Reliable. Fast and Easy. MCI automatic analyzer. Utilizes A S V m e t h o d to s i m u l t a n e o u s l y m e a s u r e c o n c e n t r a t i o n s of 5 different trace h e a v y m e t a l s . Ultra-high sensitivity a n d a u t o m a t i c s a m p l e feed/discharge m e a s u r i n g cell a s s u r e s fast, precise r e s u l t s . R e p r o d u c i b i l i t y is 3-to-20%. Range: 0.1 PPB—10 P P M .
with a small window through which we now can observe some of t h e pro cesses t h a t take place in red blood cells.
Acknowledgment It is a pleasure to acknowledge nu merous discussions about t h e tech niques described in this article with T o m Nakashima and Glen Bigam. Some of t h e red blood cell work was done while on sabbatical leave at Ox ford, and received considerable stimu lation from a lecture given by R.J.P. Williams at a meeting of t h e Chemical Society. T h e spectra in Figures 6-8 were provided by Nicolet Technology Corp., Mountain View, Calif. 94041.
References (1) T. C. Farrar and E. D. Becker, "Pulse and Fourier Transform NMR", Academ ic Press, New York, N.Y., 1971. (2) D. Shaw, "Fourier Transform NMR Spectroscopy", Elsevier, New York, N.Y., 1976. · (3) E. L. Hahn, Phys. Reu., 80, 580 (1950). (4) R. Freeman and H.D.W. Hill, in "Dy namic Nuclear Magnetic Resonance Spectroscopy", L. M. Jackman and F. A. Cotton, Ed., ρ 131, Academic Press, New York, N.Y., 1975. AS-01 Trace Metal Analyzer (5) I. D. Campbell, C. M. Dobson, R.J.P. Williams, and P. E. Wright, FEBS Lett., 57,96(1975). (6) D. Shaw, "Fourier Transform NMR MITSUBISHI CHEMICAL INDUSTRIES LIMITED Spectroscopy", ρ 196, Elsevier, New Instruments Dept., Mitsubishi Bldg., 5-2, Marunouchi 2-chome, Chiyoda-ku, York, N.Y., 1976. Tokyo, 100 Japan Telex: J 2 4 9 0 1 Cable Address: KASEICO TOKYO (7) F. F. Brown, I. D. Campbell, P. W. Kuchel, and D. L. Rabenstein, FEBS Lett., CIRCLE 136 O N READER SERVICE CARD 82,12 (1977). (8) A. DeMarco and K. Wuthrich, J. Magn. Reson., 24, 201 (1976). (9) I. D. Campbell, C. M. Dobson, R.J.P. Williams, and A. V. Xavier, ibid., 11,172 (1973). (10) M. Gassner, O. Jardetzky, and W. Conover, ibid., 30,141 (1978). (11) C.H.A. Seiter, G. W. Feigenson, S. I. Chan, and M.-C. Hsu, J. Am. Chem. Soc, 94, 2535 (1972). (12) S. L. Pratt and B. D. Sykes, J. Chem. Phys., 56, 3182 (1972). (13) G. Bodenhausen, R. Freeman, R. Niedermeyer, and D. L. Turner, J. Magn. Reson., 26,133 (1977). (14) W. P. Aue, E. Bartholdi, and R. R. Ernst, J. Chem. Phys., 64, 2229 (1976). (15) L. Muller, A. Kumar, and R. R. Ernst, J. Magn. Reson., 25, 383 (1977V
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Dallas L. Rabenstein is an associate professor of chemistry at the Univer sity of Alberta. His research interests include nuclear magnetic resonance spectroscopy, clinical applications of liquid chromatography, coordination chemistry, and the chemistry of heavy metal toxicology.