Chemistry

The past couple of months have seen substantial media coverage concerning the work of South Korean biomedical scientist Dr Hwang Woosuk.

Dr Hwang claimed to have cloned human embryos and obtained stem cells from them, and two papers reporting these findings were published in 2004 and 2005 in the prestigious American journal Science. His work made him a national hero in South Korea and appeared to be an enormous advance in the field of biotechnology.

However, last month, investigators at Seoul National University concluded that the two papers were fabricated and Dr Hwang was stripped of his title as chair professor at the university. Also last month, Dr Jon Sudbo, a cancer researcher in Norway, was found to have fabricated a study into oral cancer, results of which were similarly published in a high-ranking journal, The Lancet.

Sadly, fraud does occur in science, but those of us in the chemistry profession would like to think that we are relatively immune to the temptations of making up results.

While it’s probably fair to say that the incidence of fraud in chemistry is less than that found in the biomedical sciences, there have been a few celebrated cases over the past couple of decades, and today’s column details one such instance.

In 1994, a paper titled “Enantioselective Reactions in a Static Magnetic Field” was published by authors from the University of Bonn in the German journal Angewandte Chemie, possibly the best general chemistry journal in the world.

The results reported in this paper were absolutely extraordinary, and if true, would have made the authors extremely rich and certainties for a Nobel Prize. The paper concerned enantiomers, a term used to describe two molecules that are identical in every respect except for the fact that they are distinguishable mirror images of each other; in other words, they are related to each other in the same way as our right and left hands — mirror images, but obviously different.

While this may seem a trivial distinction, it is, in fact, incredibly important, especially in nature. While not every molecule has an enantiomer, biologically important molecules such as amino acids and sugars can potentially exist as two enantiomers, although they are generally found only as a single enantiomer in natural systems. Likewise, many synthetic drugs must be prepared as a single enantiomer, as the other enantiomer is often inactive or can indeed be dangerous — thalidomide is the best-known example of this.

Normal chemical synthesis of molecules usually results in the formation of both possible enantiomers in equal quantities, and the separation of these enantiomers is usually a time-consuming, wasteful and costly business.

Thus, chemists have, for many years, attempted to develop “enantioselective” reactions, which yield only one of two possible enantiomers. While there have been many notable successes in this area, such reactions often require exotic and very expensive reagents.

So the 1994 claim that reactions could be made enantioselective simply by carrying them out in a strong magnetic field met with enormous interest around the world, and many laboratories set about replicating the results.

Alas, it soon became obvious that the German group’s experiments simply could not be repeated and it transpired that the lead author on the paper, one Guido Zadel, had fraudulently manipulated the data. The paper was retracted by the other authors and Mr Zadel was stripped of his doctorate by the University of Bonn in 1996. However, he then took the university to court in an effort to get his doctorate reinstated and it was not until 2004 that the legal proceedings finally ended, with the court finding for the university.

So what is the moral of the story? It is, I suppose, that scientists can and do commit fraud. But one of the beauties of science is that fraud can easily be detected, especially in cases such as this, where a huge breakthrough is claimed. Reproducibility is a cornerstone of science and if reported results cannot be reproduced by others, the results are not real. Mr Zadel never had a hope of getting away with his deception and it was always only a matter of time before he got caught. I wonder what the former Dr Zadel is doing now.