CHEMICALS
NEW
CHEMICALS
REAGENTS MATERIALS
Lot-Analyzed Solvents Three more high-purity solvents are added to the list of Certified Grade reagents available from Fisher Scientific Co. They are ethylene dichloride, designated E-175; ethylene glycol monomethyl ether, E-182; and triethanolamine, T-407. Ethylene dichloride is described as a base for many organic syntheses, having important uses in concentrating vitamins A and D from liver oils, and in vapor phase degreasing of electronic components. Ethylene glycol monomethyl ether is said to have many analytical uses, especially in colorimetric determination of both cations and anions. Triethanolamine is used as a solvent for cellulose acetate and as a chromatographic solvent. It is a mildly alkaline buffer. The company says that the T-407 product contains a maximum of 1.8% mono- and diethanolamines, compared with up to 15% in the TJSP grade. C-l Rare Earth Metals Six high purity rare earth metals— dysprosium, erbium, gadolinium, holmium, samarium, and ytterbium—are added to the products line available from High Purity Metals, Inc. The materials, which may be obtained in minimum 25-gm. lots, are refined to the following purity levels, according to the company: iron, less than 0.03% ; tantalum, less than 0.01%; other rare earths, less than 0.1%; oxygen, less than 0.1?r ; and silicon, calcium, etc., traces only. C-2
test method which enables analysis of monoglyceride at levels as low as 0.05%. The products are available in 5-, 30-, and 50-gram ampules, sealed under inert gas. C-3
the categories, 7-bottle kits of the more frequently used reagents come in rubber-coated wire carrying racks. C-4 Tracer Compound
Reagents and Dye Solutions More than 50 standardized Volutec reagents and dye solutions for paper chromatography and electrophoresis are available from Research Specialties Co. in 200-ml. aerosol spray bottles. A plastic coating on the bottles prevents breakage and shields the contents from the effects of light. The tight seal for retaining the aerosol also protects the contents from contamination. The reagents available are useful for studying the following classes of organic substances: aliphatic acids and amines, amino acids, carbohydrates, lipids, phenols, proteins, purines, pyridine nucleotides, pyrimidine reduction products, steroids, and vitamins. For several of
Thymidine-methyl-H 3 , a new compound being offered by New England Nuclear Corp., is a precursor of both RNA and DNA and can be used for studies of cell growth, genetic patterns, turnover, and others. The specific activity currently supplied is 2360 millicuries per millimole but greater specific activities are available on request. The company says that independent laboratories have confirmed the compound's biological activity and that chromatographic analysis has shown it to be radiologically pure. License exempt packages of 250 microcuries are priced at $15. One millicurie and five millicuries are $40 and $160, respectively. C-5
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Ultrapure Triglycerides Three ultrapure triglycerides—trioleate, tristearate, and trilinoleate—are now offered by The C. P. Hall Co. of Illinois. The company says that extremely pure triglycerides are rare in nature and almost as rare in synthetic form. Even when the product is prepared from the pure acid, as by interesterification between the pure methyl ester and glycerine, it contains monoand diglycerides and their positional isomers. These are difficult to remove by conventional methods. Also, in order to test for the impurities, the company cooperated with the University of Wisconsin's pharmacy department in developing a chromatographic
i/6 Aperture Littrow Type Optical System Direct Reading in Millimicrons 200 to 700 Millimicrons Wavelength Range Entrance and Exit Slits Adjustable in Unison Optics of UV Grade Fused Silica Motor Driven Wavlength Movement Plus a Fine Adjustment for Individual Settings. FOR FURTHER DETAILS,
PLEASE WRITE
TO:
O. C. RUDOLPH & SONS, INC. P. O. BOX 446, CALDWELL, NEW JERSEY Circle No. 9 on Readers' Service Card
VOL. 3 3 , N O . 4 , APRIL 1 9 6 1
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