Enzymes 221 



0.05 M BARBITAL BUFFER 



1.03 g. of Na barbital in 50 ml. + x ml. of O.IN HCl. diluted to a 

 total volume of 100 ml. 



Barbital buffers of higher molarity than 0.05 M should not be used 

 because barbituric acid will precipitate, especially in the lower ranges 

 of pH. 



0.2 M 2-AMINO-2-METHYL-l,3-PROPANEDIOL BUFFER 



2.1 g. substance (Commercial Solvents Corp., New York 17) in 50 

 ml. + X ml. of N HCl, diluted to a total of 100 ml. 



0.2 M BORATE BUFFER 



Solution A: 1.24 g. of boric acid in 100 ml. 



Solution B: 1.9 g. of borax (Na2B407 • IOH2O) in 100 ml. 



