Join us for a free two-day LECO Separation Science Workshop on September 23–24, 2026, at the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/companies/219">C³AL Laboratory</a> at Cal State LA. Registration is free, and meals and refreshments will be provided throughout the workshop.&nbsp;<h4>Registration</h4><blockquote>👉<a target="_blank" rel="noopener noreferrer" href="https://forms.cloud.microsoft/pages/responsepage.aspx?id=iYeNbqIuykW7qZP4_jUEVbznDB40eK1PgjPzhHyb__9URTFTTFA5UEEzQ1A4MUtFV0o4TEJTNlZCOS4u&amp;route=shorturl">Register HERE</a>Space is limited, register today!<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_LECO_Separation_Science_Workshop_registration_332543a18e.jpg" alt="LECO: LECO Separation Science Workshop - QR code for registration" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_LECO_Separation_Science_Workshop_registration_332543a18e.jpg 156w," sizes="100vw" width="437" height="437"></blockquote><h4>Hand-on Experience with the LECO Complex Chemical Composition Analysis Lab C3AL</h4><ul><li>Work directly with LECO instruments in the C3AL Laboratory</li><li>Learn complete analytical workflows from sample to answer</li><li>Get expert guidance from LECO application scientists</li><li>Develop methods and solve real-world challenges</li><li>Collaborate, ask questions, and build your skills</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Cal_State_LA_The_LECO_Pegasus_BTX_system_in_Cal_State_LA_s_LECO_Complex_Chemical_Compositional_Analysis_Lab_enhances_research_and_student_training_in_advanced_chemical_analysis_cover_b739e727ca.jpg" alt="Cal State LA: The LECO Pegasus BTX system in Cal State LA’s LECO Complex Chemical Compositional Analysis Lab enhances research and student training in advanced chemical analysis" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Cal_State_LA_The_LECO_Pegasus_BTX_system_in_Cal_State_LA_s_LECO_Complex_Chemical_Compositional_Analysis_Lab_enhances_research_and_student_training_in_advanced_chemical_analysis_cover_b739e727ca.jpg 227w," sizes="100vw" width="1252" height="863">The first day will focus on the fundamentals and theory of comprehensive two-dimensional gas chromatography (GC×GC), with an emphasis on understanding how GC×GC can enhance your research, solve complex analytical challenges, and support your laboratory or company goals.&nbsp;The second day will be dedicated to hands-on activities, giving participants the opportunity to work directly with LECO instrumentation, learn practical analytical workflows, and analyze their own samples with guidance from LECO application scientists.&nbsp;Whether you are new to GC×GC or looking to expand its use in your research or organization, this workshop offers a unique opportunity to learn, explore, and apply the technology in a practical setting. Space is limited, so register early!<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Cal_State_LA_LECO_QUADJET_G_Cx_GC_coupled_to_Pegasus_BT_4_D_TOM_MS_in_the_Complex_Chemical_Composition_Analysis_Lab_C_AL_077a14ae34/Cal-State-LA-LECO-QUADJET-GCxGC-coupled-to-Pegasus-BT-4D-TOM-MS-in-the-Complex-Chemical-Composition-Analysis-Lab-(CAL).jpg" alt="Cal State LA: LECO QUADJET GCxGC coupled to Pegasus BT 4D TOM MS in the Complex Chemical Composition Analysis Lab (C³AL)" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Cal_State_LA_LECO_QUADJET_G_Cx_GC_coupled_to_Pegasus_BT_4_D_TOM_MS_in_the_Complex_Chemical_Composition_Analysis_Lab_C_AL_077a14ae34/thumbnail_Cal-State-LA-LECO-QUADJET-GCxGC-coupled-to-Pegasus-BT-4D-TOM-MS-in-the-Complex-Chemical-Composition-Analysis-Lab-(CAL).jpg 234w," sizes="100vw" width="1949" height="1299">

LECO Separation Science Workshop

An international research team, which included scientists from the Faculty of Science at Palacký University and the Institute of Physics of the Czech Academy of Sciences, has succeeded in unraveling the complex mechanism by which a chemical bond is formed during a collision between molecules. The experts found that the reaction only takes place if the molecules are oriented towards each other within a very narrow range of angles – within the so-called cone of reaction. This joint research has thus provided an answer to one of the fundamental questions of chemistry: under what conditions do chemical bonds form between molecules. The results of the study&nbsp;Spatially resolving the cone of reaction for a single molecule&nbsp;were published in the prestigious scientific journal&nbsp;Science.Many chemical reactions begin with the collision of two particles. However, for a new chemical bond to form, it is not enough for the molecules simply to come into contact. Their collision must occur with sufficient energy, in the correct relative orientation and at the right location. Under normal conditions, such as in solutions or gases, molecules collide chaotically, and the precise parameters of these collisions cannot therefore be controlled.<h4>Molecules under control</h4>Scientists were able to control the collisions of individual molecules on a copper surface and monitored the process using a scanning tunnelling microscope. They used the instrument not only to visualise individual molecules, but also to deliberately accelerate the reactants towards one another. They subsequently analysed each collision with atomic-level resolution. This enabled them to determine unequivocally whether a new chemical bond had formed between the molecules.<h5>“What is hidden in the statistics of billions of collisions in conventional chemistry, we have managed to break down into individual cases and map directly.” Adam Matěj</h5>A key finding of the study is that the outcome of a collision is determined by the extremely precise orientation of the molecules. A new bond was formed only when the target molecule was oriented within a few degrees of the direction of movement of the other molecule. When rotated by more than fifteen degrees, the molecules simply bounced off each other without any reaction.<h4>The precise orientation of the molecules is crucial</h4>“For the first time, we were able to observe, using a single molecule, exactly how precisely it must be oriented for the reaction to take place at all. What is hidden in the statistics of billions of collisions in conventional chemistry, we have managed to break down into individual cases and map directly,” said Adam Matěj from the Department of Physical Chemistry at the Faculty of Science.The theoretical part of the study, in which researchers from Palacký University and the Institute of Physics of the Czech Academy of Sciences were involved, played a significant role. Using quantum-mechanical calculations, they explained why the ‘reaction cone’ is so narrow. It turned out that the reactive carbon atom is surrounded by hydrogen atoms, which block the access of the reacting molecule from almost all directions.<h4>The arrangement of atoms restricts access to the reaction</h4>The calculations also shed light on a surprising experimental result. The chemical reaction took place even when the molecule moved along an adjacent row of copper atoms, where, according to the original assumptions, no bond should have formed.<h5>“The strength of this work lies in the fact that the experiment and theory have been brought together into a single picture. The microscope showed what happens during the collision, and the calculations explained why.” Pavel Jelínek</h5>“The explanation lies in the slight displacement of a single copper atom on the surface. The target’s bond to the surface pulls it out of its position and brings it close enough to the neighbouring row that it can literally take over the projectile and direct it to the correct spot. This shows that the surface is not merely a passive substrate, but actively participates in the reaction itself and can even facilitate pathways that would otherwise be unfavourable,” noted Adam Matěj.<h4>The surface also determines the course of the reaction</h4>The results are significant for the development of so-called surface reactions, in which new materials and nanostructures are purposefully assembled from individual molecules. A better understanding of the influence of the spatial arrangement of molecules will enable the design of molecular building blocks so that they bond more reliably and efficiently. This represents an important step towards the development of technologies based on the controlled construction of structures atom by atom.“The strength of this work lies in the fact that experiment and theory have been brought together into a single picture. The microscope showed what happens during the collision, and the calculations explained why. Without a theoretical model, we would have found it difficult to discover that the movement of a single surface atom is behind the unexpected course of the reaction,” added Pavel Jelínek from the Institute of Physics of the Czech Academy of Sciences.<blockquote>The study&nbsp;Spatially resolving the cone of reaction for a single molecule&nbsp;was produced in collaboration between researchers from the University of Graz, the Institute of Physics of the Czech Academy of Sciences, Palacký University in Olomouc, Charles University and Humboldt University in Berlin.</blockquote>

Scientists reveal when chemical bonds form in molecular collisions 

Injecting water into a gas chromatography (GC) system has always raised concerns for analysts. Many wonder if water will damage their <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products?category=7&amp;manufacturerItems=50">GC column</a> or instrument. In fact, one of the most common questions in gas chromatography water analysis is whether aqueous samples can be safely introduced without compromising results.Selecting the right GC column for water analysis and following proper injection techniques can minimize the risk of column damage and maintain reliable analytical results.<h3>Why Water Injections Are Risky in GC</h3>Water injections in gas chromatography columns are risky due to the following reasons:<h4>Backflash Issues</h4>Water expands significantly when vaporized at high inlet temperatures (e.g., 250–300 °C). If the expansion volume exceeds the inlet liner capacity, backflash can occur. This contaminates injector parts, leaving residues that cause ghost peaks, carryover, sample loss, and elevated baselines, ultimately reducing reproducibility and accuracy.<h4>Stationary Phase Degradation</h4>As a highly polar solvent, water can hydrogen bond with stationary phase polymers such as polyethylene glycol (PEG) or wax phases. Repeated exposure alters selectivity, shifts retention times, and may increase bleed in non-crosslinked phases. While older immobilized PEG phases are especially vulnerable, modern chemically bonded and crosslinked stationary phases offer improved resistance, making them more suitable to inject up to 100% water samples.<h4>Incomplete Vaporization</h4>Water’s high boiling point and poor wetting of non-polar stationary phases can result in incomplete vaporization. This may lead to peak splitting, band broadening, or reduced sensitivity. For this reason, injection settings need to be finely adjusted to avoid these effects.<h4>Detector Issue</h4>Standard GC detectors do not directly detect water. Excess water injected into a flame ionization detector (FID) can quench or even extinguish the flame, while moisture in an electron capture detector (ECD) can interfere with electron capture efficiency, suppressing signals or causing false responses.<h3>Choosing the Right GC Columns for Water-Containing Samples</h3>Here are some strategies that can help you increase the life of GC columns when analyzing water-containing samples.<ul><li>Use of cross-linked phases: Modern stationary phase design has greatly improved tolerance to water injections in GC. Cross-linking chemically bonds the stationary phase to the silica surface, making it far more resistant to leaching or washout from polar solvents. Traditionally immobilized but not cross-linked phases were much more vulnerable to degradation. For example, polyethylene glycol (PEG) phases are inherently hydrophilic and prone to water damage unless cross-linked. With technologies such as engineered self-crosslinking (ESC), used in Phenomenex <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/1571">Zebron ZB-WAXplus GC columns</a>, PEG phases can withstand repeated water injections without significant loss of efficiency.</li><li>Use of non-polar columns: Non-polar bonded and cross-linked columns (e.g., PDMS phases) are inherently resistant to water damage, though incomplete vaporization may still affect peak quality.</li></ul><h3>Tips to Protect Your GC System from Water Damage</h3>Implementing a few key tips can help protect your GC system from water damage. Here are some of the important recommendations:<ul><li>Keep injections small: Limit water injections to ≤0.2 µL to minimize backflash and protect the stationary phase.</li><li>Select the right liner: Use an appropriately sized inlet liner (e.g., 4.0 mm ID tapered or with a double gooseneck) to reduce backflash. A deactivated glass wool plug can promote rapid vaporization, though it may not be suitable for all analytes.</li><li>Reduce syringe carryover: Rinse syringes with a 50:50 methanol–water mixture between injections. In some methods, preparing samples with a small percentage of methanol can improve reproducibility and syringe performance.</li><li>Optimize solvent and injector conditions: Limit water injections to ≤0.2 µL to minimize backflash and protect the stationary phase.</li><li>Adjust carrier gas conditions: Ensure your <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/article/5538">gas chromatography injector setup</a> is correct to prevent water buildup. Combining water with a lower-expansion solvent (e.g., methanol) and maintaining an optimized injector temperature helps improve vaporization while limiting expansion.</li><li>Maintain a clean carrier gas supply: Replace gas cylinders before they are nearly empty to avoid backflow or moisture intrusion into the system While injecting water into a GC system is not simple and ideal, it can be managed safely with the right precautions. By choosing the appropriate stationary phase, following proper GC injector setup, and maintaining your instrument, you can conduct gas chromatography water analysis with confidence. For more information on GC hardware and maintenance, explore the <a target="_blank" rel="noopener noreferrer" href="https://www.phenomenex.com/resources/knowledge-center/gc-knowledge-center/understanding-the-essential-components-of-gas-chromatography">key parts of a GC instrument</a>.</li></ul>

Water Injections in GC: Is it Safe?

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Phenomenex is a global technology leader committed to developing novel analytical chemistry solutions that solve the separation and purification challenges of researchers in industrial, government and academic laboratories.

Phenomenex

In 1936, the Laboratory Equipment Company introduced the first rapid carbon determinator for the American iron and steel industry.  Today, almost 80 years later, LECO is recognized globally as a leader in the development of high-quality analytical instrumentation, mass spectrometers, comprehensive two-dimensional chromatography, metallography & optical equipment as well as consumables.

LECO

Palacký University Olomouc (UP) is an internationally respected and scientifically and academically highly productive university in Central Europe. Founded 22 December 1573, it is the second-oldest university in the Czech Republic and the oldest one in Moravia. For 450 years it has contributed to the intellectual wealth of society and to its scientific, cultural, and social development.

Palacký University Olomouc

New Food magazine

SepSolve Analytical

This e-seminar focuses on the application of nominal and high resolution time-of-flight mass spectrometry coupled to gas chromatography and thermal inlet systems for the comprehensive quantitative and/or qualitative analysis of petroleum derived matrices, from middle distillates to vacuum residues.
<h3>Highlights include:</h3>
<ul>
<li>Adoption of GCxGC towards high temperature and phase considerations</li>
<li>Determination of boiling point distribution by high temp GCxGC</li>
<li>Classification according to compound class</li>
<li>Derivation of absolute quantitative information</li>
</ul>
<blockquote>
Presenter: Thomas Groeger (Joint Mass Spectrometry Centre, Univ of Rostock and Helmholtz Zentrum Muenchen)
</blockquote>

Pixabay/SatyaPrem: High Temp GCxGC of Light Crude Oil and High Boilers

High Temp GCxGC of Light Crude Oil and High Boilers

Flow modulation simplifies the way you perform GCxGC as it provides a number of advantages over thermal modulation, including easy setup and no use of cryogens. In this e-seminar, you’ll hear from John Seeley, a preeminent researcher in flow-based modulation techniques. He discusses the underlying principles of flow-based GCxGC theory, demonstrates its use with applications, and provides an in-depth analysis of when GCxGC flow modulation is an effective approach, and when it may not be the best option. This overview is meant to provide an educational backdrop for those who are interested in further understanding GCxGC and how it can play a role in their lab.
<h3>LECO&#39;s New FLUX™ GCxGC Flow ModulatorPegasus_BT4D_FLUX_Operator</h3>
Our innovative FLUX GCxGC flow modulator was designed with one goal in mind—to make GCxGC more routine, accessible, and easy to use in your lab. The flow modulator&#39;s concept is based on the sound and easily understood principles first articulated by Seeley et al. on diverting flow, (visit the webinar above if you want to learn more). This extraordinarily simple design comprising of a cross shape and a sideways T, is not only easy to setup and get started, but its ease-of-use makes it the most cost-effective option for GCxGC analysis.
<h3>Advantages</h3>
This flow-based modulator is perfect for those who want to perform robust GCxGC analysis, but who don&#39;t need the sensitivity of standard quad jet thermal modulation. Ideal samples should be complex, but relatively concentrated. Appropriate applications include petroleum and fragrance analyses such as the classic weathered crude oil example pictured below, which shows a GCxGC plot generated on our Pegasus® BT platform using the FLUX flow modulator.
<blockquote>
Presenter: John V. Seeley (Oakland University, Department of Chemistry)
</blockquote>

GCxGC with Flow Modulation: A Simple Approach to Resolving Complex Mixtures

This webinar will provide an overview on the topic of analyzing various fat species in foods and methods to determine various classes from total fat to various lipid fractions and the wide variety of analyses available for fat determination. Topics discussed will include the analyses of fatty acid methyl esters (FAMES) in foods and the use of comprehensive two-dimensional gas chromatography (GC x GC) for the enhanced separation of highly complex mixtures. Advances in GC column stationary phases and new phases based on ionic liquid technology for the analyses of saturated and polyunsaturated FAMES will be discussed aswell as the use of GC×GC in the field of food lipid analysis. The considerable advantages of the two-dimensional approach (both with and without MS detection), in experiments related to a series of lipid volatiles (fatty acids, sterols, oxidation products, fatty alcohols, etc) will be illustrated.
<h3>Featured in this webinar:</h3>
<ul>
<li>Overview the wide variety of methods available for the analysis of fat in foods.</li>
<li>Examine traditional and new classes of GC Stationary Phases for the evaluation of various FAME species.</li>
<li>Discuss the power of two-dimensional gas chromatography (GCxGC) for separating highly complex mixtures and how it can be combined with mass spectrometry for analyzing volatile and semi-volatile analytes</li>
</ul>
<blockquote>
Presenter: Len Sidisky (R&amp;D Manager, Gas Separations Business Unit, Sigma-Aldrich)
</blockquote>
<blockquote>
Len discusses traditional and new stationary phases for FAME analyses and how these can be used to resolve various fatty acid species.
</blockquote>
<blockquote>
Len holds a Masters of Food Science from Penn State University and is the author of numerous papers, seminars, and other presentations on capillary gas chromatographic and SPME theory, techniques and applications. He has lectured worldwide, including the United States, Europe, Japan, China and in South America on various chromatographic techniques primarily focusing on capillary GC, SPME and air monitoring devices/ adsorbents.
</blockquote>
<blockquote>
Presenter: Dr. Peter Q. Tranchida (Associate Professor, Food Chemistry in the Department of Pharmaceutical and Health Product Sciences, University of Messina)
</blockquote>
<blockquote>
Dr. Tranchida discusses the use of GC×GC in the field of food lipid analysis. The considerable advantages of the two-dimensional approach (both with and without MS detection), in experiments related to a series of lipid volatiles (fatty acids, sterols, oxidation products, fatty alcohols, etc) will be illustrated and discussed. 
</blockquote>
<blockquote>
Dr. Tranchida focuses on the study of complex food samples using advanced chromatography processes, such as fast and very-fast GC systems. An emphasis of his work is the evaluation of ultimate generation stationary phases (i.e., ionic liquids), and the development and application of classical multidimensional and comprehensive chromatography systems. In the field of GC×GC, he has performed applications, method optimization studies, and introduced a new form of flow modulation. At the”9th GC×GC symposium” he was awarded the “John Phillips Award” for outstanding achievements in the field of comprehensive two-dimensional gas chromatography. He has co-authored 100 scientific papers, 16 book chapters, and 240 oral/poster presentations.
</blockquote>

Pixabay/engin akyurt: Novel Techniques and New Advances in the Analyses of Fat species in Foods

Novel Techniques and New Advances in the Analyses of Fat species in Foods

<h3>In this webinar you will:</h3>
<ul>
<li>Learn the basics of GC×GC and what it offers for analysis of TPH-CWG</li>
<li>See how offline sample fractionation can be eliminated, speeding up analysis time and reducing costs </li>
<li>Hear about the productivity advantages of dual-channel GC×GC-FID </li>
<li>See ChromSpace software in action for fast and simple control and data processing</li>
</ul>

Pixabay/Dennis Larsen: Dual-channel GC×GC-FID for routine analysis of total petroleum hydrocarbons (TPH-CWG)

Dual-channel GC×GC-FID for routine analysis of total petroleum hydrocarbons (TPH-CWG)

Cannabis is one of the world’s most frequently used drugs of abuse and with recent legislative changes in Canada and multiple states of the USA, the need for robust testing of cannabis products is on the rise. However, this can be a challenging prospect due to the sample and matrix complexity.
<h3>In this webinar you will:</h3>
<ul>
<li>Learn the basics of GC×GC and what it offers over and above standard GC</li>
<li>Hear about the advantages of GC×GC-FID for robust and simple profiling of cannabis terpenes </li>
<li>See the additional benefits that mass spectrometry can bring for differentiating cannabis strains</li>
</ul>

Pixabay/John Miller: GC×GC for improved data quality in profiling cannabis terpenes

GCMS webinars focusing on GCxGC - page 11