By khcha on Monday, April 29, 2002 - 04:12 am:
Hellow everyone?
I have an difficulty in analysis of ceftiofur metabolites(desfuroylceftiofur and others) in milk sample.
Do you have any experience for the analysis of ceftiofur metabolites in milk sample?
Please give your advice for me to solve problem!
l hope your help!
By Anonymous on Monday, April 29, 2002 - 05:18 am:
"Please give your advice for me to solve problem!"
Your problem as you describe it....
"I have an difficulty in analysis"
It is virtually impossible to offer help or advice when so few (none in this case) details are offered. How about little more information. There are many people who frequent this message board who are willing to help if they can.
By Anonymous on Monday, April 29, 2002 - 09:46 am:
This is a beta lactam and there are may published articles regarding its analysis. Start with a literature search restricted to the Journal of Chromatography and you will retrieve many articles. Also search with Google.
By khcha on Monday, April 29, 2002 - 06:42 pm:
Ceftiofur analysis is very easy in milk sample.
But it's metabolites Desfuroylceftiofur(DFC) analysis very difficult to me. l have many literature for ceftiofur analysis, but DFC analysis in milk sample is rare. Do you have experience for analysis DFC with iodoacetamide
derivatization method in milk sample.
By curbiro on Tuesday, April 30, 2002 - 12:31 pm:
What kind of problems are you having?Do you mean band broadening and tailing?
I´m trying to analyze b-lactams too, and perhaps we could talk about it ...
By khcha on Tuesday, April 30, 2002 - 05:08 pm:
DFC recovery did not good without derivatization in milk sample. Therefore, I tried to DFC derivatization with iodoacetamide. At first, I conformed the derivatized desfuroylceftiofur acetamide(DFCA) peak change the spiking concentration. The result showed that some peak increased the responese as increasing the concentration. But. l can't sure that the peak is really DFCA. Finally, I tried to conform the peak with LC/MSD. But DFCA mass peak(M+H 487 m/z) and possible fragment ions does not appeared.
I'm now stop the experiment and review the data.
Thanks your attention!
By Anonymous on Monday, March 22, 2004 - 07:16 pm:
Hi Khcha,
Could you tell me how U spike the standard into the sample? Did you start spike with Ceftiofur or Desfuroylceftiofur? Then we may talk further about this.