Archive for 2016

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 […]

Some notes about Fats and Oils in Food and about FAME and FAMEWAX

In Europe, the last transition periods named in REGULATION (EU) No 1169/2011 on the provision of food information to consumers are running out on Dec. 13th, 2016. Since then, a nutrition declaration is mandatory for nearly all packed food in Europe, wherein the amounts of fat, saturates, carbohydrate, sugars, protein and salt have to be included. […]

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 […]

Two Detector Solution to Analyzing Sulfur

Dan Li, Katarina Oden, Chris English, and Jason Herrington Sulfur compounds are reactive, corrosive to pipes, and destructive to catalysts in petroleum refineries. Sulfur emission are strictly regulated globally. When released into the atmosphere sulfur dioxide converts to sulfuric acid resulting in adverse effects on human health and the environment. Sulfur detection is found useful […]

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 […]

Leak Detector Lithium Ion Battery

Lithium ion batteries have been in the news quite a lot recently, and not all of it has been positive.  There have been numerous incidents of different products from airplanes to hoverboards to mobile phones catching fire during charging or operation.  These problems occur when there has been damage to the cells’ structure or to the […]

Material Composition of Resprep® Manifold Replacement Parts

A customer asked me yesterday what material certain items for our SPE manifolds were made from.  The answers are below.     Catalog # 26083 is Nylon Catalog #’s 26130 & 26131 are Polypropylene Catalog # 26084 is PTFE   For those of you who need to avoid sample contact with PTFE, we also sell […]

“Absolute” Pressure (psia) vs “Gauge” Pressure (psig)

Here is the scenario: You have just received your brand new Ashcroft Test Gauge. Why??? Because you know that the gauge on your canister is not accurate enough for making reliable quantitative dilutions. You notice that your brand-spanking-new Ashcroft Test Gauge is not reading zero, like so: Now you are starting to FREEAAK OUT!!! Because […]

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 […]