Page 1 of 1
Urea analysis HPLC/ C18 column
Posted: Mon Oct 28, 2013 5:34 pm
by ap.floriano
Does anyone know a method to determine urea in aqueous solution with a C18 column?
Re: Urea analysis HPLC/ C18 column
Posted: Mon Oct 28, 2013 9:17 pm
by tom jupille
4,250,000 of them according to Google: +urea +HPLC +C18".
Re: Urea analysis HPLC/ C18 column
Posted: Thu Feb 06, 2014 8:26 pm
by ph/Amr Tarek
Urea cannot be retained by C18 columns ( reversed columns )
This is an official method to analyze urea by HPLC :
1) column : Zorbax RX SIL 4.6 × 150 mm
2) mobile phase : (acetonitrile : 0.02M K2HPO4 pH 7.2) (90 : 10)
3) detector : UV 210 nm
4) flow rate : 1 ml/min
Urea retention time is about ( 3 - 4 ) min
Note : Zorbax RX SIL column should be flushed with THF befor equilibrating by the mobile phase .
ph/Amr Tarek
Instrumental Unit Head at Otsuka Pharmaceutical Company
Re: Urea analysis HPLC/ C18 column
Posted: Thu Feb 06, 2014 10:58 pm
by Vlad Orlovsky
Re: Urea analysis HPLC/ C18 column
Posted: Fri Feb 07, 2014 4:36 pm
by dap
Hello!
Ion pair agent buffered solution may increase retention time. Sodium hexanesulfonate seems to be a good choice. Columns with polar stationary phase such as NH2 or Silica usually show wavy baseline imho.
Re: Urea analysis HPLC/ C18 column
Posted: Fri Feb 07, 2014 4:38 pm
by Vlad Orlovsky
Urea is a neutral compound, ion-pairing reagent is going to do nothing
Re: Urea analysis HPLC/ C18 column
Posted: Fri Feb 07, 2014 5:20 pm
by dap
Sorry if so.