NEW CHEMICALS
Le Column Packing
Durapack-Carbowax 400/Corasil is a new packing which offers the combined advantages of a permanent, chemically bonded liquid phase and a porous silica layer on a solid glass core. I t is suitable for difficult liquid chromatography sep arations such as isomeric mixtures and polar compounds including oxygenated, halogenated, and nitrogen derivatives. The material is available in 25-cc units, with particle sizes ranging from 35 to 50 microns. Price per unit is 395. Waters Assoc, Inc. 215-735-2400 501 Serum Cholesterol Determination
A kit for the precise colorimetric de termination of serum cholesterol, CholeTech, contains a complete set of pre tested reagents and standards (100 to 200 mg% cholesterol in glacial acetic acid). It includes reagents for the cor rection of icterus, detailed procedure, and % Τ conversion chart. Uni-Tech. 201-859-2151 502
Ecology Technology with...
...LDC MERCURY MONITORING
Features: •
Highest mercury sensitivity — .005 μg full scale; minimum detectable .0001 /ig/ml (one part per trillion in 50 ml H2O sample) • Fast — 15 second response — directly propor tional to concentration • Does 1 ml water samples directly with Hatch & Ott procedure • Accurate measurements well below the mini mum test standards currently recommended by government agencies • Dual-Beam system — cancels background ef fects • Highly-stable photometer—drift less than 0.0002 O. D. per hour Write, or call, for more information on the LDC mercury Monitor
LABORATORY DATA CONTROL P.O. Box 10235, Interstate Industrial Park Riviera Beach, Florida 33404 (305) 844-5241 CIRCLE 110 ON READER SERVICE CARD
Labware Cleaner
Micro Laboratory-Ware Cleaner has announced that it has removed all phos phates from its formula. The new cleaner is a quick-dissolving liquid, as in the past, but no longer separates in cold water; the price remains the same. International Products Corp. 609-3945480 503
KEEP G. C. COLUMNS AT PEAK EFFICIENCY with a fast injection of
Kits for Phosphorus and Calcium
Cal-Pak, for the titrimetric deter mination of calcium in serum and water, is based on the formation of a yellowgreen complex with a specially screened indicator for visual use. A color change from the yellow-green to blue reflects the removal of EDTA of Ca2+ from the complex. Optionally, the indicator system can be used for titrating to the disappearance of fluo rescence under longwave black light (3600 to 3660 A). Materials for 40 tests cost §15; 80 tests, $22.50, and includes reagents, standards, and de tailed procedure. Phospho-Pak is based on a colori metric method and requires trichloro acetic acid, molybdate, Pictol solution, and phosphorus standard. Complete sets of reagents, standards, detailed pro cedure, and %T conversion chart cost for 40 tests, $9.50; for 80 tests, $15. Uni-Tech. 201-859-2151 504
Inject a few microliters of Silyl-8®between runs on your G.C. and watch that base line settle d o w n ! Or, if a sample is going to pot on your column, no need to shut down your instrument several hours to condition the column; just inject Silyl-8 and in less than 5 minutes you're ready to go again. Silyl-8 is 100% active and is composed of three power ful silylating reagents. It acts by blocking active sites that have developed on your pack ing. Economical, too; each 1 ml hypovial is sufficient for 20 to 70 shots averaging less than 2 cents per shot. Useful for all types of columns except those with Η-bonding phases. 38014
SILYL-8 GLC Column Conditioner $10/pkg 12 χ 1 ml vials
Our silylation reagents are known the world over for their purity, efficiency and conven ience. The ready for use T R I - S I L ® f o r m u l a tions rapidly produce volatile and thermally stable derivatives for gas phase analyses in simple one step procedures. Our free 60 page booklet Handbook of Silylation des cribes these and other reagents, solvents and standards, lists methods and references and provides numerous suggestions and practical ideas. If you don't have a copy we'll be glad to send you one.
PIERCE CHEMICAL COMPANY P. O. Box 117 R o c k l o r d , Illinois 61105 PHONE 815/968-0747
TWX 9 1 0 - 6 3 1 - 3 4 1 9 .
CIRCLE 1 146 ON CIRCLE 46 O N READER SERVICE CARD
ANALYTICAL CHEMISTRY, VOL. 43, NO. 6, MAY 1971
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