Altex Scientific

High Performance Liquid Chromatography. All separations were performed using an Altex Scientific (1780 Fourth Street, Berkeley, CA 94710) Model 320 Advance Research Chromatograph, consisting of a model lOOA dual piston analytical pump, a Model 153 UV detector, a Model 210 injection valve, and a Model 155 recorder. The columns (600 x7.5mm) evaluated were the Spherogel TSK-SW-2000 and SW-3000 (Altex). Unless otherwise stated, all separations were carried out at 23 - 25 . 

Altex Scientific Inc., 1450 Sixth Street, Berkeley, Calif. 94710, U. S. A. 

Altex Scientific Inc., 1780 Fourth Street, Berkeley, Calif. 94710, U. S. A. DuPont de Nemours, Instrument Products Division, 1007 Market Street, Wilmington, Del. 19098, U. S. A. 

Beckman Instruments, Altex Scientific Operations, Berkeley, California... 

Toya Soda Manufacturing Co. Ltd., Tokyo, Japan Varlan Associates, Walnut Creek, California Bio-Rad Laboratories, Richmond, California Beckman (Altex) Scientific, Berkeley, California... 

Alitech Assoc. Inc. , 2051 Waukegan Road, Deerfield, IL 60015, USA Altex Scientific (Division of Beckman) , 1780 Fourth Street, Berkeley, CA 94710, USA II... 

FIGURE 18 Separation of catecholamines and interfering compounds. Ultrasphere C-18 column, 25 cm x 4.6 mm, mobile phase 10% methanol, 90% 0.1 M potassium phosphate, pH 3.0, 0.2 rr M sodium octylsulfonate, at 0.72 V vs Ag/AgCI reference electrode, sample size 20 /xl. Peaks (1) Ascorbic acid, (2) Dihydroxyphenylglycol, (3) Norepinephrine (4) Epinephrine, (5) Hydroxymethoxyphenylglycol, (6) Dihydroxybenzylamine, (7) Normetanephrine, (8) Dopamine, and (9) Dihydroxybenzylamine. [Reprinted from permission from Beckman/Altex Scientific.]... 

The modular HPLC system used in this study included the following components a Model IlOA Altex pump (Beckman Scientific Instruments) or a System 4 Series programmable pump (Perkln-Elmer Corporation), an In-line filter, a Model 773 variable-wavelength DV detector (Kratos Scientific Instruments) fitted with a 12 pL flow cell, a Model 600 Series autosampler with a nominal volume of 20 pL (Perkin Elmer Corporation) and a two channel recorder (Kipp and Zonen). The chromatographic data were processed with the aid of a Model 3357 laboratory computer (Hewlett-Packard). 

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