No abstract

Tobramycin belongs to the aminoglycoside class of antibiotics. Assay procedures were investigated to determine the most suitable methods for the assay of tobramycin in blood, urine, and pharmaceutical preparations. The agar-plate assay was the method of choice for determinations in urine and serum. The turbidimetric assay was selected for the assay of pharmaceutical preparations. An extraction technique is described that minimizes problems encountered in the estimation of tobramycin in urine. Sample diluents, pH, and molarity were important and were variable depending on assay methods. Evidence is presented to show binding of tobramycin to a-cellulose susceptibility discs. Iron and sodium ions demonstrated potential inhibition of tobramycin in all assay methods tested.

No abstract

No abstract

Extracts possessing the capacity to hemagglutinate normal human erythrocytes were recovered from Haemophilus aegyptius by treatment with either diethylene glycol or acetone. Antisera prepared against these extracts or the unextracted bacterial cell inhibited hemagglutination by homologous and heterologous antigens. Microgel diffusions indicated the presence of identical components in each extract as expressed by lines of identity between antisera to each fraction. The hemagglutinin was identified as a lipopolysaccharide, 42% lipid and 57% carbohydrate. The determination of 6% phosphorus in the lipid fraction identified it as containing phospholipid.