NEW
CHEMICALS REAGENTS
CHEMICALS
MATERIALS Lipid Distribution Sponsored by National Institutes of Health Through a cooperative project of NIH's Division of Research Grants and National Heart Institute, ampoules containing 200 mg. of mixtures of pure fatty acid methyl esters will soon be available for distribution to qualified investigators who need such materials in their research. The samples should be useful in calibrating and standardizing analytical techniques requiring only small amounts of lipids. Additional literature will be available to assist those wishing to apply the materials in gas liquid chromatography. Persons desiring the samples should describe briefly the purposes for which they will be used. The advisory committee for the program will attempt to fill all deserving requests, but the aim is also to assure broad distribution to areas where needed. Letters should be addressed in duplicate to Dr. W. H. Goldwater, executive secretary, Metabolism Study Section, Division of Research Grants, National Institutes of Health, Bethesda 14, Md. Biochemicals and Radiochemicals Offered New offerings announced by Schwarz BioResearch, Inc. include three halogenated deoxynucleosides, five 5'-ribonucleoside di- and triphosphates, and three radioactive compounds. Bromodeoxycytidine, bromodeoxyuridine, and iododeoxyuridine all come in crystalline form. These are said to be of special interest as antimetabolites in DNA synthesis. The substituted deoxynucleosides may also be useful in studies of radiosensitivity of cells. Also offered by the company are cytidine 5'-diphosphate, dilithium; cytidine 5'-triphosphate, sodium; uridine 5'-diphosphate, crystalline lithium; uridine 5'-diphosphate glucose, sodium; and uridine 5'-triphosphate, lithium. These five materials are said to be chromatographically homogeneous. The three new radioactive compounds are optically pure tritiated L-proline (spec, act: 1.0 curie/millimole), tritiated L-tyrosine (0.35 curies/millimole), and tritiated L-histidine (1.7 curies/millimole). C-l Chromatography Solid Support A new solid support for chromatography introduced by The Fluorocarbon
Co. is said to be particularly effective in reducing tailing caused by adsorption of highly polar components by active sites on support material. Known as Fluoropak 80, it is claimed to be especially useful in analyzing ammonia, amines, water, and highly corrosive substances. The company says that a special processing technique is used to reduce flocculating characteristics of the basic material. This makes coatings up to 10% by weight possible and enables packing of columns up to 30 feet in length. The support is available in half-pound and one-pound packages at laboratory supply houses. C-2 Chromatography Column Packings A selected series of column packings for gas chromatography is offered by Lachat Chemicals, Inc. The company points out that a comparatively few types of liquid phases can be used to analyze almost all high molecular weight
aliphatic chemicals; and it adds that the series now offered was chosen to do a serviceable and competent job. The substances are diethylene glycol succinate polyester, diethylene glycol adipate polyester-phosphoric acid, carbowax-alkaline, Apiezon L, neopentyl glycol succinate 3% coating, and SE-30 silicone gum rubber 2% coating. All are available at $25 for 25 grams, $40 for 50 grams, and $60 for 100 grams. Prices on larger amounts are supplied on request. C-3 Dimethyl Popop A new scintillator, dimethyl Popop has been introduced by Arapahoe Chemicals, Inc. The compound is said to be a band-shifter or secondary solute with properties superior to Popop in many ways. The company says that this is especially true in that it has a higher fluorescence maximum and greater solubility. C-4
YOU'VE GOT IT IN 30 SECONDS! Brookfield Synchro-Lectric Viscometers Accurately Measure Viscosity of Any Fluid With the new 8-speed Brookfield Viscometer just attach the spindle, level, and immerse the unit in the test material, then depress the clutch and flip the motor switch. Within 30 seconds, above 4 RPM, you'll have an accurate reading in centipoises on the simple dial. Anyone can do it, without special training. Easy to clean? Just rinse and wipe the spindle! Versatile? Use it for measuring any fluid at any temperature! Complete information is yours in our new catalog. Why not write for your copy today? World's Standard for Viscosity Measurement and Control
Brookfield ENGINEERING
LABORATORIES,
INC.
STOUGHTON 212, MASSACHUSETTS
Circle No. 30 on Readers' Service Card VOL.
33,
NO.
9,
AUGUST
1961
·
115
A
