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Dispelling the 'Law of Wiechers' and Maximizing Actives Delivery
By: Johann W. Wiechers, PhD, JW Solutions
Posted: December 16, 2010
Perhaps the highest level of arrogance a cosmetic scientist can display is to name a law after himself. However, this law was not named by me, it was named by my friend and colleague Jonathan Hadgraft, PhD, emeritus professor of biophysical chemistry for the department of pharmaceutics at the University of London's School of Pharmacy. This column was written on Dec. 16, 2010, on Hadgraft's 60th birthday; therefore, this column is in honor of him.
Hadgraft and his friend Richard H. Guy, PhD, professor of pharmaceutical sciences at the University of Bath's department of pharmacy and pharmacology, were the “enfants terribles” of the skin delivery field. At every conference that discussed skin delivery, the two arrived with something novel, and each time they were right about what they stated. These two gentleman peeled away the secrets of skin delivery like the rings of an onion, but without a tear. The two revolutionized the skin delivery of topically applied drugs.
My first memories of Hadgraft (and Guy) go back to 1987 at the second American Association of Pharmaceutical Scientists (AAPS) Congress in Boston. I was presenting my first scientific poster on the percutaneous absorption of azone, a skin penetration enhancer. As a young doctorate student, I was lucky that azone was such a promising skin penetration enhancer. It always guaranteed visitors at my poster, which resulted in a constant crowd.
Upon return from lunch one afternoon, there were two men debating in front of my poster. I asked what the debate was about and if I could assist in resolving the obvious dispute. At this moment, their name tags revealed them as the young but famous professors: Hadgraft from Cardiff University and Guy of the University of California. I felt stupid offering two of the most famous men in skin delivery my advice but they included me into their discussion as if nothing had happened. By now I have forgotten what the discussion was all about, in the same way that back then I forgot to ask for their autographs.
We’ve continued to meet over the years and in 2007, Hadgraft offered me a visiting professorship at the University of London's School of Pharmacy, where he moved to from Cardiff via Greenwich University in 2004. During one of my recent presentations there on formulating for efficacy, he advised the students not to forget the "Law of Wiechers in Cosmetics." In response, my expression shifted to looking just as puzzled as all the students, and as clueless as you may look right now.