McKEE-PEDERSEN INSTRUMENTS

CHEMICALS. Spectro-Check is a quality-control re- agent set consisting of four solutions to be used for monitoring the perform- ance of uv and visible...
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NEW CHEMICALS

'MethElute', 0.2M trimethylanilinium hydroxide in methanol, is our new methylating agent that derivatizes instantaneously and quantitatively when injected w i t h the sample into a gas chromatograph. This on-column methylation has received considerable publicity lately due t o its use in the detection o f barbiturates, 1 , 2 , 3 sedatives, 1 ' 3 xanthine bases,2 phenolic alkaloids 2 and D i l a n t i n . 3 * With the advent of this new reagent troublesome secondary peaks are eliminated, giving a single quantitative peak response t o the substance in question.

Spectra-Check is a quality-control reagent set consisting of four solutions to be used for monitoring the performance of uv and visible spectrophotometers. The solutions are supplied at working concentrations and can be transferred directly t o any cuvette or flow cell. Oxford Laboratories, Inc. 415-347-5291 429 Purified isomers of polychlorinated biphenyls are now available in purities above 9 9 % . These reference chemicals include the mono-, di-, tri-, tetra-, penta-, hexa-, and deca-isomers from 2-monochlorobiphenyl to 2,3,4,5,2', 4 ' , 5'-decachlorobiphenyl. Analabs, Inc. 203-288-3400 430 Fluoreze-M, a 0.8M solution of activated molybdenum fluoride in CH2CI2, will react at or below room temperature with aldehydes and ketones t o form gem-difluorides without pressure and in ordinary glassware. Research quantities cost $ 2 5 / 5 0 grams. Research Chemicals Div. 904-376-7522 431 Tic aerosol spray reagents for various classes of compounds such as sugars, carboxylic acids, alkaloids, amino acids, steroids, and lipids are available. The following Baker TLC reagents have been use-tested: p-anisidine phthalate, bromocresol green, 2', 7'-dichlorofluorescein, p-(dimethylamino)benzaldehyde, ninhydrin, phosphomolybdic acid, and rhodamine B. J. T. Baker Chemical Co. 201-859-2151 432 Radiometer buffers, ready-to-use, are available in 500-ml premium plastic containers providing accurate values ranging from 1.68 to 9.18 pH. For long shelf life, bottles are vacuum sealed in aluminum foil. Accuracy of the buffer is guaranteed, at the time of opening, to be within ± 0 . 0 1 pH at the specified temperature. The London Co. 216871-8900 433 Trace mercury in coal, SRM 1630, a new Standard Reference Material, can be used by coal users to determine accurately by comparison techniques the amount of mercury in the coal they are burning. This standard is a commercially available, low-bituminous coal ground to a particle size of 210—500 ^m and provisionally certified to have a mercury content of 0.13 ppm by weight. SRM 1630 may be purchased in 50gram units for $45 each from the Office of Standard Reference Materials, Rm. B314, Chemistry Bldg., NBS, Washington, DC 20234. 301-921-2045

NEW

INSTANTANEOUS ON-COLUMN METHYLATING AGENT.

We have prepared a four page technical bulletin describing the use of 'MethElute' in determining sedatives and showing sample chromatograms. If you'd like t o have one just drop a card or note t o our Literature Department. 'MethElute' is in stock f o r immediate delivery; it is packed in 10 ml Hypo-vials; please order as follows: 49300

' M E T H E L U T E ' , 10 ml

$12.50/each; 12 vials, $9.60/each

1. Chemical and Engineering News, page 13, April 12, 1971. 2. Brochmann-Hansen and Oke, J, Pharm. Sci., 58,370-371 (1969). 3. M. James Barrett, The Clinical Chemistry Newsletter, 3, No. 1, Spring 1971, published by Perkin-Elmer Corporation, Norwalk, Conn. * Dilantin is a trademark of Parke-Davis and Co. 'MethElute' is a trademark of Pierce Chemical Co.

PIERCE CHEMICAL COMPANY P.O. Box 117 Rockford, Illinois 61105 U.S.A. PHONE 815/968-0747 TWX 910-631-3419,

CIRCLE 156 O N READER SERVICE CARD

MPI

MODULAR SYSTEMS

FLEXIBLE ELECTROCHEMISTRY SYSTEM The MPI Building Block concept provides unusual versatility and performance with solid state reliability. This modular electrochemistry system accepts inputs from virtually any detector you provide and has over 60 applications to serve your needs. MP-System 1000 applications include: pH, Specific Ion, Polarography, Coulometry, Conductimetry, Auto Titrations, Potentiostats, Amperometry. MP-1666 Console (Includes Plug-in Modules) $1,999. MP-1027 10" Strip Chart Recorder 565. MP-1026 Potentiostat/50w Operational Amplifier 480. MP-1776 Electrometric System (Including Above and Accessories) 3,355. MP-1037 XY Recorder (not shown) 980. Write for MPI Catalog-Electrochemistry

Phone:415-937-3630

McKEE-PEDERSEN INSTRUMENTS, Box 322, Danville, Ca 94526 CIRCLE 1 2 6 O N READER SERVICE CARD

ANALYTICAL CHEMISTRY, VOL. 44, NO. 4, APRIL 1972



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