The specificity of the nitromethane-Hyamine procedure for the determination of nitrofurantoin in urine.

I .. ECENTLY, a new analytical method (imitroinetimaime-Hyamine) for the deternimnation of nitroful-alltoin (Furadantin*) in urilme was presented (1). Occasiomiallv, during mtrofurantoill nmedicatioii, anothei alltil)actonal is administered concomitantly (2-8). Such them-apeutic regimen necessitates mnfoi-matioim regarding the possible interference of other alltinhicrol)ials with time determination of iiitrofui-antojn by the nitroInetimalie-Hyanhmne procedure. Oime milliliter of aim aqueous solution containing 50 j.ig./nml. of each antibacterial exanmine(l was suh ected to time imitromethane-Hyamine procedure (1). This method consists of the direct extraction of the nonionized form of nitrofuraiitoiii by time mISc of mtromethaime, the ad(lition of an alkaline reagent (Hyamine) to time extract to produce a Visil)le color, aih(l the (leternmnlation of the niti-ofui’antoin concentration inspecti-ophotometry at 400 m . None of time following antibacterial agents exhmibited a visible coloi-, suggesting timat their presence should not iimtei-fere witlm timis analytical procedure : polymyxin B sulfate (Aerosporin), tetracycline hvdroclmlonide (Achromycimm), chloramphenicol (Chloi-omycetiim), cohistimethate sodium (Coly-Myciim), erythromycm ethyl succinate (E1-ythrocilm), sulfisoxazole (Gantnisiri), kanamycin sulfate (Kantrex), metlmenamine mandelate (Mandelamirie), nalidixic aci(l (NegGram), neomycin sulfate, penicillin (T potassiunm, sodium oxacillin (Prostaphliii), streptomnvcin sulfate, and oxvtetracvcline