Pancreatin, solution preparation, with

After four or five days, with daily shakings, most of the casein is in solution and chalky masses of tyrosine begin to separate. After five days, a second dose of 20 g. of pancreatin in 100 cc. of water is added. After twelve days, the bottle is cooled in an ice-box over night and the undissolved material is filtered off (Note 4) and reserved for the preparation of tyrosine. 

Solutions of a pancreatin FIP standard preparation in physiological saline were diluted 1 1 with a solution of 8ft BSA, 0.9% NaCI and measured with this fast, comolfitelv automated method. The Ortho method yielded an excellent cor-... 

Standard Preparation Weigh accurately about 20 mg of USP Pancreatin Reference Standard into a suitable mortar. Add about 30 mL of pH 6.8 Phosphate Buffer, and triturate for 5 to 10 min. Transfer the mixture with the aid of pH 6.8 Phosphate Buffer to a 50-mL volumetric flask, dilute with pH 6.8 Phosphate Buffer to volume, and mix. Calculate the activity, in USP Units of amylase activity per mL, of the resulting solution from the declared potency on the label of the Reference Standard. 

There would appear to be at least two possible explanations for the discrepancy between the results of Schmidt and Levene and those of Kunitz regarding the dialyzability of the end-products. The first is that Schmidt used as enzyme a boiled solution of commercial pancreatin, whereas Kunitz employed crystalline ribonuclease which had not been exposed to heat. The second possibility has been pointed out by Loring and Carpenter. They consider that dialysis in the presence of the enzyme preparation, which probably contained an appreciable amount of inert protein, is not comparable with dialysis of a mixture of the four mononucleotides in the absence of the enzyme preparation. Simple control experiments would surely serve to establish the truth or falsity of these speculations. 

In the preparation of i -tryptophane from 600 g. of casein suspended in 3.2 1. of water at 37° by digestion with commercial pancreatin (two 20-g. batches), a solution of 60 g. of NajCOa and 6 g. of NaF in 100 ml. of water is poured in prior to addition of the enzyme as a thin paste in water. The mixture is covered with a layer of toluene, diluted to 6 I., shaken thoroughly, and let stand at 37° for 5 days a second butch of enzyme is added and the mixture let incubate for 12 days more. The sodium fluoride probably inhibits (he action of the oxidases. Workup affords 4.0-4.1 g. of pure I.-tryptophane and 17.0-18.2 g. of pure i.-tyrosine i.-tyrosine... 

Solutions of a pancreatin FIP standard preparation in physiological saline were diluted 1 1 with a solution of 8% BSA, 0.9% NaCl and measured with this fast, completely automated method. The Ortho method yielded an excellent correlation with the FIP pH-stat reference method Ortho U/L = 0.968 FIP U/L + 4.232 (r = 0.999). The recoveries in the low (294 FIP U/L), medium (440 FIP U/L), and high (734 FIP U/L) activity ranges were 101.1, 99.9, and 96.5%, respectively the intra-assay CVs were 3.0, 1.9, and 1.6% (n = 5). The detection limit, determined by a two-step dilution method and defined as the highest dilution that can be distinguished from the zero solution with 95% confidence, was 3.2 Ortho U/L. 

The intestinal fluid stimulant [2] consisted of a solution of pancreatin. First potassium dihydrogen phosphate (KH2PO4) (6.8 g) was dissolved in distilled water (250 ml) in a 1 litre volnmetric flask. Then 0.2 M sodium hydroxide (190 ml), sodium taurocholate (0.5 g), and distilled water (around 400 ml) were added. A solution of pancreatin (10 g, USP) was prepared separately by gradually adding the enzyme into distilled water (150 ml) to avoid the formation of lumps, and it was then transferred into the volumetric flask with gentle shaking. The pH was adjusted to 7.5 0.1 with sodium hydroxide (0.2 M), and the resulting solution was diluted to 1 litre with distilled water. 

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