100% aqueous mobile phase

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

5 posts Page 1 of 1
Dear all ,
lately my lab have received a new method for tobramycin determination, this new method don't use derivatization as USP did , its mobile phase is 100% buffer solution of pH 10 , on C18 column , and wavelength , 210 nm , so my questions if you can help me , did anyone experienced a 100% aqueous mobile phase ?!! i have read that it may cause column collapse , secondly what is your opinion in injecting tobramycin as is without derivatization ?
regarding that USP method for determination of tobramycin uses derivatization with 4-floro,2,4-dinitro benzene
Many C18 columns nowadays can handle 100% aqueous mobile phase. pH 10 is a bigger problem, but i'm quite sure columns are available for that.

Which particular column does the method mention?
Hi Rndirk,
it is X-Bridge (waters)
I agree with the previous post. There are columns out there that can def handle 100% aqueous. Not sure about the ph though. Also not sure the xbridge can handle 100% aqueous. It is a pretty tough column but what you want is a t3 c18 column from waters or anything that says aquasil from other manufacturers. I believe phenomenex also has Luna c18 columns but I forget the name of their 100% aqueous line of columns. Just note that the xbridge and other c18 columns will seem fine for a little while if you try 100% aqueous but over time you will experience dewetting and column collapse of the stationary phase. So I would highly recommend looking into the columns that can handle 100% aw for long periods of time
Many methods use 100% aqueous mobile phases and conventional ODS columns (non-"aqua-ODS"):
https://extranet.edqm.eu/4DLink1/4DCGI/ ... w/mono/611
https://extranet.edqm.eu/4DLink1/4DCGI/ ... w/mono/685

In order to prevent the stationary phase dewetting, often it is enough to pre-wash the ODS column with a water/organic eluent, then switch to the 100% aqueous mobile phase without stopping the flow, and then proceed with the analysis without stopping the flow.
5 posts Page 1 of 1

Who is online

In total there are 8 users online :: 1 registered, 0 hidden and 7 guests (based on users active over the past 5 minutes)
Most users ever online was 599 on Tue Sep 18, 2018 9:27 am

Users browsing this forum: Google [Bot] and 7 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, Environmental, (Bio)Pharmaceutical, Bioclinical, Liquid Chromatography, Gas Chromatography and Mass Spectrometry.

Liquid Chromatography

Gas Chromatography

Mass Spectrometry