Archive for the ‘LC’ Category

Top 16 for 2016 – Restek LC Article Makes the Cut

If you are an avid chromatographer you likely subscribe to LC/GC magazine or its popular electronic version, E-Separation Solutions. It is definitely the place to go for news and information related to all things Chromatography. Over the years Restek has had many an article published in LC/GC and, full disclosure, we advertise there as well. Who […]

Fluorophenyl LC Phases- what you should know

They may be called PFP, PFPP, pentafluorophenyl, fluorophenyl or F5 phases. What they all have in common is the structure shown above (the pentafluorophenyl  group) attached to the silica particles. Most modern phases contain a propyl spacer between the above group and the silica, so that the phase looks something like this:     A […]

Need parts for your Agilent 1100? HP 1050? Restek has you covered.

As of May 31, 2015, 1100 Series HPLC systems were categorized “End of Guaranteed Support” (EGS) by Agilent. Agilent would prefer it if you purchased a new system from them, but 1100 HPLCs are dependable workhorses. Why not keep them running with instrument replacement parts from Restek? Check out our selection, easily sorted by instrument and module: […]

Can HPLC-UV Be Used For Terpenes Analysis In Cannabis?

While HPLC may be tempting to use for terpenes analysis, a GC/FID or GC/MS is really the most straightforward and recommended way of analyzing terpenes in cannabis. Terpenes, being relatively volatile and neutral, lend themselves rather nicely to GC in general. As you can see from Figure 1 below, coelutions of the cannabinoids and terpenes are very likely when […]

Update on Guard Cartridges for Trident Holders

        You may have seen my last blog post about guard holders and cartridges that we have available for our various LC product lines, “Which guard cartridges and holders go with which LC analytical columns?” Along those lines of discussion, the following note is available to also show what specific products are […]

Why Biphenyl is a very interesting primary choice as stationary phase in LC..

Being a GC chemist for almost 38 years I always wondered why most LC separations are performed on a C18. A C18 is an extremely good non-polar stationary phase and is the foundation of reversed-phase chromatography, where polar mobiles phases are used with non-polar stationary phases. But there are so many C18 phases, how do […]

Which guard cartridges and holders go with which LC analytical columns?

As our family of LC products has grown, so have our choices for columns and accompanying guard cartridges. Here is a handy chart to show which guard holder and guard cartridges were intended for use with each type of analytical column. Please feel free to click the links to access each group of products on […]

What can I use to filter my mobile phase?

If you are using mobile phase that contains salts or, generally, any components that are weighed out for its preparation, you will need to filter the solution before using with HPLC or UHPLC. The most common type of filtration is membrane microfiltration. We sell an extensive group of products for this and they are discussed […]

What can I use as a cap for my mobile phase bottles?

Our choices for mobile phase bottle tops are based primarily on two different products. The first product is the Hub-Cap Bottle Top, catalog #26541. This is designed to fit a 4-Liter solvent bottle. :     The body (also called insert) of the Hub-Cap Top is cap is made of inert PTFE and has three […]

What is the pressure limit for my LC column?

This is a question we get in Tech Services fairly often.  Unfortunately, we are not able to provide a published limit for every column that we produce, but here are a few of them that we have specified: For 3 and 5 um fully porous particle ROC LC columns, the maximum operating pressure is 400 […]