Rathore
  Light-scattering detection: the theory and the advantages
  
• THE ESSENTIALS
  A Short Introduction to Multidimensional GC
  Achieving efficient analyte transfer between columns is critical to gaining the benefits of multidimensional GC.
  

ARTICLES

• Professor Walter Goodrich Jennings: A Remembrance
  Phil Stremple
  
• Elevated Temperatures in Liquid Chromatography, Part I: Benefits and Practical Considerations
  David S. Jensen, Thorsten Teutenberg, Jody Clark, and Matthew R. Linford
  Benefits of using elevated-temperature separations and some practical considerations for implementing this approach
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Ad Index

COLUMNS

• SAMPLE PREP PERSPECTIVES
  Supported Liquid Extraction: The Best-Kept Secret in Sample Preparation
  Ronald E. Majors
  An alternative approach to liquid-liquid extraction is explored.
  
• LC TROUBLESHOOTING
  Questions from Afar
  John W. Dolan
  Problems with retention-time drift, temperature control, and broad peaks from a new column are discussed.
  
• MS - THE PRACTICAL ART
  Mass Spectrometry: The Premier Analytical Tool for DMPK Scientists in a Drug Discovery Environment
  Walter Korfmacher
  An overview of applications of various types of MS systems in drug discovery efforts, including in vitro and in vivo screening assays.
  
• THE ESSENTIALS
  Understanding Ion-Exchange Chromatography
  An overview of the separation principles, columns, and equipment.
  

Special Section
CELEBRATING 30 YEARS OF LCGC

• Analysis of the State of the Art: Sample Preparation
  Mary Ellen P. McNally
  
• Analysis of the State of the Art: GC Columns
  Laura Bush
  
• Analysis of the State of the Art: GC Instrumentation
  Laura Bush
  
• Analysis of the State of the Art: LC Columns
  Laura Bush
  
• Analysis of the State of the Art: LC Instrumentation
  Laura Bush
  

DEPARTMENTS

• From the Publisher
• From the Editor
• Guest Editorial
• Peaks of Interest
• Ad Index

COLUMNS

• COLUMN WATCH
  The State of the Art and Future Trends of Size-Exclusion Chromatography Packings and Columns
  Howard G. Barth and Greg D. Saunders
  A comprehensive review of standard and specialty SEC columns, including up-to-date charts and advice on how to choose
  
• LC TROUBLESHOOTING
  Troubleshooting Basics, Part IV: Peak Shape Problems
  John W. Dolan
  In a well-behaved method, changes in peak shape should occur gradually over hundreds or thousands of samples. Tailing of one or a few peaks usually points to a problem.
  
• GC CONNECTIONS
  A GC Troubleshooter's Toolkit
  John V. Hinshaw
  Many tools gas chromatographers keep on hand are specialized, but others can be found in the toolkits of plumbers and carpenters.
  
• HISTORY OF CHROMATOGRAPHY
  50 Years in Chromatography and Sorption Techniques: A Look from the East
  Vadim Davankov
  In both East and West, new ideas have often met resistance.
  
• THE ESSENTIALS
  Gradient HPLC for Reversed-Phase Separations
  Gradients can provide improved peak shape, higher efficiency, and sometimes altered selectivity and improved resolution.
  

ARTICLE

• Facts and Legends About Columns Packed with Sub-3-µm Core-Shell Particles
  Fabrice Gritti and Georges Guiochon
  Detailed study results challenge common beliefs about the mechanisms behind the excellent performance of core-shell particles.
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Ad Index

COLUMNS

• COLUMN WATCH
  Stationary Phases for Modern Thin-Layer Chromatography
  Fred Rabel and Joseph Sherma
  Advantages of the planar, off-line format of TLC relative to on-line column HPLC, the steps in TLC analyses, and future prospects of TLC are discussed.
  
• LC TROUBLESHOOTING
  When Should an Internal Standard Be Used?
  John W. Dolan
  Will an internal standard always improve data quality?
  
• MS - THE PRACTICAL ART
  New Frontiers for Mass Spectrometry in Lipidomics, Part II
  Giuseppe Astarita
  Mass spectrometry analysis of lipids in complex matrices is revolutionizing the way lipid research is conducted.
  
• INNOVATIONS IN HPLC
  The Spectro-Electro Array: A Novel Approach for the Measurement of Secondary Metabolites in Botanicals, Supplements, and Beverages
  P.A. Ullucci, B.A. Bailey, D.H. Thomas, and I.N. Acworth
  HPLC with diode-array and electrochemical-array detection overcomes sensitivity and specificity limitations in natural products analysis.
  
• THE ESSENTIALS
  Performance Characteristics Measured in Method Validation
  Analytical method validation is the process of demonstrating that a method does what it is intended to do.
  

ARTICLE

• Capillary Electrophoresis-Mass Spectrometry for the Analysis of Biopharmaceuticals
  Rob Haselberg, Gerhardus J. de Jong, and Govert W. Somsen
  CE-MS using noncovalent coated capillaries provides advantages for purity and stability analysis of biopharmaceutical
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Ad Index

COLUMNS

• COLUMN WATCH
  New Chromatography Columns and Accessories at Pittcon 2012, Part II
  Ronald E. Majors
  What you need to know about gas chromatography columns, thinlayer chromatography plates, sample preparation products, as well as chromatography and sample preparation accessories (including small benchtop instruments) unveiled at Pittcon this year
  
• LC TROUBLESHOOTING
  Extra Chromatographic Peaks - A Case Study
  John W. Dolan
  What do you do when an unexpected peak appears?
  
• GC CONNECTIONS
  New Gas Chromatography Products 2012
  John V. Hinshaw
  A review of gas chromatography instruments and accessories presented at Pittcon 2012
  
• BIOTECHNOLOGY TODAY
  Bioanalytical Tools for the Characterization of Biologics and Biosimilars
  András Guttman
  LC-MS and CE-MS are the go-to techniques for characterizing biologics, but often help is needed from a range of other methods.
  
• THE ESSENTIALS
  Column Characterization Databases
  Can databases of column characteristics be used to help with HPLC column selection ahead of method development?
  

ARTICLE

• Ultratrace Quantitative Analysis of Catalyst Poisoners Using a Dedicated GC-MS Analyzer
  Kevin M. Van Geem, Jeroen Ongenae, Jean-Louis Brix,Joeri Vercammen, and Guy B. Marin
  Here is an overview of the main characteristics and performance of a new gas chromatography-mass spectrometry (GC-MS) analyzer that was recently developed.
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Ad Index

COLUMNS

• COLUMN WATCH
  New Chromatography Columns and Accessories at Pittcon 2012, Part I
  Ronald E. Majors
  A review of columns unveiled at Pittcon this year, including all modes of HPLC, UHPLC, and liquid-phase separations.
  
• LC TROUBLESHOOTING
  Retention Time Changes
  John W. Dolan and Justin Chow
  What happens when the same method gives different retention times on different instruments?
  
• INNOVATIONS IN HPLC
  HPLC Systems and Components Introduced at Pittcon 2012: A Brief Review
  Michael Swartz
  Highlights of some of the new HPLC and related technology showcased both before and at this year's conference
  
• HISTORY OF CHROMATOGRAPHY
  Efficient HPLC Method Development and Personal Reflections
  Lloyd R. Snyder
  A pioneer in high performance liquid chromatography reflects on his career and how "enlightened trial-and-error" can reduce the effort involved in method development.
  
• THE ESSENTIALS
  Electron Ionization for GC-MS
  A look at the process of forming radical cations for analysis in GC-MS and the role of various ion source components
  

ARTICLE

• A Practical Method for Trace-Level Analysis of Chlorinated Organic Pesticides by Gas Chromatography-Mass Spectrometry
  K. Gras, R. Gras, and J.Luong
  A review of a gas chromatographic procedure developed for the direct measurement of trace levels of lindane, aldrin, heptachlor epoxide, dieldrin, o,p-DDD, and dichlorodiphenyltrichloroethane (DDT)
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Ad Index

COLUMNS

• SAMPLE PREP PERSPECTIVES
  Theoretical Concepts and Applications of Turbulent Flow Chromatography
  Joseph L. Herman and Tony Edge
  A useful method for online sample cleanup of biological matrices.
  
• LC TROUBLESHOOTING
  Why Does an Improvement Make Things Worse?
  John W. Dolan
  Column changes may cause unexpected problems.
  
• GC CONNECTIONS
  How to Restore an Idle GC Column to Operating Condition
  John V. Hinshaw
  For smooth operation, follow this step-by-step guide.
  
• THE ESSENTIALS
  Developing High-Throughput Separations in Capillary GC
  Strategies for reducing analysis time in capillary gas chromatography
  

ARTICLES

• The 2012 LCGC Awards
  Laura Bush
  The winners of LCGC's sixth annual awards are highlighted.
  
• Coupling Supercritical Fluid Chromatography with Evaporative Light Scattering Detection: A Study of the Relevant Parameters Ruling Response
  E. Lesellier, C. West, T. Bizet, A. Valarch‚, and M. Dreux
  The mobile-phase flow rate and the amount of modifier mixed with carbon dioxide are the main parameters affecting peak area.
  
• Speciation Analysis of Mercury in Sediments Using HPLC Hyphenated to Vapor Generation Atomic Fluorescence Spectrometry Following Microwave-Assisted Extraction
  Geng Leng, Li Feng, Shao-Bo Li, Ping Yang, and De-Zhong Dan
  This validated method is faster and simpler than other approaches, and detection limits are comparable.
  

DEPARTMENTS

• News Spectrum
• Product Resources
• Calendar
• Short Courses
• Ad Index

COLUMNS

• COLUMN WATCH
  It's All About Selectivity
  Diane Turner
  Learn how to use selectivity throughout the sample analysis cycle, from the sampling stage through data analysis and report generation.
  
• LC TROUBLESHOOTING
  A Case of Sporadic LC Assay Results
  Michael W. Dong and Kelly Louie
  A mysterious autosampler problem is solved.
  
• MS - THE PRACTICAL ART
  New Frontiers for Mass Spectrometry in Lipidomics, Part I
  Giuseppe Astarita
  Part I of this series explains how lipids analysis has evolved.
  
• HISTORY OF CHROMATOGRAPHY
  Harold McNair: An Innovator in Gas Chromatography Research and Teaching
  Kevin Schug
  An interview with Harold McNair reveals his greatest accomplishments and proudest moments.
  
• THE ESSENTIALS
  Electrospray Ionization for Mass Spectrometry
  The secret to electrospray ionization lies in three key steps.
  

ARTICLES

• Rapid, Efficient Quantification of Water in Solvents and Solvents in Water Using an Ionic Liquid-Based GC Column
  Dilani A. Jayawardhana, Ross M. Woods, Ying Zhang, ChunleiWang, and Daniel W. Armstrong
  An ionic liquid-based capillary gas chromatography method is shown effective for determining the water content in liquid samples.
  
• Book Review: Introduction to Modern Liquid Chromatography, 3rd Edition
  Victoria L. McGuffin

DEPARTMENTS

• From the Editor
• Peaks of Interest
• Product Showcase
• Calendar
• Short Courses
• Ad Index

COLUMNS

• COLUMN WATCH
  Current Trends in HPLC Column Usage
  Ronald E. Majors
  The results of a recent survey on high performance liquid chromatography (HPLC) columns shows some interesting changes.
  
• LC TROUBLESHOOTING
  LC Trouble Everywhere
  John W. Dolan
  This month, we look at calculating injection volume, choosing a wash solvent, and handling doubts about reference standard purity.
  
• GC CONNECTIONS
  Headspace Sampling, Part II: Instrumentation
  John V. Hinshaw
  Headspace autosamplers and sampling methods are more complex than their liquid autosampler counterparts. Chromatographers need to manage a rich set of choices to obtain the best results.
  
• BIOTECHNOLOGY TODAY
  Analytical Tools for Enabling Process Analytical Technology Applications in Biotechnology
  Anurag S. Rathore, Ira S.Krull, and Rakesh Mendhe
  For PAT, you need to choose the right analytical methods. Here's how.
  
• THE ESSENTIALS
  HILIC
  Tony Taylor
  This new column explains the essentials of key methods in separation science. This month: hydrophilic interaction chromatography.
  

ARTICLE

• Static Headspace GC-MS Detection of Residual Solvents - A Possible Simultaneous Identification and Quantitation Method
  Alyssa J. Andrews-Ashley, Jennifer L. Belsky, Heather R. Joyce, Chunhua Pan, Horacio Pappa, and Samir Z. Wahab
  A new procedure is proposed that provides identity parameters for headspace-applicable residual solvent Class 1 and Class 2 compounds addressed in the current US Pharmacopeia <467> method.
  

DEPARTMENTS

• Peaks of Interest
• Product Resources
• Calendar
• Ad Index