New pharmaceutical compound of gelatin and tannin.

  • Aktiengesellschaft für Anilinfabrikation.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: New pharmaceutical compound of gelatin and tannin. Source: Wellcome Collection.

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    2 N° 11,061.— A. D. 1898. Abel's New Pharmaceutical Compound of Gelatin and Tannin. COMPLETE SPECIFICATION. 15 20 New Pharmaceutical Compound of Gelatine and Tannin. I, Charles Denton Abel, of Birkbeck Bank Chambers, Southampton Buildings, in the County of London, Consulting Engineer and Chartered Patent Agent, do hereby declare the nature of this invention (as communicated to me from abroad by The Actien-Gesellscliaft fur Anilin-Eabrikation, of Berlin, in the German Empire, Chemical Manufacturers) and in what manner the same is to be per- 5 formed to be particularly described! and ascertained in and by the following statement; —• It is w^ell known that the compound of gelatine and tannin is putrescible while the corresponding compounds derived from other tannic acids are not. My foreign correspondents have now discovered that this property is essentially jo caused by the water retained by the raw precipitate obtained from solutions of gelatine arffi tannin. Consequently if this water is removed by heating the precipitate up to 100° C. or even for a short time at more elevated temperatures a stable and non-putrescible product is obtained!, which can therefore be used for medicinal purposes. My foreign correspondents have discovered that it may be applied as an astrin¬ gent acting only in the intestines, as it is insoluble or hardly soluble in the juices' of the stomach while it is attacked by the alkaline juices of the intestines. There is however, another difficulty in obtaining this gelatine tannate in a form proper for medicinal purposes. As the gelatine tannin precipitate, even after the mother lyes have been removed by pressure, retains large quantities of water, it melts at relatively low temperature, a viscous and leatherlike mass being formed which it is very difficulty to dry completely and to pulverize. By heating the same for a long time on the water bath it is possible to remove the water, but the product obtained 25 in this way is not only strongly coloured but decomposes' much more readily than pure gelatine tannate, and assumes a disagreeable taste and smell when heated above 100° C. (for instance in order to sterilize it or to render it even more resistant to the stomach juices). These inconveniences are specially experienced if larger quantities of gelatine- on tannate are dealt with in one operation. Now my foreign correspondents have discovered that the melting of the raw precipitate may be avoided by allowing the latter to lie in the open air and at ordinary temperature for about 24 hours. Thereby nearly all water is removed and the remaining powder may be completely dried on the water bath without ^ melting. In order to remove the last traces of water it is advisable to dry finally at higher temperatures not exceeding 150° C. The product thus obtained may be pu prised without any difficulty. It is almost colourless and has no taste or smell. Ihus it is completely fit for medicinal purposes'. The following example may illustrate the manufacture of the new product: the gelatine-tannin precipitate required is produced by adding 200 litres of a 0 per cent solution of tannic acul to 1000 litres of a 1 per cent, solution of gelatine while constantly stirring. rt has been found advantageous to use diluted solutions of gelatine and tannin as the precipitate thus obtained separates in a more powder-like form and can much more easily be freed from the mother lyes, than when it is produced from more concentrated solutions. ^ u irom The gelatine-tannin precipitate is filtered off, washed repeatedly with water until the excess of tannic acid is removed, and pressed. 5U 40 45