Archive for the ‘Miscellaneous’ Category

Chemical Reference Standards: Don’t Just Snap and Pour (Part 2)

Several years ago, my colleague, Alan Sensue wrote Chemical Reference Standards; don’t just snap and pour. In it, he described a personal experience where he mixed several expensive reference standards together assuming the vials contained exactly 1 mL. It was a mistake he has remembered for some time. Here are a few other examples as […]

Column and reference standards documentation – one click away

Did you know that many forms of documentation, such as column and standard CofAs, are available one click away  from our homepage? From here, pdfs of safety data sheets (SDSs), certificates of analysis (CofAs) for LC columns and GC guard columns, CofAs and datapacks for reference standards, and more, can be accessed. Our website contains […]

Troubleshooting 101

Like most folks who work in the lab, you likely have had some downtime in the lab due to various reasons, like a column, instrument, sample prep, standards, and even application or method conditions. Troubleshooting then commences. Details are often needed, in order to get the bigger picture. One of the most important troubleshooting tools […]

Want to know how to properly choose a column – please step inside

Often times in technical service there will be a request for a column that can provide a certain separation on a lone pair of analytes.  Take for example, the separation of CO from CH4 from one another. This separation is very easily done on any porous polymer column. What is sometimes not taken into account […]

Solid Phase Extraction: Separation is the Foundation of this Preparation!

In a previous post, we made the case that the foundation for analytical separations is sample preparation.  In this post, we would like to talk about how it works the other way around, too!  Separation can actually be the foundation for sample preparation.   In particular, we would like to talk about how solid phase extraction […]

Preserve your SRM transition windows by replacing the same amount of column you remove during maintenance

I’ve been working on a detailed PCB congener analysis using the TSQ-9000 with the AEI. Typically this analysis is done by EPA Method 1668C, which uses high resolution MS. We get some specificity from the selected reaction monitoring, but there are some shortcomings when compared to high resolution data. Where the TSQ-9000 really shines is […]

The Foundation of Separation is Preparation

Restek is known as a leader in the field of chromatographic column technology.  The idea is built into our very identity – resolution technology is at the heart of Restek.  We also believe that proper sample preparation sets chromatography up for success, though, by reducing the incidence of confounding results and prolonging the lifetime of […]

Water, can’t live without it so how can we deal with it (and adsorbent columns)

Often the gas samples contain some water vapor. Although we are usually not interested in the amount of moisture present in the sample, if we don’t dry it, the water will be injected onto the column with our sample. Alan, in his blog, has previously discussed the effects of water on capillary columns with liquid […]

Thermo Trace 1310 Inlet Temperature Profile vs Agilent 7890 for Split/Splitless Injectors

Several years ago, my colleague Scott Grossman wrote an excellent article entitled “It’s a Matter of Degrees, but Do Degrees Really Matter?”  He measured the temperature profile across various Agilent inlets, demonstrating different gradients in temperature exist across inlets, depending on the type of inlet and even among the same inlet type.  One consistent finding […]

Spring Cleaning Your GC System

Spring has sprung and now is a good time to give your GC system a thorough going over.  There is routine maintenance that we should perform all the time to keep the GC in tip-top condition like changing the liner, o-ring, septum, using your electronic leak detector and column trimming; but there is also periodic […]