Colouring Agents for Use in Disc-antibiotic Sensitivity Tests

Abstract
Discs of Whatman''s No. 1 filter paper 6.3 mm. in diameter are autoclaved or sterilized by dry heat in lots of 100 in 1 oz. universal containers. Equal parts of antibiotics (penicillin 200 U./ml.; chloramphenicol 5000 mg./ml.; aureomycin 10,000 mg./ml.; terramycin 2000 mg./ml.; sulfathiazole 100 mg./ml.) and dye solns. (5 mg./ml. of Ford red, 3:1 Ford yellow and Ford blue, Ford yellow, 1:1 Ford orange and Ford scarlet, or Ford blue, sterilized by steaming for 1 hr.) are mixed and added to each bottle of 100 discs. They may be stored at 4[degree]C, for several mos. without loss of potency. Streptomycin precipitates the dyes and therefore added to uncolored discs (10 mg. per disc).

This publication has 1 reference indexed in Scilit: