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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LECO Separation Science Workshop

Water Injections in GC: Is it Safe?

Scientists reveal when chemical bonds form in molecular collisions