BS016 

VITAMIN B12 ASSAY MEDIUM

Formula

Ingredients 

gms/lit.

Casein acid hydrolysate 

Dextrose

Aspargine 

Sodium acetate 

Ascorbic acid 

L-cystine 

DL-tryptophan 

Adenine sulphate 

Guanine hydrochloride 

Uracil 

Xanthine 

Riboflavin (vitamin B2) 

Thiamine hydrochloride

Biotin 

Niacin 

p-Amino benzoic acid

Calcium pantothenate 

Pyridoxine hydrochloride 

Pyridoxal hydrochloride

Pyridoxamine hydrochloride 

Folic acid 

Monopotassium phosphate 

Dipotassium phosphate 

Magnesium sulphate 

Sodium chloride 

Ferrous sulphate 

Manganese sulphate 

Polysorbate 

15.00

40.00

0.20

20.00

4.00

0.40

0.40

0.02

0.02

0.02

0.02

0.001

0.001

0.00001

0.002

 0.002

0.001

0.004

0.004

0.0008

0.0002

1.00

1.00

0.40

0.02

0.02

0.02

80 2.00

Final pH (at 25°C) : 6.1 + 0.2

Directions 

Suspend 8.5 gms. in 100ml. distilled water. Boil to dissolve the medium completely. Mix well to distribute the slight precipitate evenly. For the assay, dispense 5 ml. medium to each assay tube (containing increasing amounts of standard of the unknown).Total volume of 10 ml per tube is adjusted by addition of distilled water. Sterilize by autoclaving at 15 lbs pressure (121°C) for 5 minutes. Cool the medium immediately. Generally satisfactory results are obtained with Vitamin B12 (cyanocobalamin) at levels 0, 0.025,0.05,0.075,0.1,0.125,0.15,0.2 ng per assay tube (10ml.)

Print This page

Close Window