THELCCOLUMN new z-or oax w o expands reversed-phase capabilities. Zorbax™ C-8 is the newest mem ber of the Du Pont line of bonded phase packings based on Zor bax™ technology. It is produced with the same unique methods as Zorbax™ ODS and Zorbax'" CN, resulting in a reproducible chromatographic packing with maximum surface bonding. Zor bax™ C-8 gives you greater capa bility for a wider range of reversed-phase applications, and it complements the proven per formance of Zorbax™ ODS. Zorbax™ C-8 has greatest utility in separations of highly polar compounds, including water sol uble materials. For example, pro cainamide, a c o m m o n l y used cardiac depressant, can be readi ly separated f r o m a c o m m o n d e r i v a t i v e w i t h Zorbax™ C-8 (Figure 1). This separation is
Figure 1 Column: Zorbax" C-8, 4 6 mm ID χ 25 cm Mobile Phase: 3 5 % CH.CN/ 65% NahbPO. (.020 M). p H 3 . 3 PEAK IDENTITY 1. Procainamide 2. n-acetyl procainamide
TIME (min)
Nov./Dec. faster and results in better reso lution and peak shape than that achieved with a C-18 column. Zorbax'" C-8 is available in 4.6 mm ID columns in both 15 cm and 2 5 cm lengths. As with all Zorbax"* based products, Zor bax'" C-8 columns are pretested and guaranteed to meet rigorous specifications.
Sulfa drugs separated by Loruax \-~o. Figure 2 Column: Zorbax1" C-8. 4.6 mm ID χ 25 cm Mobile Phase: 40% C H C N / 60% NaHrfO. (.020 M), p H 3 . 3
PEAK IDENTITY 1. Sodium Sulfathiazole 2. Sulfacetamide 3. Sulfamerazine 4. Sulfisoxazole 5. Sulfabenzamide
u
salts, ethylene copolymers, dental fill ings, thin films, a n d gun propellants are reported. T h e book is a photo-off set copy of typewritten text.
U.S. Government Publications Free copies of the following are avail able upon request to: William J. Campbell, Bureau of Mines, College Park Metallurgy Research Center, College Park, Md. 20740 Bureau of Mines Report of Investiga tions 8244, Metals in the Combustible Fraction of Municipal Solid Waste. B. W. Haynes, S. L. Law, and W. J. Camp bell. This report summarizes sampling, analytical methods, and data on 23 ele ments in the combustible fraction of urban refuse. Bureau of Mines Information Circular 8751, Selected Silicate Minerals and Their Asbestiform Varieties: Defini tions and Identification-Characteriza tion. W. J. Campbell, R. L. Blake, L. L. Brown, E. E. Cather, and J. J. Sjoberg. This report is intended to clarify some of the terminology used in identification and characterization of asbestiform minerals, and to sharpen the distinction between common rock minerals and their asbestiform varieties.
TIME (min)
A series of closely related sulfa drugs is readily analyzed with Zorbax™ C-8 (Figure 2). These materials are sparingly soluble in organic solvents but have much greater solubility in water. Materi als with this solubility profile are excellent candidates for analysis by Zorbax™ C-8. Ask your DuPont Technical Rep resentative in HPLC about all the benefits of this new packing, or circle reader service card number 45 for more information.
Order columns by telephone · All DuPont columns and pack ings, as well as instruments, may be ordered via toll-free number 8 0 0 - 4 4 1 - 7 5 0 8 (in Delaware 772-5500). This toll-free number
Books
is for the exclusive use of conve nient ordering of these products. DuPont Instruments, Room 3 6 0 3 4 , Wilmington, DE 19898.
Du Pont Instruments CIRCLE 45 O N READER SERVICE CARD 1176 A · ANALYTICAL CHEMISTRY, VOL. 4 9 , NO. 13, NOVEMBER 1977
ASTM Publications The following is available from the American Society for Testing and Materials, 1916 Race St., Philadel phia, Pa. 19103 (USA, Canada, and Mexico add 3% shipping charges. Other countries add 5 %. 1977 Annual Book of ASTM Standards, Part 42: Emission, Molecular and Mass Spectroscopy; Chromatography; Resinography; Microscopy. 544 pages. 1977.$17 Of t h e 66 standard methods pre sented in P a r t 42, nine are new, re vised, or changed in status since t h e 1976 edition. Among t h e new standard methods are x-ray emission spectrometric analysis of stainless steel, rec ommended practices for internal re flection spectroscopy, test for linearity of fluorescence measuring systems, test for minimum detectable fluores cence of quinine sulfate a n d cyclohexane, a n d recommended practice for testing flame ionization detectors used in gas chromatography. In addition, 28 standards incorporate title and scope changes.
