ABSTRACT
A new high-performance size-exclusion chromatography method has been developed for the determination of potency of human growth hormone products. This method has been extensively validated and shown to correlate well with the hypophysectomized rat bioassay which has been used traditionally. The method is much more precise than the traditional bioassay and thus provides more reliable means of producing consistent biosynthetic human growth hormone batches.
Subject(s)
Growth Hormone/isolation & purification , Animals , Body Weight/drug effects , Cartilage/drug effects , Cartilage/growth & development , Chromatography, Gel , Chromatography, High Pressure Liquid , Growth Hormone/pharmacology , Humans , Indicators and Reagents , Rats , Reference Standards , Spectrophotometry, UltravioletABSTRACT
An isocratic reversed-phase high-performance liquid chromatographic method for the determination of human growth hormone (HGH) purity is described. This method offers superior resolution of HGH-related substances (e.g., sulfoxide and desamido derivatives) from unmodified HGH when compared to a number of alternative chromatographic and electrophoretic techniques.
Subject(s)
Growth Hormone/analysis , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Growth Hormone/biosynthesis , HumansABSTRACT
A method is described for the simultaneous determination of the experimental insecticide nifluridide (N-(2-amino-3-nitro-5-(trifluoromethyl)phenyl)-2,2,3,3-tetrafluoropropanamide) and its cyclized product, EL-919 (7-nitro-2-(1,1,2,2-tetrafluoroethyl)-5-(trifluoromethyl)benzimidazole), in water. Both compounds are extracted by passage of up to 500 mL water through two Sep-Pak C18 cartridges joined in series. The extraction is automated by using vacuum. The compounds are eluted from the cartridges with acetonitrile. Both compounds are then separated and measured by high pressure liquid chromatography with UV detection at 235 nm. Recoveries were 91.2-97.1% nifluridide and 82.7-98.0% EL-919 for deionized water samples fortified with 0.001-0.1 ppm nifluridide and 0.005-0.1 ppm EL-919. Analysis of water samples (pH 8) from bluegill and rainbow trout toxicity studies with nifluridide resulted in a half-life determination of 10 h at 13 degrees C and 2.5 h at 20 degrees C with nearly quantitative conversion to EL-919 within 96 h.
