NEW CHEMICALS
S t a b l e i s o t o p e s carbon-13 a n d helium-3 are available a t lower t h a n usual c o n c e n t r a t i o n s o f 20 a n d 90%, respectively. P r o d u c i n g t h e isotopes a t lower initial c o n c e n t r a t i o n s results in s i g n i f i c a n t price r e d u c t i o n s . A price list is a v a i l a b l e . M o n s a n t o Co. 314-694-2876 430 I n s t r a - A n a l y z e d s o l v e n t s , h i g h - p u r i t y sol v e n t s f o r i n s t r u m e n t a l analysis, q u a l i t y c o n t r o l , a n d g e n e r a l r e s e a r c h , have a m i n i m u m assay o f 99% purity. A new certificate of analysis w i t h t h e s e s o l v e n t s includes a n actual gas chromatogram, ir-absorbance curve, uv-absorbance c u r v e , a c t u a l lot analysis a n d values for absorbance a t selected wavelengths in t h e uv, t y p i c a l properties s u c h as b o i l i n g a n d f r e e z i n g p o i n t s , a n d use d a t a . J . T . Baker C h e m i c a l Co. 201-859-2151 431 FOD a n d DPM c h e l a t e s o f y t t e r b i u m , gadolinium, neodymium, sarmarium, d y s p r o s i u m , a n d e r b i u m have been a d d e d to t h e c o m p a n y ' s line of n m r s h i f t reagents. Bio-Rad Laboratories. 415234-4130 432 VYDAC a d s o r b e n t a n d VYDAC r e v e r s e p h a s e are t w o new p r o d u c t s f o r high speed liquid-chromatography separa t i o n s . VYDAC a d s o r b e n t is a s p h e r o i d a l solid particle c o a t e d w i t h silica w i t h a p p l i c a t i o n s i n t h e separation o f corticoste roids, n i t r o a r o m a t i c s , a n d a r o m a t i c alco hols. T h e reverse-phase m a t e r i a l is a n o c t a d e c y l silicone c h e m i c a l l y b o n d e d t o t h e s u r f a c e o f a VYDAC a d s o r b e n t - l i k e particle t o f o r m a solid c o r e , h i g h - s u r f a c e area, nonpolar, f r e e - f l o w i n g m a t e r i a l . Applications include t h e separation of fused-ring hydrocarbons. The adsorbent costs $117/25 g r a m s ; t h e reverse phase, $167/25 g r a m s . A p p l i e d Science Labora t o r i e s . 814-238-2406 433 Nuclear-magnetic resonance-shift re a g e n t k i t s c o n t a i n i n g four t o six c o m p o u n d s are available. T h e use o f t h e s e chelates o f t e n s i m p l i f i e s s t r u c t u r e d e t e r m i n a t i o n b y n m r . T h e c o m p a n y also offers t h e s t a r t i n g m a t e r i a l s f o r c h e l a t e s y n t h e s i s . PCR, Inc. 904-376-7522 4 3 4 I o n - e x c h a n g e c e l l u l o s e p o w d e r s for t h e chromatographic separation of biochem ical polyelectrolytes s u c h as p r o t e i n s , en z y m e s , a n d nucleic acids are b e i n g m a d e under the Whatman trade name. Two d i f f e r e n t m a t e r i a l s a r e available: carb o x y m e t h y l cellulose (cation e x c h a n g e r ) a n d d i e t h y l a m i n o e t h y l cellulose ( a n i o n e x c h a n g e r ) . T h e m a t e r i a l s are available preswollen as well as dry. W. & R. Balss t o n , Springfield Mill, M a i d s t o n e , K e n t , England
FAST QUANTITATIVE Fatty Acid Esterification These exciting new reagents offer signi technical bulletin is available on request; ficant advantages over other methods for just ask for "Alkyl-8 Bulletin." the preparation of alkyl esters and other Order as follows: derivatives for gas phase analysis. 49350 METHYL-8™, DMF DIMETHYLACETAL SPEED — Most reactions are c o m p l e t e 2 meq/ml in Pyridine $16/25ml as s o o n as s o l u t i o n is a c h i e v e d . 49330 ETHYL-8™, DMF DIETHYLACETAL C O N V E N I E N C E — One step procedure; 2 meq /ml in Pyridine $16/10ml 49360 PROPYLS™, DMF DIPROPYLACETAL ready-to-use reagents in Hypo-vials. 2 meq /ml. in Pyridine S16/10ml CHOICE O F DERIVATIVE - Methyl, 49310 n-BUTYL-8™, DMF-DI-n-BUTYLEthyl, Propyl, η-Butyl or t-Butyl; t-Butyl ACETAL esters are formed as easily as methyl 2 meq/ml in Pyridine S16'10ml esters. Q U A N T I T A T I O N - Quantitative 49320 t-BUTYL-8™, DMF-DI-t-BUTYLACETAL yields are obtained — even w h e n reagent 2 meq ml m Pyridine S16'10ml and sample are injected without prior mixing. PIERCE CHEMICAL COMPANY^ These significant new reagents may b e P.O. Box 117 Rockfofd, Illinois 61105 U.S.A. PHONE 8l5/96fl-0747 TWX 910-631-3419 ordered as listed in the next c o l u m n . A CIRCLE 173 O NREADER SERVICE CARD
New Price List!
Materials for: Ion exchange, Gel chromatography, Adsorption, Gel electrophoresis, Hollow fiber technique. Columns and Stable isotopes.
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Bio-Rad's P r i c e List X is t h e m o s t detailed guide published anywhere on materials for the t e c h n i q u e s listed a b o v e . New items featured in Price List X i n c l u d e H o l l o w Fiber Devices for desalting, concentrating and fractionating proteins, enzymes, viruses and other biomolecules.
You'll also find 3 new pages o n gel intermediates for affinity chromatog raphy a n d c o m ',ΒΙβ-RBB plete details o n materials and equipment for gel electrophoresis. A new a p p l i c a t i o n s index a n d a new easy-to-use for mat makes X our most useful cat alog yet. For your FREE copy, c o n t a c t :
BIO-RAD Laboratories 32nd & Griffin Ave., R i c h m o n d , CA 94804, Phone (415) 234-4130 Also i n : R o c k v i l l e Centre, Ν. Υ.; St. A l b a n s , E n g l a n d ; M i l a n o ; M u n i c h CIRCLE 24 ON READER SERVICE CARD ANALYTICAL CHEMISTRY, VOL. 4 4 , NO. 9 , AUGUST 1 9 7 2
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