Restek Inspires Future Scientists at STEM Fair

Teaching the concepts of chromatography to elementary and middle school students in Central Pennsylvania is another way Restek connects with and gives back to the community.

An auditorium full of middle schoolers may seem like a tough audience for teaching new scientific concepts, but in Restek’s experience, they are quite attentive and engaged. So, employees at Restek love taking the opportunity to share their knowledge with area youth.

“I could go through a slide show presentation, but something tells me you wouldn’t be that interested in it. So, I’m going to get you involved and teach you through action,” Scott Grossman, a content development specialist at Restek, told an auditorium of more than 200 students in April.

For years, teams at Restek have presented a variety of interactive performances to elementary and middle school students about chromatography. This past April, Grossman, with his colleagues Samantha Harter, Fang-Yun Lo, and Titus Morehead, visited Park Forest Middle School to present during the school’s STEM Fair. The annual event encourages student involvement and future careers in science, technology, engineering, and math (STEM).

“We keep inviting Restek back because their presentation is high quality and they do a good job at communicating what they do at an appropriate level for the students,” Mike Bierly, an eighth-grade science teacher at Park Forest, said.

This year’s presentation teaches chromatography by comparing it to a party. The presenters invite dozens of students on stage to create a party atmosphere that will function like a chromatography column’s stationary phase. Then, other students pass through the party—some having been instructed offstage to interact extensively with other partygoers, while others were instructed to interact very little and “elute” quickly, ignoring the party and passing straight to the food table. As students reach the food table, “peaks” in an illustrative chromatogram are generated. Grossman explains that analyzing these different types of partygoers is very similar to how chemists use chromatography to analyze the contents of liquid and gas samples—compounds interact with the column’s stationary phase to different degrees, allowing them to be separated and, ultimately, identified.

“It’s fun to see the students engage and start to understand the concepts,” said Harter, a process engineer at Restek.

Lori Dundon, a Restek marketing communications manager, kick-started Restek’s engagement with local elementary and middle schools in Central Pennsylvania years ago when her kids were attending Park Forest Middle School.

“I wanted my kids to understand what I do for work,” she said.

Grossman took on the challenge of developing a presentation and has since offered it, and others, to many local schools and thousands of future scientists.

“It’s like I always tell the students—it doesn’t matter what you end up doing in your career, you need to be a good communicator,” he said.

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Restek at ISCC & GCxGC 2017

Going to ISCC & GCxGC in Fort Worth this year? Don’t miss these presentations by Restek’s expert chromatographers. Stop by our booth or attend a presentation—we’re excited to share our research and discuss solutions to your toughest chromatography challenges!



GC-MS Analysis of Phthalates: Comparison of GC Stationary Phase Performance

Dan Li, Rebecca Stevens, Chris English, Anzi Wang

Phthalates are ubiquitous in the environment and have attracted attention due to their potential adverse impact on human health. For this reason, detection and separation of phthalates has become a necessity. Gas chromatography is an effective approach for separating phthalates, and it can be paired with several detection techniques, including electron capture (ECD), flame ionization (FID), and mass spectrometry (MS). In this study, Pro EZGC gas chromatographic modeling software was employed to determine the optimal stationary phases and conditions for phthalate GC-MS analysis. The separation of phthalates was compared on seven different stationary phases: Rtx-440, Rxi-XLB, Rxi-5ms, Rtx-50, Rxi-35Sil MS, Rtx-CLPesticides, and Rtx-CLPesticides2 phases. In all cases, 18 EPA- and EU-listed phthalates were analyzed in less than 6 minutes. In addition, an extended list of 37 phthalates was analyzed in less than 40 minutes using an optimized method. Both Rtx-440, which is unique to Restek, and Rxi-XLB columns showed the best resolution of the complex phthalate mixture.


Evaluating Mass Overload on Superficially Porous Particles

Edward G. Franklin, C. Vernon Bartlett, Justin Steimling, Ty Kahler

Superficially porous particles (SPP) are a powerful analytical tool for achieving fast LC analyses.  The solid, impermeable core present in these particles increases the column efficiency by decreasing the diffusion path. However, the solid core also significantly reduces the surface area that is typically available in traditional fully porous materials (FPP). There is a potential concern that arises from a reduction in surface area: column loading ability. Column overloading (mass overload) occurs when the amount of material injected onto the column exceeds the available active sites of the stationary phase. The purpose of this study was to evaluate a series of analytes and determine the effects the solid core has on the loading ability of superficially porous particles.


Affecting Selectivity and HILIC Retention on a FluoroPhenyl Stationary Phase

Vernon Bartlett, Edward G. Franklin, Frances Carroll, Shun-Hsin Liang, Sharon Lupo, Ty Kahler

In this study, we have set out to explore the retention mechanisms of the FluoroPhenyl stationary phase. The FluoroPhenyl phase may be described as having mixed-mode and/or HILIC retention and selectivity. HILIC and mixed-mode capabilities offer retention mechanisms that vary, or are orthogonal to, typical reversed-phase columns like C18s. These chemical interactions are generally not well understood or easily demonstrated, which may be frustrating and leave chromatographers not using the phase to the fullest potential.

The FluoroPhenyl phase offers unique selectivity by incorporating strongly electronegative fluorine atoms on a phenyl ring. In addition to traditional reversed-phase dispersive interactions, this phase exhibits polar, cation-exchange, and HILIC retention mechanisms. Our focus in this presentation is on method changes, including temperature, mobile phase composition, acid strength and concentration, and how these changes affect the selectivity of targeted analytes. By demonstrating the influence of method changes on this phase, we aim to gather a better understanding of the interactions provided by the FluoroPhenyl phase and its use as a HILIC or mixed-mode phase.

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