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Subject: Compost Teas: 24 hour, EM, IM, BD & fermented plant extracts

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  • From: "William F. Brinton" <wbrinton AT woodsend.org>
  • To: compostteas AT lists.ibiblio.org
  • Subject: [Compostteas] - Chromatography- Cautions and Funs
  • Date: Mon, 15 Jul 2002 12:14:37 -0700

I noticed the comments about Pfeiffer chromatography and wanted to shed some light - and caution - after years of experience.

The filter paper chromatography test proposed will not work without suitable reagents as any chromatography chemist will tell you. In fact, Pfeiffer's method is quite an unconventional use of chromatography. To cause a mutual separation of molecules w/o the proper preparation as proposed by Elaine in the last email would be like catching water (the humus
molecules)  on a screen (the paper).  Well- you will get a yellowish blob on the paper.

With normal chromatography one causes separations by combining substrate (i.e. silica-gel surface or similar in paper )    and solvent (organic solvents that enhance/retard solubility of specific compounds)   AFTER a test compound is applied to a surface.  Pfeiffer turned it around and used a variable supply of compound (i.e. the compost extract)  wicked up into the paper continuously (instead of solvent wicked up through the compound applied as a dot on the paper or surface).  It's amazing with this total violation of chromatography principles it actually worked - some believe - but it also explains why conventional chemists never really took it seriously. Furthermore, to be reproducible requires we found extraordinarily tight controls of methodology and environmental conditions that most persons are not capable of accomplishing. Thus, you will find huge differences in the same test sample performed at differing locations by differing persons.  Just change the temperature slightly and the whole reaction (and colors produced)  are altered.  The images shown on the link website I can tell you are just one of many possible types obtainable from the same sample.

Readers might be interested in by book chapter paper showing chromatographic procedural steps with humus-compost extracts and the precautions needed to obtain reliable results. We did show good rank-order correlation of chroma form with Humic:fulvic ratios in extracts, for example, which means you can infer something about humus conditon from the actual forms. -- Brinton, W , R Parnes (1983)  A Qualitative Method for Assessing Humus Condition. in Sustainable Food Systems ed. D. Knorr, AVI Publishers. -- After that project Dietrich Knorr's group ad Univ. Delaware did a variety of rank-order studies with pfeiffer's method on plant tissues with interesting results (several were published in a variety of journals).

One advisory note- the chemistry of AgNO3 reactions along with the requisite alkaline extract of soil and humus is very  very complex. The oddly serendipitous combination of the steps and weird chemicals that Pfeiffer selected is quite interesting. Silver for example is photo chemically sensitive (differing colors  based on chemistries involved)  plus is a powerful oxidizing agent (and antiseptic)  which changes colors based on the ORP state of the organic molecules contacted, while causing them to be oxidized during the actual process. Plus it forms strong complexes with humus molecules (try titrating humus against AgNO3 and you'll see).   Thus, the chromatographic separation in Pfeiffer's procedure is by accident largely caused by silver's complexes blocking the paper pores (also a violation of modern procedures of chromatography)!. which causes a kind of filtration of lower molecular weight compounds that move past - or try to get past- the complexes.  Several of the images seen on the web link provided at http://lists.ibiblio.org/mailman/listinfo/compostteas  give evidence of this paper pore blocking which it could be argued is an artifact of the method. Any distorted image is pore blocking of paper if not excessive drying.

If you are still interested after these precautions, please have fun!

Will Brinton
 
 
 
 
 



 
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William F. Brinton, Jr.
Woods End Research
PO Box 297
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  • [Compostteas] - Chromatography- Cautions and Funs, William F. Brinton, 07/15/2002

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