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Biomedical subjects

P Van Aerde

Publications and source records attributed to P Van Aerde.

5 recordsLinked to original sources
PubMed1993

Chemical and physicochemical characterization of petrolatums used in eye ointment formulations.

Petrolatums from different manufacturers were characterized by viscosity measurements, oil number and ratio of low to high mol. wt components (capillary gas chromatography). Viscosity measurements and oil numbers of original materials did not correlate with the viscosity of the processed material in eye ointments. The ratio of high carbon number components to the low carbon number components was a reliable predictor for the viscosity of the formulation.

Chemical Phenomena↗
PubMed1984

Polymorphic behaviour of chloroquine diphosphate.

The crystalline structure of two different batches of chloroquine diphosphate was studied. Differential thermal analysis showed the existence of two polymorphic modifications in one of the batches, whilst spectral analysis did not reveal any differences. This discrepancy is attributed to the fact that the second modification is formed during the transition phase when analysed by differential thermal analysis. This recrystallization process is initiated by the presence of seed material. The ratio of transition heat of both modifications is dependent on particle size and heating rate during analysis.

Chloroquine↗
PubMed1984

The rabbit as an experimental model for biopharmaceutical studies following rectal administration of theophylline.

In order to find a suitable animal model for biopharmaceutical studies after rectal application of theophylline, the pharmacokinetics of theophylline following the administration in rabbits of three different rectal preparations were examined and compared with those of the oral and i. v. route. No significant formulation related impact from the studied rectal dosage forms on the bioavailability of the drug was found. However, the unexpected rapid achievement of peak serum concentration after insertion of the suppository lacked any correlation with human experiments. It was concluded that the evaluation of rectal theophylline medication for man cannot directly be based on the data obtained from rabbits.

Administration, Oral↗
PubMed1981

Determination of plasma theophylline by straight-phase high-performance liquid chromatography: elimination of interfering caffeine metabolites.

Several authors have recently reported interference in theophylline analysis by paraxanthine (1,7-dimethylxanthine), an important metabolite of caffeine. A method for the determination of theophylline in plasma is described, eliminating caffeine and related compounds by means of straight-phase high-performance liquid chromatography. The resulting procedure is sufficiently rapid, accurate and sensitive to be applied in routine monitoring of therapeutic levels in patients as well as for pharmacokinetic purposes. Although only 0.1 ml of sample is required, concentrations as low as 0.2 mg/l can be measured with acceptable precision. A brief comparative evaluation of this procedure with a radioimmunoassay is made.

Beverages↗