Lack of evidence of dilution history-dependence upon solute aggregation in water

[geni]

Homeopaths having been having fun with the study that suggsted that in certain situations the further diluted a substance, the more its molecules tend to clump together. Well it turns out someone tried to repeat the work.

http://www.rsc.org/CFmuscat/intermediate_abstract.cfm?FURL=/ej/CC/2002/b207135e.PDF

[JamesM]

Fascinating. How did you find that, Geni? Annoyingly, Web of Knowledge completely missed this as citing the Geckeler paper.

[geni]

Originally posted by JamesM
Fascinating. How did you find that, Geni? Annoyingly, Web of Knowledge completely missed this as citing the Geckeler paper.

Wikipedia, someone added it to the homeopathy page.

[Mojo]

Originally posted by geni
Homeopaths having been having fun with the study that suggsted that in certain situations the further diluted a substance, the more its molecules tend to clump together.
I just got this mental image of a molecule shouting "form the wagons into a circle!":D

Looks a bit like clutching at straws even if it had been true. How could they possibly know if they'd retained the bit with the clump in it? And anyway, if they managed to retain it, wouldn't that make the solution less dilute and therefore (according to homeopaths) less effective?

[Rolfe]

That's interesting. I always doubted that study, because I've never seen any evidence of the effect. I often do quite a lot of serial dilutions of high-reading plasma samples in order to get them on to the linear-reading part of an analytical assay. We jokingly describe a very high-result sample as "needing homoeopathic dilutions to get an answer". The thing is, this exercise always demonstrates a linear relationship between dilution factor and measured concentration. It would be invalid otherwise. I suppose one could postulate that they were talking about much weaker dilutions, but it didn't really fly for me.

Of course, it never provided any support for homoeopathy anyway, and the fact that homoeopaths cited it only showed how poor their grasp of simple logic really is. Oh, it works because a few of the aliquots aren't as dilute as we thought they were! No, I don't think so.

Rolfe.

[MRC_Hans]

The clumping (or whatever we might call it) would not make the response non-linear, if it existed. It would just change the normal distribution of the result (making it more stochastic). Like many of the other straws that homeopaths grab at, this one wouldn't carry them even if it happened to be true!

Hans

[KingMerv00]

Part of what I do for a living is make solutions of varying concentrations and then running them through different instruments. The responses are greater for higher concentrations and less for lower concentrations. If molecules "clumped" (friggin' tripe) the exact opposite would be true.

If they were right, ALL OF CHEMISTRY WOULD BE VASTLY VASTLY DIFFERENT.

Ugh...nevermind.

[Anders]

I'm surprised someone even bothered to repeat the experiment, just because it's so stupid. But I'm glad they did.