A spectrophotometric assay procedure is described for individually measuring theophylline-7-acetic acid and theophylline in 2.0 ml of serum. Absorbance is a linear function of concentration over a range of 0.5-40 mg/liter for theophylline-7-acetic acid and 0.5-40 mg/liter for theophylline. No endogenous or exogenous compounds were found that interfere with theophylline-7-acetic acid determinati...

Simple and sensitive spectrophotometric and radiochemical procedures are described for the assay of acetyl-CoA:arylamine N-acetyltransferase (NAT; EC 2.3.1.5), which catalyzes the reaction acetyl-CoA + arylamine----N-acetylated arylamine + CoASH. The methods are applicable to crude tissue homogenates and blood lysates. The spectrophotometric assay is characterized by two features: (i) NAT activ...

A spectrophotometric recycling assay for the quantitation of L-phenylalanine (and phenylpyruvate) has previously been reported (Cooper et al., Anal. Biochem. 183, 210-214, 1989). The procedure involves the coupling of bacterial phenylalanine dehydrogenase with rat kidney cytosolic glutamine transaminase K. The latter enzyme possesses high affinity for phenylpyruvate. Recycling results in a > or...

Background : We tested the in vitro activity of pleconaril and AG7088 against five numbered human rhinovirus (HRV) serotypes and 46 clinical HRV isolates of undefined serotype recovered from patients with common colds. Antiviral effect of pleconaril and AG7088 were assessed by cytophathic effect (CPE) inhibition assays in Ohio HeLaI cells using microscopic and spectrophotometric methods. Both c...

Inhibition of the mammalian soluble epoxide hydrolase (sEH) is a promising new therapy in the treatment of disorders resulting from hypertension and vascular inflammation. A spectrophotometric assay (4-nitrophenyl-trans-2,3-epoxy-3-phenylpropyl carbonate, NEPC) is currently used to screen libraries of chemicals; however this assay lacks the required sensitivity to differentiate the most potent ...

A spectrophotometric method of assay of mefenamic acid in tablets involving, dissolving the tablet powder in 1,4-dioxane and measuring the absorbance at 353.2 nm. The concentration of mefenamic acid is determined using the previously prepared calibration curve using standard solution of mefenamic acid in dioxane. The method was tested by assay of six different commercial tablets containing mefe...