Author Archive

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 […]

A Few Ideas for Chromatographers During the Covid-19 Situation

The other day, I and some of my colleagues started a discussion about how chromatographers are handling the current Covid-19 situation. Some are working from home, and some are experiencing temporary closures. Those that are working are likely working under “new” conditions – social distancing, additional personal protective equipment, possibly working different shifts, etc. Since […]

How (Not) To Cut Your Capillary Column

There are numerous ways to cut a capillary column. Restek has several tools to accomplish this job. There are sapphire scribes, ceramic scoring wafers, wafers with a handle, and diamond blade column cutters. There are also some tools manufactured by other companies that will cut a capillary column. The choice is typically personal preference. No […]

Utilizing Restek Reference Standards for Residual Solvent Testing

Restek manufactures several different residual solvent standards.  These can be used for testing according to USP <467>, the EP monograph, or other residual solvent assays, such as medical cannabis testing.   The calculations involved for the use of these standards has led to questions for our technical team.  This post should help provide guidance for their […]

Choosing an Internal Standard

Adding an internal standard (IS) to an assay can be an excellent way to often improve method precision and accuracy. An IS can account for signal suppression (or enhancement), that may be caused by the sample matrix. When using an IS, the response of your target compound(s) is compared to the response of the IS. […]

Can I use a non-MS column in my mass spectrometer?

Previously, I wrote about using a MS column for non-mass spec applications.  There are occasions when you come across a method or journal article where a non-MS column is used in a mass spectrometer.  People ponder if this is a good idea, and often contact Tech Support for guidance.  So, can I use a non-MS […]

Can I use an MS column for non-mass spec applications?

Some of you may have read my response in a past Restek Advantage, where I was questioned about the “MS” designation on some Restek GC columns.  I explained how the MS suffix is for a mass spec grade column.  These MS designated columns are tested and guaranteed for low bleed performance, which is ideal for sensitive detectors like […]

Restek has 4-Methylcyclohexane methanol (MCHM) Standards

Restek has MCHM standards available!  Currently, it is a custom standard at a concentration of 1000 µg/mL prepared in P&T Methanol (Catalog #568935).  If you require a solution at a different concentration or in a different solvent, you will need to obtain a quote for the product.   Currently, our Innovations team is working with […]

How can I test for 4-Methylcyclohexane methanol?

On January 9th, approximately 5000 gallons of 4-Methylcyclohexane methanol (MCHM) seeped from a storage tank into the Elk River in southern West Virginia.  Eventually, the MCHM  (CAS #34885-03-5) made its way into the water supply prompting Governor Tomblin and President Obama to issue a state of emergency for the affected counties.  The story can be […]

Why are Restek capillary columns tested with different components? What can I, as a user, do with this information?

We have all bought a new capillary GC column, but only a few of us have probably reviewed the QC test report. For those of you who may have reviewed a report, you might have wondered about the data presented. In this post, I hope to clarify some of the information in regards to the […]