Application of author's precipitation test to spinal fluids.

This paper will give a resumé of the author's test for syphilis as applied to serum 1 and an outline of the application of the test to spinal fluids.

1. ANTIGEN

1. Preparation of Alcoholic Extract: Beef heart muscle is ground, dried and powdered in a manner usually employed for antigen preparation. 2 About 50 gm. of powdered muscle are placed in a 500 cc. Erlenmeyer flask and about 250 cc. ether added and shaken. This is extracted over night at icebox temperature. The ether is filtered off and about 150 cc. fresh ether added to the powdered muscle. Extraction is further carried on over night in the icebox. After 3 or 4 ether extractions, the supernatant ether is practically free from coloring matter, when the extraction is completed. The ether is then filtered off and the powdered muscle is dried at room temperature until free from ether odor. The ether extracts are either discarded or the ether redistilled.

The dried material is weighed; placed in a 500 cc. Erlenmeyer flask, and 5 cc. of 95 per cent alcohol added per gram of material. This alcohol extraction is carried out for about 10 days at icebox temperature with daily shaking. After this period, the extract is filtered off and kept in the dark as stock solution. 3

2. Cholesterinization of Alcoholic Extract: A given amount of extract (enough for about a month's use) is measured into an Erlenmeyer flask and cholesterin added to it in the proportion of 6 mg. per cc. The cholesterin is dissolved by warming the flask in the water bath and rotating. The cholesterinized extract is then filtered to free it from impurities, when it is ready for use in the tests.