SEROLOGICAL REAGENTS 311 



BAGTO-GOMPLEMENT (B383) 



Bacto-Complement is fresh guinea pig serum dried from the frozen state. It 

 is prepared by pooling sera of a large number of mature, well-nourished guinea 

 pigs. It will retain its potency for a minimum of one year if kept at — 5°C. (the 

 freezing chamber of the refrigerator). The pooling of the large numbers of sera 

 as used in the preparation of Bacto-Complement eliminates the possibility of 

 non-specific reactions with antigens used in the complement-fixation test. 



Bacto-Complement is reconstituted by adding 5 ml. of Bacto-Complement 

 Reconstituting Fluid, using a clean sterile syringe to make the transfer. Rotate 

 the bottle to effect complete solution of the complement. This solution will 

 retain its potency for two to three weeks if stored in the freezing compartment 

 of the refrigerator. After thawing the frozen solution, avoid unnecessary exposure 

 to room temperature. 



Bacto-Complement is recommended for use in all complement-fixation tests. 

 Variables encountered in performing these tests necessitate that the complement 

 be titered just prior to use with the same reagents employed in the test. 



It has been shown that the use of a satisfactory saline is of utmost importance 

 in the performance of complement-fixation tests. In many localities the use of 

 tap water for the preparation of saline is preferred over distilled water. The titer 

 of complement is often improved by incorporating 0.1 gram of magnesium 

 chloride or magnesium sulfate per liter of tap or distilled water saline, resulting 

 in more clear-cut complement-fixation reactions. 



Bacto-Complement is supplied in 5 ml. amounts in vials. Each vial is accom- 

 panied with 5 ml. of Bacto-Complement Reconstituting Fluid. 



REAGENTS FOR PRECIPITATION 



TESTS 



BAGTO-KAHN STANDARD ANTIGEN (B218) 



Precipitation tests during the past thirty years have gained in interest and use 

 as diagnostic agents in syphilis. The Kahn test, described in 1923, was the first 

 practical precipitation test to gain wide usage. It is readily performed, rapid and 

 accurate. 



Bacto-Kahn Standard Antigen is prepared according to Kahn's directions^ '^-^ 

 and is a highly sensitive and specific reagent. Each lot is standardized to the same 

 standard degree of sensitivity and specificity. No lot is released without approval 

 from Dr. Kahn's laboratory. The antigen is stable and should be kept tightly 

 stoppered in the dark at room temperature. Bacto-Kahn Standard Antigen is 

 used in the standard and quantitative Kahn procedures with serum and spinal 

 fluid and is also used in the Universal Reaction of Kahn.^'^ 



iKahn: The Kahn Test, A Practical Guide, *Kahn: Serology with Lipid Antigen, i and 



76:1928. 24:1950. 



2 Kahn : Technique of the Standard Kahn 6 Kahn : An Introduction to Universal Sero- 

 Test, Univ. Mich. Press, 39- '944- logic Reaction in Health and Disease, 1951. 



3 Kahn : Serology with Lipid Antigen, 

 271:1950. 



