By Monica Romero on Thursday, November 6, 2003 - 06:16 am:

Dear Scientists,

I am currently searching databases, papers and methods to find a substitute of the surrogates I was using (Method EPA 8100 recommends the use of 1-fluoronaphthalene, and 2-fluorobiphenyl). 1-fluoronaphthalene overlaps with naphthalene in the chromatogram so it's not convinient (I am using GC/FID and the colum is a HP-5 5% diphenyl & 95& dimethylpolysiloxane, non polar) and 2-fluorobiphenyl comes a bit after naphthalene and ideally for my purposes the surrogate should come slightly before naphthalene to check up for any loses in the concentration method after extraction. As I stated I did already some searching and still haven't found 'Mr. ideal' surrogate. Does anyone can help and let me know if you know of a good substitute I may use? I appreciate your help.

Monica Romero

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By Monica Romero on Friday, November 7, 2003 - 10:18 am:

Some people somewhere else suggested to me the use of deuterated analogues but EPA method 8100 doesn't recommend the use of deuterated analogues due to coelution problems.

The problem of selection is that I need to be picky about the polarity of the possible surrogate considering the polarity of my column (HP5 is non-polar but more toward intermediate type). There are some attractive halogenated compounds (for example Decafluorobiphenyl)for the purpose but then the question of
how much the increase in the number of halogens on the compound increases its polarity remains unclear to me. And the other question is: How important is that the surrogate is a doble-ring compound (similar as naphthalene)? I found that there are one-ring compounds that may fit the purpose but I am not sure if I can use this type.

Hope I may have some answers for my questions.

Thank you

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By Robert Michels on Wednesday, June 23, 2004 - 07:39 am:

For HPLC, Try 6-Methylchrysene...works great and comes out before benz(b)fluoranthene

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By Edelvio de Barros Gomes on Friday, June 25, 2004 - 06:12 am:

Dear Researchers

I am striving to excel in chromatographic methods to assess soil pollution by PAH. The current EPA 8100 technique suggest FID detector. I have GC-MS sistem with TCD detector. What are the risks by utilizing this detector?

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By jeffo on Monday, August 23, 2004 - 01:02 pm:

monica,
we use ptp as a surrogate for our PAH analysis.
we follow epa 8270