McConnell, Harden

Prof. Harden McConnell Ph.D., Professor of Chemistry, Stanford University, Stanford, California... 

Alan MacDiarmid (1927-2007) once said "Chemistry is about people" In this spirit, full names and birth and death dates are given to all the scientists quoted in this book such brief historical data may help illuminate how and when science was done. I have resisted mentioning who was a Nobel prize winner too many to list, and some worthy scientists—for example, Mendeleyeff, Eyring, Edison, Slater, and Tesla—were not honored. I owe a deep debt of gratitude to many people who have educated me over several decades, as live teachers and silent authors. In particular, I am indebted to Professor Willard Frank Libby (1908-1980), who taught us undergraduates at UCLA to love current research problems and led us into quite a few wild-goose chases Professor Harden Marsden McConnell (1927- ), who led us at Caltech and Stanford by example to see what are... 

However, metallic conduction in organic systems had been dreamt of as early as 1911 [1]. Until the mid 1960s the serious researchers of the organic solid state were few Hideo Akamatsu [2], Noel S. Bayliss [3], Melvin Calvin [4], Daniel D. Eley [5], Helmuth Kainer [6], Aleksandr I. Kitaigorodskii [7], Jan Kommandeur [8], Yoshio Matsunaga [9], Harden M. McConnell [10], Albert Szentgyorgyi [11], A.N. Terenin [12] and A.T. Vartanyan [12]. 

At Stanford, Harden M. McConnell developed a new technique, called spin labelling, based upon EPR spectroscopy. While carbon-centered free radicals are extremely reactive and short-lived, radical oxides of nitrogen, such as NO and NO2, are moderately stable. McConnell noted that nitroxyl radicals (RR N-O) are extremely stable if R and R are tertiary and can be chemically attached to biological molecules of interest. In 1965, he published the concept of spin labeling and, in 1966, demonstrated that a spin-labelled substrate added to a-chymotrypsin forms a covalent enzyme-substrate complex. The EPR signal was quite broad suggesting restricted motion consistent with Koshland s induced-fit model. In 1971, McConnell published a smdy in which spin labelling indicated flip-flop motions of lipids in cell membranes. This was the start of dynamic smdies of cell membranes. 

George B. Sigal, Dean G. Hafeman, J. Wallace Farce, and Harden M. McConnell... 

Barton A. Smith and Harden M. McConnell, Determination of molecular motion in membranes using periodic pattern photobleaching, Proc. National Academy of Sciences, USA 75, pp 2759-2763, 1978. 

Robert M. Weis, Krishna Balakrishnan, Barton A. Smith, and Harden M. McConnell, Stimulation of Fluorescence in a Small Contact Region between Rat Basophil Leukemia Cells and Planar Lipid Membrane targets by Coherent Evanescent Radiation , /. Biological Chem., 257,1982, pp 6440-6445. 

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