Chloride of soda is a delicate test for the presence of guaiac resin. {11} Added to an alcoholic solution, a beautiful green color appears, while it produces no effect on scammony resin. This reaction is very evident, though transient, when a very small proportion of guaiac is present. Nitrate of silver causes a blue color in a solution of guaiac resin, as does also sesqui-chloride of iron, neither of which agents affects the color of a solution of scammony resin. In fact, the evidences of the presence of guaiac are so numerous and distinct that there can be no possibility of an undetected adulteration with this substance.
The high price of resin of jalap would seem to be sufficient to prevent its being resorted to as a means of sophisticating scammony; but in case this substance should be made use of, the method proposed for detecting it by means of ether is defective, since, according to authorities, resin of jalap is partially soluble in that substance.
It becomes of interest to know whether in the preparation of scammony the juice of the plant from which it is obtained is ever mixed with that of other plants of similar properties, or with that of plants destitute of efficacy. This information can, of course, only be furnished by those familiar with the localities and with the mode of its preparation.
[1]“In advancing the opinion that scammony should only be employed for therapeutic purposes in the state of resin, I mean that this resin should only be prepared by the apothecary himself. When, however, it is impossible for the apothecary to do so, and the commercial article is in consequence resorted to, there arises a liability to deception. We must then be enabled to recognise its purity.
To avoid detection of the fraud, the admixture must either be in small quantity, or it must possess nearly the same action. In this latter case, resin of jalap would be employed as being less in price and nearly as active.
The method I propose for detecting an adulteration of this nature, in case it should be attempted, is based on the one side upon the entire insolubility of resin of jalap in rectified sulphuric ether, and on the other, upon the solubility of scammony resin in this liquid. Nothing is easier than the detection of a mixture of these two resins, since eight grammes of ether dissolve completely ten centigrammes of scammony resin. {12}
Thus by agitating for a short time a mixture of twenty centigrammes of suspected resin with sixteen grammes of sulphuric ether, we shall be certain of the presence of resin of jalap, provided there is no other admixture, if a portion remains undissolved. This undissolved portion, dried and weighed, gives the proportion of the two resins.
Other more culpable sophistications may be attempted, either by the addition of resin of guaiac, or by that of colophony or other substances.
The resin of guaiac may easily be detected by means of the solution of gum, which I have specified as one of the most certain re-agents (Repertoire du Pharmacien, vol. iv., 1848), or by the means of nitrous gas, or bichloride of mercury.
Many re-agents disclose the presence of common resin or of pitch in the resin of scammony. First, spirits of turpentine, which dissolves the common resin at the ordinary temperature, and which leaves scammony resin almost untouched. The most certain re-agent, however, in my opinion, is sulphuric acid. This acid possesses the property of dissolving many resins—modifying their composition more or less.
Thus, if a small quantity is poured on common resin, an intense red color is produced by contact; poured on scammony resin, on the contrary, it does not produce an immediate change; only after some minutes, and with exposure to the air, does it become colored, and then but feebly, with the production of a color resembling the lees of wine, while in the first case the color is a very deep scarlet.
By this method one twentieth part of colophony may be detected in scammony resin. It is sufficient to pour upon twenty-five or thirty centigrammes of resin, placed in a glass or porcelain mortar, four or five grammes of commercial sulphuric acid, and to give one or two turns of the pestle; if colophony is present, the mixture will redden immediately upon contact; if, on the contrary, it is pure, the liquid will only become colored after the lapse of some time.
Colophony being more soluble in sulphuric acid is acted upon with more rapidity.”
[2]“Scammony resin obtained by alcohol of 86 degrees occurs in form of powder or in thin transparent scales, if the alcoholic solution has been evaporated on a stove upon plates, or upon sheets of tin. {13}
It is characterized by the peculiar odor of the substance from which it is obtained, the odeur de brioche, or of rancid butter.
If scammony resin has been mixed with one twentieth of common resin, trituration in a mortar developes the odor of the latter to a sufficient degree to cause detection of the fraud. Heated in a tube, a peculiar odor manifests itself with sufficient distinctness to indicate its purity.
This pure resin is soluble in all proportions in ether of 56 degrees (·752). This property affords a means of purifying it, by means of which it is obtained in thin flakes, by exposure to the air on plates.
Solution of ammonia at 24 degrees (·910) dissolves scammony resin completely. The solution has a more or less green color. These different properties, which the resin of scammony, obtained by alcohol, possesses, are sufficiently distinct to assist in distinguishing it from other resins or to establish its purity.”
December, 1851.
[1] Methods for detecting Resin of Jalap, Resin of Guaiac, and Colophony, in Resin of Scammony. By MR. THOREL.—From the Journal de Pharmacie et de Chimie, for Nov. 1851.
[2] Note by MR. DUBLANC.—From the Journal de Pharmacie et de Chimie, Nov. 1851.
ON THE PREPARATION OF STRAMONIUM OINTMENT. BY EUGENE DUPUY, PHARMACEUTIST, NEW YORK CITY.
The powerful narcotic and sedative properties of the Datura stramonium; added to the fact of its luxuriant growth in the vacant grounds of the inhabited districts of the United States, has made its use popular with most of our practising physicians. Besides its use smoked as tobacco in asthmatic cases, its properties analogous to those of hyosciamus and belladonna, have enabled practitioners to use it with success for producing dilatation of the pupil and in anodyne fomentations. In fact, the consequence of its demonstrated efficient activity as a remedial agent, has prompted its adoption in the United States Pharmacopœia, where the leaves and seeds are recognised, and the Tincture, Extract, and Ointment are officinal. According to our Pharmacopœia, last edition, to prepare the ointment, one drachm of the extract of stramonium is mixed to the proportion of one ounce of lard. Such a mixture, though possibly as effectual as need be, lacks the green color and homogeneity to which both patients and physicians have been accustomed. To remedy these objections, I have found the {14} following process to give a good preparation both in quality and appearance. I am inclined to think that the objections which have been made to the former officinal ointment are chiefly ascribable to the difficulty of obtaining readily an ointment which would keep one year, that is free from water of vegetation or not impaired by a too protracted ebullition, and consequent decomposition, which deprives it of its properties, spoiling its appearance, and giving it an unpleasant pyrogenous odor, which shows the extent of the alteration it has undergone, making of it an irritating rather than a soothing unguent. In the process I now submit to the opinion of the profession, I had in view, 1st. To obtain at all seasons an ointment fulfilling the reasonable expectations of practitioners; 2d. Which could be easily prepared by competent Pharmaceutists throughout the United States. It is as follows: