New sensitive bioassay for sulbactam in bovine tissues.

A quantitative cylinder plate bioassay for sulbactam has been developed which can detect concentrations as low as 0.01 microgram/g in bovine muscle, fat, kidney, and liver tissues. This procedure may also be applicable to human tissues and fluids.

The parenteral kinetics of ampicillin/sulbactam in man.

The kinetics of co-administered ampicillin plus sulbactam were examined at doses being used in clinical trials of this combination of a beta-lactam antibiotic (ampicillin) and a beta-lactamase inhibitor (sulbactam). Following 15-min infusion of 2 g ampicillin plus 1 g sulbactam, peak serum concentrations of 120 micrograms/ml ampicillin and 60 micrograms/ml sulbactam were observed. The half-life was approximately one hour for both drugs.

High-performance liquid chromatographic determination of cefoperazone in human serum and urine.

A gradient high-performance liquid chromatographic (HPLC) procedure has been developed for the determination of microgram amounts of cefoperazone in human serum and urine. The method employs a muBondapak C18 column and gradient elution with two mobile phases. Excellent separation of the drug from potential degradation products as well as from representative penicillins (sodium ampicillin, sodium methicillin, potassium penicillin G) and aminoglycosides (tobramycin, gentamicin, kanamycin) has been demonstrated.

Pharmacokinetics of sulbactam in humans.

Sulbactam, a new beta-lactamase inhibitor, has pharmacokinetic characteristics in humans similar to those of ampicillin and amoxicillin. Its half-life in humans is approximately 1 h. In a two-compartment pharmacokinetic model, the apparent volume of distribution for the central compartment is approximately 12 liters, and half of the dose is found in the central compartment in the postdistributive phase.

Turbidimetric bioassay for carbenicillin.

A quantitative turbidimetric bioassay has been developed for carbenicillin with the use of a strain of Escherichia coli. The assay is relatively specific for carbenicillin and is not affected by 10% (wt/wt) benzylpenicillin. It has been demonstrated to be more precise than the plate diffusion assay.