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PAH analysis problems (Mobile phase)

Posted: Thu Apr 23, 2009 1:11 pm
by wrighty
Hi all,

I am developing a method for PAH analysis by HPLC and have come across a few problems.

The main problem is lack of acetonitrile :roll: . i tried replacing this with methanol but the pressure of the column shot through the roof. I then tried using a 70% acetone solution (in water) but have noticed that the slightest agitation of the solvent reservoir causes a horde of tiny bubbles to form around the frit and pulling air into the system. Has naybody else experienced this?

In addition i am trying to source fluoresence (spelling?) bandwidths for the following PAH's:

Benzo(g,h,i)perylene
Benzo(a)anthracene
Chrysene/Triphenylene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Indeno(1,2,3-cd)pyrene
Dibenzo(a,h)anthracene

Any help/ pointers would be greatly appreciated.

Many thanks

Steve

Posted: Thu Apr 23, 2009 1:41 pm
by Bryan Evans
You may want to try Cadenza CL-C18 for this application:
http://www.imtakt.com/TecInfo/TI265E.pdf

Advantages to this column for this application include:
a). Silanol activity (useful for this separation)
b). 25-50% less back pressure than conventional 3um columns
c). Very high efficiency at low flow rate

We have customers using 250x4.6mm, 3um with Water:MeOH
mixtures - no problem. You can reduce your flow rate and stay
within the pressure limits of your LC.

This data shows Water:MeOH mixture for 500x4.6mm (3um) column:
http://www.imtakt.com/TecInfo/TI148E.pdf
http://www.imtakt.com/TecInfo/TI149E.pdf