Utilizing the amphoteric nature of most sulfonamides, a simple extraction method followed by the colorimetric development, based on the diazotization-coupling reaction with N-(l-naphthyl) ethylenediamine dihydrochloride, is described for the determination of sulfonamides alone and in combination with procaine penicillin G in milk. Recoveries for the ten sulfonamides studied ranged from 81 to 100% recovery at the 100-p.p.b. level.

No abstract

The fluorescent property of metoserpate after reaction with nitrous acid is utilized for its determination in biological systems. The procedure can easily detect 5 p.p.b. of drug. A general procedure is given for tissues (kidney, liver, muscle, and fat) which is applicable with slight modifications to eggs and blood. Average recoveries were greater than 64% in fat and greater than 74% in all other biological systems. The average controls gave an apparent metoserpate concentration of 0 p.p.b. for eggs, 2 p.p.b. for blood, while the highest average control from tissue was 2 p.p.b.