[401] Pflüger’s Archiv., 23, 433, 413-433. Chem. Soc. Journ., May 1882, 543.
[402] Arch. Pharm., pp. [3], vii. pp. 23-26.
[403] Kauzmann, Beiträge für den gerichtlich-chemischen Nachweis des Morphia u. Narcotins, Dissert., Dorpat, 1868. Dragendorff, Pharm. Zeitschr. f. Russland, 1868, Hft. 4.
[404] Würtbg. Correspondenzbl., xxxiv. 16, 1863.
On the other hand, in a case recorded at [p. 304], where a woman died in six hours from a moderate dose, probably of laudanum, although the quantity of blood operated upon was over a pound in weight, and every care was taken, the results were entirely negative. In poisoning by laudanum there may be some remaining in the stomach, and also if large doses of morphine have been taken by the mouth; but when morphine has been administered hypodermically, and in all cases in which several hours have elapsed, one may almost say that the organ in which there is the least probability of finding the poison is the stomach. It may, in some cases, be necessary to operate on a very large scale;—to examine the fæces, mince up the whole liver, the kidney, spleen, and lungs, and treat them with acid alcohol. The urine will also have to be examined, and as much blood as can be obtained. In cases where all the evidence points to a minute quantity (under a grain) of morphine, it is decidedly best to add these various extracts together, to distil off the alcohol at a very gentle heat, to dry the residue in a vacuum, to dissolve again in absolute alcohol, filter, evaporate again to dryness, dissolve in water, and then use the following process:—
§ 365. Extraction of Morphine.—To specially search for morphine in such a fluid as the urine, it is, according to the author’s experience, best to proceed strictly as follows:—The urine is precipitated with acetate of lead, the powdered lead salt being added to the warm urine contained in a beaker on the water-bath, until a further addition no longer produces a precipitate; the urine is then filtered, the lead precipitate washed, and the excess of lead thrown down by SH2; the lead having been filtered off, and the precipitate washed, the urine is concentrated down to a syrup in a vacuum. The syrup is now placed in a separating tube (if not acid, it is acidified with hydrochloric acid), and shaken up successively with petroleum ether, chloroform, ether, and, lastly, with amylic alcohol (the latter should be warm); finally, the small amount of amylic alcohol left dissolved in the liquid is got rid of by shaking it up with petroleum ether. To get rid of the last traces of petroleum ether, it may be necessary to turn the liquid into an evaporating dish, and gently heat for a little time over the water-bath. The acid liquid is now again transferred to the separating tube, and shaken up with ether, after being made alkaline with ammonia; this will remove nearly all alkaloids save morphine,—under the circumstances, a very small quantity of morphine may indeed be taken up by the ether, but not the main bulk. After separating the ether, the liquid is again made slightly acid, so as to be able to precipitate morphine in the presence of the solvent; the tube is warmed on the water-bath, at least its own bulk of hot amylic alcohol added and the liquid made alkaline, and the whole well shaken. The amylic alcohol is removed in the usual way, and shaken with a small quantity of decinormal sulphuric acid; this washes out the alkaloid from the amyl alcohol, and the same amyl alcohol can be used again and again. It is best to extract the liquid for morphine at least thrice, and to operate with both the solution and the amyl hot. The decinormal acid liquid is made slightly alkaline with ammonia, and allowed to stand for at least twelve hours; any precipitate is collected and washed with ether, and then with water; the alkaline liquid from which the morphine has been separated is concentrated to the bulk of 5 c.c. on the water bath, and again allowed to stand for twelve hours; a little more morphine may often in this way be obtained.
The author in some test experiments, in which weighed small quantities of morphine (60-80 mgrms.) were dissolved in a little decinormal sulphuric acid, and added to large quantities of urine, found the process given to yield from 80 to 85 per cent. of the alkaloid added, and it was always recovered in fine crystals of a slight brown tint, which responded well to tests.
Various other methods were tried, but the best was the one given; the method not only separates the alkaloid with but little loss, but also in a sufficiently pure state to admit of identification.
From the tissues the alkaloid may be dissolved out by the general method given at [p. 239], and the ultimate aqueous solution, reduced to a bulk of not more than 25 c.c., treated by the ethereal solvents in the way just described.