Homeopathy: Rustum Roy drops the bomb

[Pipirr]

Rustum Roy's eagerly anticipated article on homeopathy is here.


Homeopathy
Volume 96, Issue 3, July 2007, Pages 175-182
The Memory of Water

Quote:

The defining role of structure (including epitaxy) in the plausibility of homeopathy

Manju Lata Rao, Rustum Roy, Iris R. Bell and Richard Hoover

Abstract

The key stumbling block to serious consideration of homeopathy is the presumed “implausibility” of biological activity for homeopathic medicines in which the source material is diluted past Avogadro's number of molecules. Such an argument relies heavily on the assumptions of elementary chemistry (and biochemistry), in which the material composition of a solution, (dilution factors and ligand–receptor interactions), is the essential consideration.

In contrast, materials science focuses on the three-dimensional complex network structure of the condensed phase of water itself, rather than the original solute molecules. The nanoheterogenous structure of water can be determined by interactive phenomena such as epitaxy (the transmission of structural information from the surface of one material to another without the transfer of any matter), temperature–pressure processes during succussion, and formation of colloidal nanobubbles containing gaseous inclusions of oxygen, nitrogen, carbon dioxide, and possibly the remedy source material.

Preliminary data obtained using Raman and Ultra-Violet–Visible (UV–VIS) spectroscopy illustrate the ability to distinguish two different homeopathic medicines (Nux vomica and Natrum muriaticum) from one another and to differentiate, within a given medicine, the 6c, 12c, and 30c potencies. Materials science concepts and experimental tools offer a new approach to contemporary science, for making significant advances in the basic science studies of homeopathic medicines.

You may note the rampant speculation, and overuse of 'preliminary data'. However, what is most extraordinary to me is that the entire journal edition is devoted to 'the memory of water'. It's as though the Nature committee's debunking of Benveniste never happened.

Go here for more discredited nonsense, starring such luminaries as Peter Fisher, Lionel Milgrom and Louis Rey. Madeleine Ennis is conspicuously absent.


Rustum Roy's upcoming article has also been discussed in these threads :
http://www.internationalskeptics.com...ad.php?t=82393
http://www.internationalskeptics.com...ad.php?t=87421

[Mojo]

I see he's running his strawman argument again:

Quote:

The key stumbling block to serious consideration of homeopathy is the presumed “implausibility” of biological activity for homeopathic medicines in which the source material is diluted past Avogadro's number of molecules.

The key stumbling block is that it doesn't work.

[Zep]

Has he got any actual reliable data? Or is it all just rampant gobbledygook and speculation.

[pgwenthold]

Rustom Roy is a pretty big loon. I remember back in the early 90s he was big on eliminating the peer review system, in the name of "young scientists" who apparently couldn't get their work published due to the biases of the old guys. Oddly enough, I didn't meet too many of them as I began my career. Roy postulated a system in which young people only needed to get a senior colleague endorsement of their work for it to be published. It never caught on (unless he did it in his own journal that he started).

[JoeEllison]

The "key stumbling block" is the assumption that the foundations of modern chemistry are solid? Really?

[Mojo]

Originally Posted by Pipirr

Go here for more discredited nonsense, starring such luminaries as Peter Fisher, Lionel Milgrom and Louis Rey. Madeleine Ennis is conspicuously absent.

I see Milgrom is still talking about "macro-entanglement" as if it's an actual mechanism rather than a metaphor:

Quote:

In order to fully comprehend its therapeutic mode of action, homeopathy might require both ‘local’ bio-molecular mechanisms, such as memory of water and ‘non-local’ macro-entanglement, such as patient–practitioner–remedy (PPR) descriptions.

[Mojo]

Originally Posted by pgwenthold

Rustom Roy is a pretty big loon. I remember back in the early 90s he was big on eliminating the peer review system, in the name of "young scientists" who apparently couldn't get their work published due to the biases of the old guys. Oddly enough, I didn't meet too many of them as I began my career. Roy postulated a system in which young people only needed to get a senior colleague endorsement of their work for it to be published. It never caught on (unless he did it in his own journal that he started).

His journal Materials Research Innovations uses something called "super peer review", which it claims is "especially suited for the publication of results which are so new, so unexpected, that they are likely to be rejected by tradition-bound journals".

It doesn't seem to be of much use to the "young scientists" referred to above, though. According to this page, also about Materials Research Innovations:

Quote:

Super peer review is based on reviewing the authors, not the particular piece of work. Moreover, that review can be done easily and on objective criteria. What is the major criterion? That the author (at least one) shall have published in the open, often peer-reviewed (!!) literature, a large (30-50 papers) body of work.

So in fact it benefits people like, er, Rustum Roy.

[Pipirr]

It's like vanity publishing for scientists.

[JoeEllison]

I'd forgotten about the "Super-Duper Groovy Peer Review"...

[pgwenthold]

Originally Posted by Mojo

His journal Materials Research Innovations uses something called "super peer review", which it claims is "especially suited for the publication of results which are so new, so unexpected, that they are likely to be rejected by tradition-bound journals".

It doesn't seem to be of much use to the "young scientists" referred to above, though. According to this page, also about Materials Research Innovations:


So in fact it benefits people like, er, Rustum Roy.

Yeah, that's what I was thinking of. The way it helps young scientists is that they could get a "senior colleague" to add their name to the author list and therefore get it published.

Maybe it wasn't done to help young scientists, but this is the way young scientists could get into the thing. It was a long time ago when he was talking about it.

Everyone I knew just sort of rolled their eyes.

[Rolfe]

You used to be able to get whole Homeopathy articles free online, but not now. I'm damned if I'm paying for that!

But looking at the abstract, I think we've seen his data already.

Quote:

Preliminary data obtained using Raman and Ultra-Violet–Visible (UV–VIS) spectroscopy illustrate the ability to distinguish two different homeopathic medicines (Nux vomica and Natrum muriaticum) from one another and to differentiate, within a given medicine, the 6c, 12c, and 30c potencies.

Four slides in the middle of this.

The UV spectroscopy is just wrong. The spectrum he presents for ethanol just is not the UV spectrum of ethanol, period. He then seems to be saying that the potentised remedies are less absorbent than the solvent. I could see no data supporting his contention that he could tell different potencies or different remedies apart.

If in fact what he says is true (that ethanol has significant UV absorbance at 320nm which is eliminated when the ethanol is used as the solvent for the production of a potentised remedy), anyone with a spectrophotometer capable of reading at that wavelength would be able to see this easily for themselves. And be queueing up to apply for the million bucks. I could do it myself (I suspect - modern analysers are so specialised compared to the simple spectrophotometers we used to use that I'd have to think about how....). The problem is that it all falls apart when you simply observe that ethanol does not in fact have significant UV absorbance at 320nm.

I couldn't understand the Raman spectra he presented in that slide show, but they all seemed noisy, and the scales were inconsistent. Given that he has messed up an ordinary UV spectrometry reading of ethanol quite as comprehensively as he has, I have little confidence in anything he presents in a more complex field.

Rolfe.

[Pipirr]

The library website at my academic institution has taken this opportunity to fall over, so I can't confirm if it's the same data. But probably it is.

[Deetee]

Originally Posted by Rolfe

You used to be able to get whole Homeopathy articles free online, but not now. I'm damned if I'm paying for that!

But looking at the abstract, I think we've seen his data already.

Four slides in the middle of this.

The UV spectroscopy is just wrong. The spectrum he presents for ethanol just is not the UV spectrum of ethanol, period. He then seems to be saying that the potentised remedies are less absorbent than the solvent. I could see no data supporting his contention that he could tell different potencies or different remedies apart.

If in fact what he says is true (that ethanol has significant UV absorbance at 320nm which is eliminated when the ethanol is used as the solvent for the production of a potentised remedy), anyone with a spectrophotometer capable of reading at that wavelength would be able to see this easily for themselves. And be queueing up to apply for the million bucks. I could do it myself (I suspect - modern analysers are so specialised compared to the simple spectrophotometers we used to use that I'd have to think about how....). The problem is that it all falls apart when you simply observe that ethanol does not in fact have significant UV absorbance at 320nm.

I couldn't understand the Raman spectra he presented in that slide show, but they all seemed noisy, and the scales were inconsistent. Given that he has messed up an ordinary UV spectrometry reading of ethanol quite as comprehensively as he has, I have little confidence in anything he presents in a more complex field.

Rolfe.

His claimed ability to distinguish homeopathic preparations by spectroscopy was the thing that made my jaw drop too. I don't know enough about the field to comment, but if this technique is reliable, then homeopaths should have little difficulty identifying their remedies and potencies - one would think that from a quality control perspective this technique would be accessible and adopted/enforced by homeopathic remedy manufacturers as a matter of course.

Also, its a sure fire $million dollar challenge winner.

So why has this not happened? (rhetorical question)

[Blue Wode]

More…

Quote:

Guest editor Professor Martin Chaplin of the Department of Applied Science at London South Bank University, remarks: “There is strong evidence concerning many ways in which the mechanism of this ‘memory’ may come about. There are also mechanisms by which such solutions may possess effects on biological systems which substantially differ from plain water.”

-snip-

Commenting on the special issue, Professor Chaplin said: “Science has a lot more to discover about such effects and how they might relate to homeopathy. It is unjustified to dismiss homeopathy, as some scientists do, just because we don’t have a full understanding of how it works.” In his overview he is critical of the “unscientific rhetoric” of some scientists who reject the memory of water concept “with a narrow view of the subject and without any examination or appreciation of the full body of evidence.”

Professor Chaplin and Dr Peter Fisher, editor-in-chief of the journal, agree that the current evidence brings us a step closer to providing an explanation for the claims made for homeopathy and that the memory of water, once considered a scientific heresy, is a reality. “These discoveries may have far reaching implications and more research is required,” comments Dr Fisher.

http://www.eurekalert.org:80/pub_rel...-tmo080107.php

[juryjone]

Originally Posted by Deetee

Also, its a sure fire $million dollar challenge winner.

So why has this not happened? (rhetorical question)

They could take several different approaches to proving homeopathy:

1) Prove that a properly controlled homeopathic remedy cures the proscribed disease in a properly controlled double-blind experiment;

2) Prove that "like cures like", regardless of the potency of the remedy;

3) Prove that some of the substance remains in the solution after properly controlled dilution, which flies in the face of Avogadro's limit and modern chemistry.

Only one of these can be tested by the MDC, since Randi cannot do proper medical trials. And that is the approach taken here - proving that something detectable remains in the solution after all the dilution. It seems that they are positioning themselves to apply for the challenge - otherwise they'd just try to prove the stuff works, without regard to the chemistry behind it.

It doesn't work and it can't work, no matter how much dirty ethanol they test. They're putting the cart before the horse by trying to come up with reasons why it could work before proving that it does work. There are only two reasons I can imagine why they would do this:

1) They purposefully are trying to obscure the fact that it doesn't work;

2) They want the million dollars, so are trying to find ways to tell homeopathic solutions apart.

[pgwenthold]

Originally Posted by juryjone

They could take several different approaches to proving homeopathy:

3) Prove that some of the substance remains in the solution after properly controlled dilution, which flies in the face of Avogadro's limit and modern chemistry.

If material can be shown to remain in the solution after diluting to the point where the supposed concentration is below detectable limits, all that means is that they have not done the dilutions properly. Either they have not carried out the dilutions to the extent claimed, or that the solutions are not properly mixed before diluting again and they are sampling from a high concentration region.

The issue of concentration is not arguable. Either it has the concentration they claim or it doesn't. If they do a 30C dilution and there is more than 1 molecule per liter (or whatever their volume unit is), then that solution is not diluted to the level they have claimed.

[Rolfe]

Originally Posted by juryjone

They could take several different approaches to proving homeopathy:

1) Prove that a properly controlled homeopathic remedy cures the proscribed disease in a properly controlled double-blind experiment;

2) Prove that "like cures like", regardless of the potency of the remedy;

3) Prove that some of the substance remains in the solution after properly controlled dilution, which flies in the face of Avogadro's limit and modern chemistry.

Only one of these can be tested by the MDC, since Randi cannot do proper medical trials. And that is the approach taken here - proving that something detectable remains in the solution after all the dilution. It seems that they are positioning themselves to apply for the challenge - otherwise they'd just try to prove the stuff works, without regard to the chemistry behind it.

It doesn't work and it can't work, no matter how much dirty ethanol they test. They're putting the cart before the horse by trying to come up with reasons why it could work before proving that it does work. There are only two reasons I can imagine why they would do this:

1) They purposefully are trying to obscure the fact that it doesn't work;

2) They want the million dollars, so are trying to find ways to tell homeopathic solutions apart.

I suspect it's 3. They're convinced by all the subjective tales of miraculous cures, and believe it works. So they're trying to find a possible explanation.

Actually, all you need to do for the MDC is to be able to tell a potentised homoeopathic remedy (ultradilute) from the stock solvent. Which is what Roy is claiming to have done. You don't have to show what it is about the material that's allowing you to tell the difference. It dosn't have to be solute remnants, it could be a change in structure of the solvent. If indeed the remedies did have a different UV spectrum from the solvent, for whatever reason, then it would be a valid claim.

It's a weird claim, that the remedies have a lower absorbance than the solvent. I'd have trouble thinking up a reason for that, if it were the case. Fortunately, however, my brain doesn't have to do that work. Because real ethanol has a much much lower UV absorbance than whatever the heck he was testing. Presumably the remedies weren't as dirty as the solvent sample.

Nothing to see here, move along.

Rolfe.

[krazyKemist]

I've got the paper...

I particularly love this passage (my comments in brackets):

Quote:

We note that at very low signal levels, instrument noise coupled with artificial computer generated sensitivity can produce data that are not reliable [translation: data that do not suit us]. Hence we operate the instruments in the sensitivity ranges in which we sacrifice some precision for reproducibility.[translation: we thinker with the instruments until they give us noise we like, and we forego the computer treatment (generally addition of multiple spectra + fourier transform) that is aimed at eliminating noise]

the Kemist

[Wowbagger]

Assuming this portion is true

Quote:

Ultra-Violet–Visible (UV–VIS) spectroscopy illustrate the ability to distinguish two different homeopathic medicines (Nux vomica and Natrum muriaticum) from one another and to differentiate, within a given medicine, the 6c, 12c, and 30c potencies

(and it probably is not, but for argument sake, let us assume, temporarily, that it is)

You still have a problem of the body, itself, not only determining the difference, but determining what to do with the stuff once it does. I doubt that even if UV-VIS spectroscopy was sensitive enough to distinguish the difference, that our own body chemistry would also be able to do so.
(These are water molecules, we are talking about, after all.)

If homeopathy claims it is efficacious, it must pass proper medical trials, period.

[Pipirr]

Quote:

A Food and Drug Administration-regulated homeopathic pharmacy (Hahnemann Laboratories, San Rafel, CA) prepared samples of two different test solutions.

......diluted by the standard Hahnemannian techniques in 95% ethanol and succussed: a 30c potency is diluted (1/100)^30 or 10^60 from the original material.

They were hand-succussed by trained experts [http://www.hahnemannlabs.com/preparation.html] 30x20 = 600 times during the manufacturing process.

To answer a question about whether the samples were prepared in or out of the lab, the answer is out, by trained experts no less. And hand-succussed. Chicanery possible?

Succussing has extraordinary effects on 95% ethanol: Figure 3a shows a clear difference between succussed and unsuccussed ethanol (6, 12, 30C). That's without any additional compounds present. It looks like the ethanol trace in 3a was reused in 3b and 3c as the control, rather than being run anew with each batch of Nat mur or Nux vom samples.

Ok, anyone with access to a UV-spec, aliquot out some of your squeezy bottle 95% ethanol, bang it about and dilute in more 95% ethanol and get some before and after traces. This experiment looks cheap and repeatable.

Beats me why nobody has discovered this before.

[sts60]

The nanoheterogenous structure of water can be determined by interactive phenomena such as epitaxy (the transmission of structural information from the surface of one material to another without the transfer of any matter),

Um, no. I used to work in an epitaxy lab. In any meaningful sense, epitaxy is about the growth of solids materials, in particular crystalline thin-film structures. Liquid water does not have this kind of order. Is this guy really supposed to be a materials scientist?

Commenting on the special issue, Professor Chaplin said: “Science has a lot more to discover about such effects and how they might relate to homeopathy. It is unjustified to dismiss homeopathy, as some scientists do, just because we don’t have a full understanding of how it works.”

"It is unjustified to dismiss [ astrology | throwing people in the water to determine their guilt or innocence | foretelling via goat entrails | my lucky socks ] just because we don't have a full understanding of how it works."

"In his overview he is critical of the “unscientific rhetoric” of some scientists who reject the memory of water concept “with a narrow view of the subject and without any examination or appreciation of the full body of evidence.”

See, that's the problem, doc. They have looked at the full body of evidence. You're the one who wants to throw out physics and chemistry in favor of ever-fainter glimmers in the noise of instruments built by real scientists.

You've had two centuries to come up with something. Give it up.

[PixyMisa]

Just on Martin Chaplin - his name appeared in Roy's previous article, so I looked him up. He has a website with a ton of information on the structure of water, including several hundred bibliographical entries... Only one of which (that I could see) references an experimental study, and that one doesn't support his claims.

To call his work "entirely speculative" would be kind.

[JJM]

Originally Posted by krazyKemist

I've got the paper...
I particularly love this passage (my comments in brackets):

Quote:

{snip} Hence we operate the instruments in the sensitivity ranges in which we sacrifice some precision for reproducibility. [translation: we thinker with the instruments until they give us noise we like] {snip}

the Kemist

While I agree with your translation (i.e., I think that is what they did), Roy's statement is even more bizarre because precision is reproducibility.

[Dragon]

Originally Posted by sts60

...

See, that's the problem, doc. They have looked at the full body of evidence. You're the one who wants to throw out physics and chemistry in favor of ever-fainter glimmers in the noise of instruments built by real scientists.

You've had two centuries to come up with something. Give it up.

Echoes of Blondlot and Benveniste. Déjà vu all over again ...

[tracer]

Originally Posted by Pipirr

The defining role of structure (including epitaxy) in the plausibility of homeopathy

Manju Lata Rao, Rustum Roy, Iris R. Bell and Richard Hoover

... the fourth author's name is Dick Hoover?

[Badly Shaved Monkey]

Originally Posted by JJM

While I agree with your translation (i.e., I think that is what they did), Roy's statement is even more bizarre because precision is reproducibility.

I suspect he's forgotten that precision and accuracy are different things.

[geni]

No results from FTIR? FTIR data can be quite hard to fiddle.

[Pipirr]

Originally Posted by geni

No results from FTIR? FTIR data can be quite hard to fiddle.

They tried. They failed.

Quote:

The results show that such
materials can be easily distinguished from the pure
solvent, and from each other, by the use of UV–VIS
(ultraviolet–visual) and Raman spectroscopy, but
Fourier transformed infra red (FTIR) spectroscopy
proved insensitive to these differences.

And:

Quote:

FTIR Spectra (not shown
here) from all the samples of Nat mur and Nux vom
overlap neatly, clearly signifying that FTIR is not the
most sensitive technique for analyzing the subtle
structural differences in these types of samples.

[Rolfe]

Originally Posted by JJM

While I agree with your translation (i.e., I think that is what they did), Roy's statement is even more bizarre because precision is reproducibility.

Who do they get to scrutinise these manuscripts anyway? The window cleaner?

Rolfe.

[JJM]

Originally Posted by Rolfe

Who do they get to scrutinise these manuscripts anyway? The window cleaner?

Rolfe.

Actually, window-cleaning is a demanding job. They have to avoid leaving an annoying streak on your window, while not spending hours wiping one window.

By comparison, the homeopaths that "referee" these articles have it easy.

[Zep]

Forgive me, chemist-people and research scientists, but isn't spectrography based on the principle that there ARE specific molecules of test compound in existance that give the peaks in the readings? That is, regardless of the mix of compounds, ethanol always produces peak(s) at certain point(s) due to the fact that they ARE molecules of ethanol.

If so, wouldn't the results that the "homeopathic" ethanol lost its spectra peaks mean that there is no ethanol in that test mix at all? That means it is actually another compound altogether, or that it was a very shoddy test run.

The obvious conclusion I would come to is that Rustrum simply failed to maintain strict sterility and separation when he did the ethanol testing. IF he actually did the ethanol testing. So is that not a reasonable conclusion from the data?

Or have I missed something here...

[anor277]

Just to echo Rolfe's and Zep's comments, laboratory ethanol is a strange beastie. Absolute, pure alcohol, after rigorous drying, becomes 95% alcohol after exposure to air (it sucks up air-borne moisture). Because of statutory controls on the supply of "drinkable" alcohol, it is rare to use this in the lab.

What is generally used in the lab is IMS, industrial methylated spirits, that is regular ethanol that has been "denatured" by the addition of benzene, phenol, methanol, and other things, so that if you drink it, it would send you blind.

All of the aromatic denaturants, (benzene and the phenol) have significant absorptions in the UV, and this could be the signal that Rolfe claims is not characteristic of ethanol. At any rate different batches of IMS have different quantities of denaturant. Years ago, my old profs used to add water and lemon cordial to IMS that had not been significantly methylated (i.e. "denatured") for an instant party.

I don't know of course what solvent Roy used; anyone can make a mistake, but I would like a clear description of his source of ethanol and how he treated it.

[Pipirr]

Originally Posted by anor277

I don't know of course what solvent Roy used; anyone can make a mistake, but I would like a clear description of his source of ethanol and how he treated it.

No clear description given in the paper (see post 20). Presumably, and that's a big presumption, all the ethanol was handled and provided by Hahnemann Laboratories. In fact all that is stated is that the lab prepared Nux vom and Nat mur samples for them, and then sent them by overnight courier. There's no mention that they also sent in a blank sample of the same ethanol used in the succussions.

Did Roy's group use their own ethanol as a control, and not one provided by Hahnemann Lab's?

[Mojo]

Originally Posted by Zep

Forgive me, chemist-people and research scientists, but isn't spectrography based on the principle that there ARE specific molecules of test compound in existance that give the peaks in the readings? That is, regardless of the mix of compounds, ethanol always produces peak(s) at certain point(s) due to the fact that they ARE molecules of ethanol.

If so, wouldn't the results that the "homeopathic" ethanol lost its spectra peaks mean that there is no ethanol in that test mix at all? That means it is actually another compound altogether, or that it was a very shoddy test run.

The obvious conclusion I would come to is that Rustrum simply failed to maintain strict sterility and separation when he did the ethanol testing. IF he actually did the ethanol testing. So is that not a reasonable conclusion from the data?

I assume the claim is that the spectra are different because the structure of the ethanol has been subtly altered in some way (perhaps by changes in the hydrogen bonding between molecules making bonds more or less polar?). The other explanations you mention are at least as plausible.

[anor277]

Originally Posted by Pipirr

No clear description given in the paper (see post 20). Presumably, and that's a big presumption, all the ethanol was handled and provided by Hahnemann Laboratories. In fact all that is stated is that the lab prepared Nux vom and Nat mur samples for them, and then sent them by overnight courier. There's no mention that they also sent in a blank sample of the same ethanol used in the succussions.

Did Roy's group use their own ethanol as a control, and not one provided by Hahnemann Lab's?

I've yet to read the paper, but as you say, a control sample of ethyl alcohol would be key. I don't know what nux vom is either (something to avoid); regarding nat mur, it is a fact that sodium chloride has next to no solubility in 95% ethyl alcohol (it is a standard undergraduate expt to prepare solutions of sodium chloride, bromide, iodide, and then add a squirt of alcohol - and out come the crystals of what?). So what is the actual procedure in making nat mur in ethyl alcohol? The likelihood of contamination by something is very high.

[shpalman]

Originally Posted by Mojo

I see Milgrom is still talking about "macro-entanglement" as if it's an actual mechanism rather than a metaphor.

At least he gets the units of Planck's constant right this time, even if he still can't spell the names of Del Giudice, Gribbin or Auyang.

The article by Teixeira explains clearly why it's all a pair of dingo's kidneys anyway.

[shpalman]

Originally Posted by anor277

I don't know what nux vom is either (something to avoid)

It's the tree from which we get noted rat poison and murder weapon strychnine.

[Mojo]

Originally Posted by anor277

...it is a fact that sodium chloride has next to no solubility in 95% ethyl alcohol...

A member of the chemistry department at my uni was reckoned to be the world's leading authority on the behaviour of ionic solutes in non-polar solvents...

[Baron Samedi]

I'm looking at the PDF/PPT file, and I have a question. Does anyone know why the graphs on slide 31 show nux vom in descending order (6c highest, then 12c, then 30c), yet on page 30 the nat mur sample goes from 12c to 30c to 6c? Did Roy try to explain that in the non-powerpoint paper?

[Rolfe]

Originally Posted by Mojo

I assume the claim is that the spectra are different because the structure of the ethanol has been subtly altered in some way (perhaps by changes in the hydrogen bonding between molecules making bonds more or less polar?). The other explanations you mention are at least as plausible.

As far as I can make out, there is no claim at all. He just presents the spectra and notes that they are different. Why they might be different seems not to have entered anyone's head.

Having said that, I'm going by the slide show, not the paper. I'll have a look at the paper at lunchtime.

The point about ethanol as a solvent for UV spectroscopy is that it doesn't absorb significantly above about 280nm. If you start using some preparation with additives that do absorb above 280nm, you've rather destroyed the point of the whole thing. Which doesn't mean that isn't exactly what has happened.

Rolfe.