canada forms ch.e. society
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effort but also wanted to obtain a system that provides increased amounts of statistical data on various aspects of product uniformity, Dr. Rehm says. For the past two years, Ciba and Aminco have developed the instrument to provide the versatility Ciba requires while retaining design adaptability to accommodate other drug companies' possible interests.
The Assayomat can be programed to dispense a tablet, add solvent, soni-cally dissolve the tablet, filter the solution, dilute it to a preselected concentration, and measure ultraviolet ab-sorbance. With this sequence, the instrument can assay up to 400 tablets at a maximum rate of 120 assays per hour. It can perform different analyses on as many as 20 different types of tablets. And since pharmaceutical production is generally done in batches of various products at the same time, this versatility has been designed into the system. A program card corresponding to each different procedure directs the instrument to follow the appropriate analytical program in a continuous, hands-off operation.
Dr. Rehm estimates that about 80% of Ciba's 72 tableted products are amenable to programed analysis. In each of these cases, the active ingredient being assayed shows desirable solubilities and concentration sensitivities to UV absorbance. Common to the analyses of these tablets are only four variables: type of solvent; sonifying time for dissolution; concentration; and UV wave length. The instrument accommodates these variables and can thus be programed to carry out 20 different procedures.
The tablet dispenser is a vertical stack of 20 circular trays, each of whose 20 tablets is assayed by the procedure of the corresponding program card. A preselected solvent in any one of five quantities is added to a dispensed tablet. A sonic transducer operating at 10,000 c.p.s. is lowered over the tablet, dissolving it in less than a minute.
The solution is then filtered and transferred to a container or a conveyer belt for dilution. The diluent burets dispense one of three solvents in any one of five quantities. The solution is then drawn into a flow-through cell in the spectrophotometer for analysis. As one sample is being recorded, another is being diluted, and a third is being sonified, thus maximizing the Assayomat's output.
An electronic programing system controls the electrical and mechanical operations of the Assayomat. Control is a closed-loop system with stepping switches programing sequence control and instrument variables.
Ciba expects to spend several months incorporating the Assayomat
into its quality-control operation. Standard absorbance readings must be made on all the pure drugs while determining the most suitable solvents, concentrations, and wave lengths for each assay procedure. Furthermore, the results of the instrument will be correlated with those from standard laboratory methods to establish confidence and reliability in the instrument.
Nobel Prize to Rous, Huggins Dr. Francis Peyton Rous, the first man to discover a cancer virus, and Dr. Charles B. Huggins, the first to control a major type of cancer with chemicals, will share the 1966 Nobel Prize in Medicine. Dr. Rous, 87, pathologist at Rockefeller University in New York City, and Dr. Huggins, 65, University of Chicago professor of surgery, will each receive a gold medal and $30,-000.
This recognition has been a long time coming for the two veteran U.S. medical research scientists—especially for Dr. Rous. He is being cited for his 1910 discovery of a virus that invokes malignant tumors in hens. Dr. Huggins' selection for the prize is based on discoveries, dating back to the 1930's, concerning the use of hormones to treat prostate and other cancers.
The medical faculty of Sweden's Royal Caroline Institute, which awards the medicine prize, points out that the significance of Dr. Rous' discovery has increased every year since the isolation of a leukemia virus in mice in 1951. The importance of the Rockefeller scientist's work has only been comprehended in the last decade. Discovery that the Rous virus can evoke tumors in many animals has started a trend in favor of the virus theory of cancer, which has long been neglected.
Dr. Huggins' work in cancer therapy was triggered by his discovery, while doing experiments on dogs, that functioning of the prostate gland depends on production of androgens. This led to the discovery that female sex hormones can control cancer of the prostate.
Dr. Rous received his M.D. from Johns Hopkins in 1905. He spent the next year in residence at the same school. After two years as instructor in pathology at the University of Michigan, he moved to Rockefeller.
Dr. Huggins received his M.D. from Harvard University in 1924 and interned at the University of Michigan for the next two years. He then became one of the original faculty of the University of Chicago medical school. In 1951 he also became head of the university's Ben May laboratory for cancer research.
Dr. Charles B. Huggins Cancer control
Dr. Francis Peyton Rous Cancer cause
Canada forms Ch.E. society Chemical engineering has a new voice in Canada. It was heard for the first time last week in Windsor, Ont., where the 16th Canadian Chemical Engineering Conference took place under sponsorship of the newly formed Canadian Society for Chemical Engineering.
Previously, the conference had been sponsored by the Chemical Institute of Canada, the new society's parent. CIC, at its annual conference (held in Saskatoon in July), announced ratification of bylaw changes making the new chemical engineering society possible. From CIC's formation in 1945 until now, chemical engineering had been a division of the institute, becoming in later years its largest.
CSChE will operate as a constituent
OCT. 24, 1966 C&EN 23
society of CIC. As such, it will be financed from the resources of the institute and will represent the institute in chemical engineering, both nationally and internationally.
There had been some sentiment in Canada for a completely separate chemical engineering organization. However, a committee formed by the chemical engineering division of CIC to study the position of the chemical engineer within the institute determined that it was both economically and professionally desirable for chemical engineering to remain a part of CIC.
The society's first group of elected officers, announced last week in Windsor's crowded Prince Edward Hotel, will be headed by the new president, Dr. William H. Gauvin, research manager of Noranda Research Centre, Pointe Claire, Ont. Vice president is Dr. R. H. Clark, head of the chemical engineering department at Queen's University, Kingston, Ont. CSChE's first officers were those of the former CIC Chemical Engineering Division. Dr. D. E. Robinson, chairman of the department of chemical and petroleum engineering at the University of Alberta, was the first president. Dr. Gauvin had been vice president.
The new officers had a growing organization of some 2500 members— about a third of CIC's 8000 members. For its inaugural conference last week, the society put together a three-day program of 18 sessions that included more than 80 papers.
Under CIC's new bylaws, other CIC divisions or groups of distinctive academic disciplines can apply to form constituent societies if they desire. CIC now has nine divisions representing different areas of chemistry.
GE chemists make new silane Chemists at General Electric say they have synthesized the first known optically active silane with two oxygen atoms attached to the silicon. Dr. Johann Klebe and Dr. Herman Fink-beiner, of GE's general chemistry laboratory, Schenectady, N.Y., prepared naphthoxymethoxymethylphen-ylsilane by reacting stepwise a new ring structure—silaoxazolidone, which contains an optically active silicon atom—with 1-naphthol and methanol [/. Am. Chem. Soc, 88, 4740 (1966)] . Previously, preparation of optically active silanes has been limited to compounds having at most one silicon-oxygen bond.
In preparing the new ring structure, the GE chemists reacted bis ( N-methyl-acetamido ) methylphenylsilane with optically active N-phenylalanine in benzene at room temperature. Dr. Klebe and Dr. Finkbeiner used an N-phenyl amino acid because it "cleanly and smoothly" produces the desired ring structure.
Since the product, 2-(methylphenyl-sila) - 3-phenyl-4-methyloxazolidone-5, contains two asymmetric centers, diastereomers are produced. Normally, in a reaction such as this, the diastereomers must be separated physically or chemically if an optically pure system is desired. In the GE work, one of the diastereomers is less stable and rearranges to the more stable isomer. This eliminates the necessity of separating two very similar materials from each other.
The nuclear magnetic resonance spectrum of the cyclic product shows two separated silicon-methyl peaks and two carbon-methyl doublets. When the solvent and acetamide are
removed, the liquid mixture spontaneously converts to the predominant diastereomer. In solution, an equilibrium mixture of the two diastereomers is slowly attained.
To prepare the linear, optically active difunctional silane, Dr. Klebe and Dr. Finkbeiner reacted equivalent amounts of 1-naphthol and silaoxaxoli-done in the first step at room temperature. The reaction is fast and NMR shows it gives essentially optically pure products.
However, the naphthoxysilyl ester produced in this reaction racemizes spontaneously with a half-life of a few hours. Any subsequent reaction aimed at separating the amino acid from the silicon portion of the molecule must not only be stereospecific, but fast enough to minimize racemiza-tion, the GE chemists say. They found methanol to be a suitable reagent which leads to the formation of naphthoxymethoxymethylphenylsi-lane, which has a specific rotation of +21.9°.
Educacion Quimica debuts The first issue of Revista Iberoameri-carta de Educacion Quimica, a Spanish language chemical journal for high school students, has been published. The National Science Foundation and the Agency for International Development provided funds to start the journal. The American Chemical Society is initially administrating the project through a Latin American board. The journal is being printed through the cooperation of the Sociedad Quimica de Mexico.
Dedicated to the problems of chemical education, the journal is designed to transmit new concepts and ideas from research and university scientists to high school students and teachers, as do the Journal of Chemical Education and Chemistry in the U.S.
The independent journal, a quarterly, is starting with translations from Chemistry, Journal of Chemical Education, C&EN, and other publications. To remain international in character and become a communications medium among professionals of Iberoa-merica, the journal requests original material, based on scientific activities and pedagogical experience.
The editorial director of Educacion Quimica is Prof. Jose Gomez-Ibanez of Wesleyan University, who is supported by a Latin American board of chemists from Mexico, Chile, Argentina, and Brazil.
Subscriptions to the new publication should be sent to the Sociedad Quimica de Mexico (c /o Administra-cion de Correos No. 4, Mexico, D.F. ) . The cost is $2.00 a year.
24 C&EN OCT. 24, 1966
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