Chromatography Forum

Primesep mixed mode columns. I've been working with these columns for 2 months and have developed separations on these mixed mode columns which are impossible on anything else available. This has been a dream column for years. Separating polar molecules, ionic molecules and neutrals in one method. Most of the time isocratic too! No one else has this technology that I know of. I'm certain all the big name column manufacturers are scrambling to produce copy-cat columns. Will be interesting to see. Anyone else been working with these columns? I think this is the biggest btreakthrough in HPLC column technology in 25 years...thats how long I've been doing LC.

Thank you Supercritical,

Is any way you can identify yourself to us, we would like to add you to our database - we can send you our monthly updates.


I believe that there are just a few people here who have used our column (I know at least four), but we are still trying to deliver our message.

That's one of the boldest sales pitches I've read on here..

JA,

I can assure you that nobody at SIELC posted the first message (on a Bible, under oath, on my helath or whatever...LOL) but you are free to express your opinion. Unfortunately Supercritical has no "personal" information with email address, which might show that he is not associated with our company.

SEILC_Tech: Yes I am already on the mailing list! Thanks!

No I have nothing to do with the company that manufactures these columns. However, I have done LC for 25 years and I do believe this technology is the biggest breakthrough in HPLC columns that I have seen. This is my opinion, and I would like to hear other comments. As I stated, any column manufacturers in the know are definately pursuing this technology right now. This technology has overcome problems with traditional columns including those with embedded polar groups in regards to analyzing polar, ionic and neutral components in one quick easy method. This has been a limitation of HPLC in the pharmacuetical industry (probably the biggest end user of analytical and prep columns) ever since HPLC was invented. Time will tell.

15 years of method development/validation in the Pharma business, and I also am a believer.

Had no success developing a small molecule method (8 component matrix) that would provide any resolution for my compound of interest. I spent approximately 1 month evaluating various columns/buffer on 2 LC's.

After a week of using the column, a method was developed. After a 2 week evaluation/qualification it was determined that the method was satisfactory for cGMP validation upon demonstration of batch to batch variability (or hopefullylack there of).

I do not work, nor do I know anyone who is associated with SIELC. Feel free to contact me @ scook@rxkinetix.com

Anyone of you have any experience analyzing peptides with this particular column and have acheived good separatiion of peptide impurities from its API?

Sounds like an intersting column but who is the manufacturer of this column?I can search but if you can tell me I can save my time:)

Thanks for the great news!

Ananda

Dear Ananda,

You can learn more about Primesep technology at

www.primesep.com

We will need more information on the size of your peptide (molecular weight, fragments, etc.) and your detection technique. You can check our method development guide for column and mobile phase selection:

http://www.hplcmethoddevelopment.com/

You can contact us at mail@sielc.com to discuss your particular application or check our library of methods (you can sort it by date, by compound or by application):

http://allsep.com/Applications_By_Column.php

I can understand being enthuisastic after solving a tough separation. But it seems a bit of an overstatement to imply that this is the first column that will separate "polar, ionic and neutrals", how ever polar and neutrals are defined in this context.

I can provide numerous examples of such separations on prior art columns. For example, a great number of columns-Speherisorb ODS 2, Aquasep, and other hydrophilic columns- will separate aromatic difunctional acids along with some of their sulfonated analogs. While I never had the need to do so, esters of these acids would separate in the same run. (Anal.Chem. 63(1991)1251, for example.)

I am going to need more specific data before I agree that this column is a more significant advance than more inert silica, sterically hinderd ligands, base stable packing and no doubt others .

Bill,

I can understand your skepticism about this approach, If you (or anybody else) on this board have a tough separation we can try to develop the method and compare the results with any other column. The key in our technology is independent control for polar and hydrophobic compounds. You can enhance or suppress interaction with a simple modification of the mobile phase. Assuming that compounds have slight difference in hydrophobicity and polarity (ionization), by modifying both ion strength (and nature) and organic strength of the mobile phase, you can "pull apart" a lot of critical pairs and very often with isocratic conditions. The advantage of this approach is obvious in quantitation and preparative chromatography was by modification of two parameters of the mobile phase you can control the elution order of compounds.

Check this power point presentation for a few good examples:

http://allsep.com/brochures/SeparationD ... pounds.pdf

Another advantage of this approach is that you can use one column in several modes: RP, ion-exchange, ion-exclusion, normal phase, HILIC and mixed-mode. Here is another link with examples:

http://allsep.com/brochures/UniversalSt ... yPhase.pdf

I really would like to understand the origin of the enthusiasm. What is easier? What is more complicated? Does the level of complication in the interaction mechanism present a problem or an opportunity?

When I did hands-on applications work myself (in the last century), I worked with a C18 column full of silanols that was so bad that barely anybody wanted to touch it. However, I was very familiar with it and I could get wonderful results with this column independent of the sample or the pH. To some degree, this column was similar to these mixed-mode packings. Many times, I could do separations that were difficult on a better C18. Are these mixed-mode things similar?

What is easier? What is more complicated? Does the level of complication in the interaction mechanism present a problem or an opportunity?

Doesn't matter to me. Primesep columns can do what no other column can do. Read what I said above. The column interactions are completely predictable if you understand the column chemistry and the chemistry of your sample components. I have found that I have much more control over the separations with these columns....a good thing for all chromatographers.

I've fought with difficult separations using ion pair reagents, tandem ion exchange/ RP columns, multiple methods, etc... These column can handle all that stuff & more. I do a lot of prep too, I can't mess around with Ion pair. Plus ion-pair goofs up the MS. Goodbye PIC reagents!

Look through the posts on this site and, and see all the questions about ion pair, organic acids, IEC, bases & amines, etc...!!! Lots of problems here for chromatographers. My suggestion is, if you got these problems, take a look at the Primesep line. I know that this may sound like a sales pitch, but it is not. This is a forum for chromatographers to spread knowledge and help one another, and that is my intent.

SIELC:

Thanks for the information. I will keep thisinformation handy, even the page of everybodys comments here. for future reference. So far most of our peptide methods have been validated. Anyway, thanks again for the information.

Ananda

The purpose of this note is to be constructive, not critical......

Successful scientists are by nature skeptical folk. So a headline like what started this thread invites a skeptical response unless the claims are supported by data or explanation. There has been little of either.

As I have pointed out, this is certainly not the only column that can separate the classes of compounds claimed. So that claim by itself did nothing to diminish my skepticism. It was stated, however, the retention of these classes can be independently(easily, predictably???) controlled. That statement began to kindle some interest. If someone would tell us how it works, how its chemistry is different, how retention of compound classes is independently affected and specifically a separation it can do easily where traditional columns have failed, then I would see for myself what a "breakthrough" this technology might be. I think that forum participants would consider such information "science" not "advertising" and hence it would be acceptable (speaking for myself only).

Bill,

I might try to explain mechanism of retention and elution control but it might take to much space on this thread. I think it is more productive that you try to download all our brochures, newsletters and posters. If you would like we can add you to our distribution list and in this case you will receive all updates. Check the following link for Primesep literature:

http://allsep.com/Brochures_Home.php