By Anonymous on Tuesday, October 29, 2002 - 08:14 am:
In our lab we currently use a 1090 HPLC with fluorimetric detection for PAH’s analysis.
Recently we are involved with analysis of coumarinic anticoagulants with the same instrument; for this determination we have used a buffer containing ammonium acetate (50 mM), acetic acid (2 mL/L) and triethylamine (2 mL/L). Flushing the buffer channel with water was daily standard operation at the end of analytical determinations.
Returning to PAH’s analysis a problem arised: the peak of benzo(a)pyrene in standard solution show a pregressive decay (both area and heigth). This phenomenon is observed only for benzo(a)pyrene; the others PAHs show usual repeatability.
Note that “buffer channel” is the channel used with water in PAH’s analysis.
There is a possible interaction between triethylamine residue and stationary phase?
Another way to explain this selective behavior for benzo(a)pyrene?
Any input are greatly appreciated.
Thanks in advance
By Anonymous on Tuesday, October 29, 2002 - 08:24 am:
Is your standard fresh?
By adil on Monday, November 4, 2002 - 02:06 am:
did u validate ur method initially
By adil on Monday, November 4, 2002 - 02:12 am:
u can try by eleminating try ethylamine from the buffer
and see the peak pattern
just to trackthe interaction of triethylamine with st. phase