Advertisement

r.i.p. betty hamilton

Discussions about HPLC, CE, TLC, SFC, and other "liquid phase" separation techniques.

4 posts Page 1 of 1
genetics approaches. Gene expression pro- mosome in this way, in effect giving the cardiovascular disease. Egr-1 is an essen
.., i have been reading this novel book about the famous TWILIGHT stuff. I love the movie at first but when I came to read the book I was really disappointed because of there are lot of
ages you to sit calmly, be mindful, and enjoy your- many cocktails, from Shirley Temples to Tequila 2 In a large bowl, combine the salmon, bread crumbs, oats, onions, dill, parsley, paprika
When you're doing your screen captures, are you using full screen, or a reduced size? I'm suspecting a reduced size, since the outcome is bad If your monitor screen's full resolution is say 1280 x 80

I should add that the mobile phase contained 10% acetonitrile at all times to reduce hydrophobic effects. However, perhaps 10% isn't enough, and there is a hydrophobic retention mechanism in addition to ion exchange.

You are using two completely different columns with completely different pore sizes. The 4.6 mm i.d. column contains 500 A packing, while the 2.1 mm column contains a 1500 A packing. My bet is that the later elution on the 4.6 mm column is for the most part due to the smaller pore size, which results in a roughly 3-fold higher surface area and thus larger retention.

There could be other factors also, but you did not give the complete method, incluing the flow rates for the two columns. However, the pore size is likely to be the largest factor.

Thanks for the response.


The flow rate for the 2.1 mmID was 200 microliters/min

For the 4.6 mmID, 1 mL/min.

I should add that the separations were done on different instruments. The 4.6 mmID was run on a Perkin Elmer 410. The 2.1 mmID was run on HP 1050. Both runs at ambient temperature. Everything else (including mobile phase) identical.
4 posts Page 1 of 1

Who is online

In total there are 19 users online :: 2 registered, 0 hidden and 17 guests (based on users active over the past 5 minutes)
Most users ever online was 4374 on Fri Oct 03, 2025 12:41 am

Users browsing this forum: Amazon [Bot], Semrush [Bot] and 17 guests

Latest Blog Posts from Separation Science

Separation Science offers free learning from the experts covering methods, applications, webinars, eSeminars, videos, tutorials for users of liquid chromatography, gas chromatography, mass spectrometry, sample preparation and related analytical techniques.

Subscribe to our eNewsletter with daily, weekly or monthly updates: Food & Beverage, Environmental, (Bio)Pharmaceutical, Bioclinical, Liquid Chromatography, Gas Chromatography and Mass Spectrometry.

Liquid Chromatography

Gas Chromatography

Mass Spectrometry