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ortho-ortho chelate


22 Sep 2023
Hi, I asked the seller about the chelation of this product and he told me that it is ortho-ortho chelated. Is there such a chelate or if so, what is the pH value of this chelate?
Most of the iron chelates work around EDTA or chemically similar chelation. 'Ortho' describes the geometry by which the iron atom is held in place by the chelator - this comes in four possible flavours: ortho-ortho, ortho-para, para-ortho, para-para. Ortho-ortho is the most stable so that's generally the one you want. The pH stability of this specific iron chelate depends on what the chemical chelator is - common choices would be EDTA, DTPA, and EDDHA. An online search didn't help me find out which chelator ATTACK-Fe uses but if I had to guess it would be EDTA which is probably fine for most purposes. You should ask the seller something like, "does it use EDTA as a chelator?"
Ortho-ortho is more of a structure of said chelate, rather than the chelate itself. To be honest it's way above my pay grade, but generally these different structures are associated with eddha fe.
The package labeling doesn't mention eddha, so I'm at a loss.
Anyway... here's a bit of info on said subject.

"EDDHA chelates always consist out of a mixture of three different structures. The following figure gives an overview of the different shapes.
Iron chelate for plants

Of the different EDDHA structures shown above, the top one is most stable. It’s called an ortho-ortho EDDHA. The other two types are called ortho-para and para-para EDDHA. Since all types of red iron (EDDHA) on the market contain one of the above-mentioned structures.

There's more..

I'm still clueless, hopefully a chemist will chime in.

Edit: Andy sums it up pretty well.
'Para' means 'opposite' and refers to the location of the (green) -OH group coming off the hexagonal ring that connects to the rest of the molecule. 'Ortho' means 'next to' and shows the (red) -OH coming off the hexagonal ring next to the piece connecting to the rest of the molecule. The other possible remaining geometry where the -OH connects between the ortho and para sites is called 'meta' and is not part of the chemistry of these chelates. Neither EDTA nor DTPA contain these ring structures, so it isn't really sensible to speak of 'ortho-ortho' EDTA (or DTPA) and suggests this chelate is either EDDHA or EDDHSA, probably EDDHA - you could tell from the colour: EDDHA is pink, EDDHSA is brown. I'm not a chemist, but I pretend to be one sometimes on UKAPS. ;)
Cheers for the explanation @Andy Pierce

Did a bit more digging and found a Turkish site selling said product, it lists the chelate as;
"Komplekleme (şelat): Sarsapogenin + Organik Asitler + Diğer Biyo Kompostlar" or by the powers of Google translate;
"Complementation (chelate): Sarsapogenin + Organic Acids + Other Bio Composts"

I'm assuming they mean Sarsasapogenin? Which is named after sarsaparilla and derived from Saponin.

This new found information makes me non the wiser unfortunately.