Editors' Column Analytical Chemistry and Medicine The recent publication of a study, "Chemistry in Medicine", by the American Chemical Society outlines the contributions of chemists in pro viding improved products and proce dures for health care. The report, pub lished by the Committee on Chemistry and Public Affairs, reviews past ac complishments, discusses the current state of knowledge, and suggests fu ture potentials of chemistry in medical research. In one section on the contri butions of basic research, "Chemistry in Medicine" discusses the value of
Copies of "Chemistry in Medicine" are available at $7.50 each from Special Issues Sales, American Chemical Society, 1155 16th St., N.W., Washington, D.C. 20036.
developments in analytical chemistry. Increased sensitivity of analyses and sophisticated instrumentation now allow for the measurement of a chemi cal's presence or behavior in a com plex system to a degree not possible before. Basic analytical methodology plays an important role in chemistry's con tributions to medical research. Contri butions related to the development of drugs are some of the most widely known. Drugs available today radical ly alter the capabilities for treating ill nesses. Most drugs are transformed in the body. The reactions involved must be studied to understand drug metabolism and to aid in the discovery of new drugs. Here very sensitive (parts-per-million) separation and de tection techniques identify these reac tion sequences and their importance. Many of the sensitive methods and instruments widely used in pharma
ceutical as well as other areas of medi cal research were originally developed for use in other fields. Mass spectrom etry, for example, can detect minute quantities of drugs and their metabo lites. Structures can be deduced from mass spectra by studying the ion frag ments. Radioisotope techniques also provide highly sensitive and practical methods for quantitative drug metab olism studies. In medical research, different forms of chromatography are used to sepa rate small amounts of both natural and synthetic chemicals. Chromatog raphy is important in the study of dis eases caused by inborn errors of me tabolism. In addition, the combination of gas chromatography with mass spectrometry produces a powerful tool for separating and identifying chemi cals important in disease studies. Other forms of spectrometry, especial ly infrared and ultraviolet, are used in the study of steroid chemistry. Flu orescence spectrometry detects ele ments present in living tissues. Laser probe technology and x-ray emission spectrometry are two analytical tech niques that also show promise in med ical science. These techniques will allow the detection of trace elements in very small sample sizes, such as a single drop of blood.
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384 A · ANALYTICAL CHEMISTRY, VOL. 50, NO. 3, MARCH 1978
Many of these basic analytical methods also contribute to diagnostic testing. In the clinical laboratory many analyses are now run routinely and automatically on blood and tissue samples; the determination of cholesterol and fats, the determination of various ions such as sodium and potassium, and enzyme analyses are a few examples. T h e analytical methods involved must be refined to the point where accurate tests can be run continuously and automatically by relatively unskilled technicians. As noted in "Chemistry in Medicine", perhaps one of the greatest analytical needs today is for methods t h a t will permit biological processes to be studied in detail at the molecular and atomic levels. Detecting small changes in concentration and determining how molecules are functioning inside cells will assist in providing basic information about cell processes. A first move in this direction is ion-selective membrane electrodes. These electrodes are m a d e small enough to permit direct m e a s u r e m e n t in the body. M e m b r a n e s modified with a layer of an appropriate enzyme are used to measure body fluid constituents such as glucose, urea, and phenylalanine. Much research is needed to try and match body chemical reactions with ionic measurements and to expand the n u m b e r of different ions t h a t can be measured. Research in this area will lead to a better understanding of many body processes including nerve conduction, muscle contraction, bone formation, and blood coagulation. Dr. T h o m a s P . Carney, president of Meta tech Corp., headed the fourm a n subcommittee responsible for "Chemistry in Medicine". In the preface, Dr. Carney states: " F u t u r e historians may well view the late 1960's and early 1970's as one of those inflection points when major scientific findings raised health care to a new, higher levelTThe prospects offered by increasing knowledge of cellular function at the molecular level clearly presage impelling scientific gains. So does the growth in sophisticated analyses, instruments, and diagnostic techniques. We are thus in a period of great scientific promise." Developments in analytical methodology are clearly playing a very import a n t role in medical research. As shown in this brief overview, analytical chemists are contributing to the search for new drugs and diagnostic tools. These will aid the physician in treating and preventing many illnesses. In addition, the growth of sophisticated analyses and instruments will provide a better understanding of diseases and complex body processes. Deborah C. Stewart
"Thankswill study with care." Dr. William F. Drea Research Laboratory Colorado Springs, Colorado
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ANALYTICAL CHEMISTRY, VOL. 50, NO. 3, MARCH 1978 · 385 A
