Among chemists, the morning coffee-break is a well-established custom. During these informal symposia much worth-while data are exchanged. We should like to sit in and tell you about some of our 600 plus Merck Laboratory Chemicals.
ISOBUTYL ALCOHOL . . . HELP OR HEADACHE?
I s o b u t y l alcohol as a solvent expe dites fluorometric d e t e r m i n a t i o n of t h i a m i n e in cereal a n d p h a r m a ceutical p r o d u c t s . U n f o r t u n a t e l y for t h e peace of m i n d of d r u g a n d food chemists, regular grades of isobutyl alcohol contain fluores cent impurities a n d , since these impurities h a v e a h a b i t of vary ing, correction factors are risky. Redistillation to accepted stand ards solves t h e problem, b u t is a tedious j o b for b u s y chemists. Chemists specifying M e r c k Iso b u t y l Alcohol avoid these head aches because our exclusive re agent grade solvent is specially purified for fluorometric assay and can be depended u p o n t o give ac curate, reproducible results.
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ROUNDING UP ALKOXY GROUPS WITH HI
N o organic microanalyst w a n t s to " f l u b " an alkoxy d e t e r m i n a t i o n .
T o rope a n d b r a n d t h e tricky and often elusive methoxyl a n d other alkoxy groups, we suggest you t r y M e r c k H y d r i o d i c Acid for meth oxyl determination. Our specs for high assay ( 5 5 - 5 8 % H I ) a n d high specific gravity (1.7) assure you of a p r o d u c t t h a t will hydrolyze all alkoxy groups present. M e r c k is p r o u d of its iodine compounds, b u t even our most critical control chemists feel t h a t we've surpassed ourselves with this item. Other grades of M e r c k Hydriodic Acid (with preservative) are available for t h e inorganic chemist inter ested in dissolving alkaline earth sulfates, mercuric iodide, a n d other so-called "acid-insolubles." NO MORE WASHDAYS FOR CHROMATOGRAPHERS
Chemists — par ticularly steroid chemists — who h a v e spent weari some h o u r s acidw a s h i n g alkaline alumina will wel c o m e t h e n e w e s t m e m b e r of M e r c k ' s g r o w i n g f a m i l y of c h e m i c a l s for c h r o m a t o g r a p h y : Acid-Washed Alumina. Chromatographers will find this p r o d u c t tailored to suit their needs for c h r o m a t o g r a p h i c analysis where
Precision Reagents for Accurate Analysis
alkaline alumina is unsatisfactory. F o r specs on other M e r c k chro matographic chemicals d r o p us a note a n d we'll send you some of our new technical d a t a sheets. NO TEARS WITH MERCK L-CYSTINE REAGENT
N u t r i t i o n experiments involving purified basal diets h a v e been known t o give inconclusive results after m o n t h s of work. Investiga tion usually reveals t h a t one of t h e ingredients contains significant a m o u n t s of biologically active con t a m i n a n t s . For greater a c c u r a c y use M e r c k A l p h a Amino Acids. T a k e our L-Cystine R e a g e n t for ex ample. B y phase solubility analysis it contains 9 8 - 1 0 0 % L- Cystine. S u c h high p u r i t y helps eliminate remorse, regrets, and recrimina tions a t t h e end of t h e feeding period. If y o u ' r e interested, we'll send d a t a on cystine a n d the 22 additional amino acids t h a t we offer.
MERCK LABORATORY CHEMICALS
M E R C K & CO., I N C . Manufacturing R A H W A Y ,
Chemists
N E W
J E R S E Y
Ο Mtrck & Co., Inc.
For further information, circle numbers 34 A-1, 34 A-2, 34 A-3, 34 A-4 on Readers' Service Card, page 43 A
34 A
ANALYTICAL
CHEMISTRY
