Posts Tagged ‘Raptor’

How can I use Raptor columns and the EXP Direct connect holder with stainless steel fittings?

Some customers may find themselves with this scenario. You have an HPLC instrument with existing stainless steel tubing and fittings and you are getting ready to install a Raptor column. The end of your tubing may very well look like the one shown above. Here are some questions you might have.   Can I attach […]

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 […]

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 […]

Here’s to HILIC: tailor-made for the MS analysis of polar analytes and highly water-soluble species

There is much discussion these days about Hydrophilic Interaction Chromatography (HILIC) and the options it provides today’s analysts. And there should be.  It’s powerful for analysts working with polar metabolites or highly water-soluble compounds, namely when using MS/MS techniques. Since phase chemistry is Restek’s specialty, and we have designed our Raptor SPP LC column line for […]

Technical Service “Red Flags” – LC

This post is an extension of a series of posts pertaining to “Red Flags” my colleague has written, pertaining to GC analysis. These are situations and symptoms that tell us in the Tech Service group that something is just not right. So what are examples of some “Red Flags” that we commonly see for HPLC?  […]

Analysis of Nicotine and Related Compounds in Urine Using Raptor™ Biphenyl

As Applications Chemists in the LC lab, one of the most exciting parts of our jobs is the variety of analyses we are exposed to. One day you are developing a method for potency analysis in cannabis samples, the next you are looking at anti-epileptic drugs in urine.    We’re regularly challenged to think outside the […]

All of my peaks are tailing… What should I do?

I get quite a few customer questions concerning peak tailing during LC analysis, and how to best troubleshoot this issue.   Peak tailing may be attributed to a variety of different causes including secondary interactions, contamination, column loading, etc.   This list goes on and on.   I usually ask a few key questions, and generally can give […]

Raptor Biphenyl LC Columns provide the data needed for global antibiotic testing

Because the widespread use of preventative veterinary antibiotics has resulted in increased antimicrobial resistance in humans, the US Food and Drug Administration (FDA) released guidelines to address the issue in food animals (December 11, 2013). Similar constraints are also prevalent in the European Union.  Recently, European Researchers1 developed a validated method for the determination of […]

Shifting Analyte Retention Times or Matrix Interferences?

Occasionally, we will get a Technical Service call about peak retention times moving during a customer analysis.  Early eluting compounds are especially prone to this shifting, but the issue can often be attributed to matrix interferences that are also not well retained.    Pregabalin and Gabapentin are two antiepileptic drugs typically analyzed by LC-MS/MS.  Because of […]

Mass Overload on Superficially Porous Particles

The benefits of superficially porous particles are without question.  Who wouldn’t want to perform faster separations without the need for expensive UHPLC instrumentation?  It sounds too good to be true.  There must be some drawback – right? The solid, impermeable core present in Raptor™ particles increases column efficiency by decreasing the diffusion path at the […]