Page:Defensive Ferments of the Animal Organism (3rd edition).djvu/226

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quite possible, for instance, that in any given case a quantity of highly molecular peptones is present in the dialysate. The biuret reaction is surprisingly strong, while the ninhydrin reaction, on the contrary, is very weak. Conversely, we can imagine the extreme case, in which the decomposition lies below the peptone limit. We obtain a deep blue ninhydrin reaction, which means that many compounds, having the structure of amino-acids, are present; whilst the biuret reaction gives a negative result. These facts show clearly, that the ninhydrin reaction enables us to recognize many more compounds of the group of albumen decomposites than the biuret reaction.

Certainly many points in the whole method of the dialysation process might be modified. In the first place, the apparatus used could be improved. One might consider, for instance, the possibility of constructing an apparatus, which would enable us to boil the solutions of the ninhydrin reaction simultaneously and equally, and at the same time to prevent any evaporation. We have purposely made no propositions in this direction, because it seemed to us, that the great advantage of the present method is just that it is simple, clear and concise. We have also made experiments for simplifying the preparation of the organs, and more particularly for shortening that process. Studies on organs, that had been dried and pulverized at 37° C. with special precautions,