New Products Chemicals Stable Isotopes
Collecting is an art.
Stable isotopes which have been sepa rated and enriched may be used for the manufacture of mass spectrometer standards. Available isotopes include helium-3, neon-20, neon-22, krypton82, xenon-124, carbon-13, nitrogen-15, oxygen-17, and oxygen-18. Isotec. Inc. 450
Chelating Ion Exchange Resin Chelex 100 purifies buffers and ionic reagents by removing metal ions with out altering the concentration of nonmetallic ions. The resin has a selectivi ty for divalent over monovalent ions of approximately 5000 to 1, and has a strong attraction for transition metals, even in concentrated salt solutions. Bio-Rad Laboratories 452 G l y c o h e m o g l o b i n Kit The Fast Hb Glycohemoglobin test kit is now cyanide-free. The ion exchange resin columns and the two hemoglobin elution solutions no longer contain cya nide. The omission of cyanide has im proved the performance of the test. Isolab Inc. 453
Standard for Potassium
The state-of-the-art LC fraction collector is Gilson's. The Gilson FC-220 is the preferred fraction collector for liquid chromatography because of its long record of reliable performance. This large capacity collector accommodates 220 test tubes in a variety of sizes: 18 χ 150 mm; 13 χ 100 mm; 17 χ 55 mm mini-vials. Three collection methods may be used—drop counting, time collection, or volume with an optional volumetric pump. Each rack is a "cube" containing 20 tubes, a configuration that avoids accidental tipping and loss of sample. The FC-220 includes an internal heater and components selected for reliable cold room operation to 0 degree C. over extended use. Other features which make the FC-220 a truly convenient collector include: 3-digit LED display; optional shut-off valve to stop column flow during tube change; multiple collection for 2, 3, 4, or 5 columns; 220 collections unattended, or continuous collection. For literature (or better yet a demonstration from a qualified Gilson representative), call or write:
(Φ) GILSON
Box 27 Middleton. Wisconsin 53562 Phone (608) 836-1551
Serving research laboratories for more than a quarter of a century CIRCLE 88 ON READER SERVICE CARD 416 A ·
ANALYTICAL CHEMISTRY, VOL. 52, NO. 3, MARCH
1980
An assay-isotopic standard for potassi um, Standard Reference Material 985, may be used for the calibration of iso tope ratio mass spectrometers. This SRM is supplied as highly purified po tassium chloride and is certified for assay (99.9%) and for isotopic compo sition. Price, $58 per 1.0 g sample. Of fice of Standard Reference Materials, Room B311, Chemistry Bldg., National Bureau of Standards, Washington, D.C. 20234 Mineral Glasses Standard Reference Material 470, min eral glasses for microanalysis, is a set of two homogeneous glasses (K-411 and K-412) which are composed of Si0 2> FeO, MgO, and CaO; and Al 2 0 3 in the case of K-412. These glasses should be useful for quantitative analy sis of naturally occurring minerals, glasses, and ceramics. Extensive ho mogeneity testing has been done for all elements except oxygen. SRM 470 in cludes one rod of each glass. A rod is approximately 1 mm X 1 mm X 15 mm. Price, $185. Office of Standard Reference Materials, Room B311, Chemistry Bldg., National Bureau of Standards, Washington, D.C. 202.34