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Biomedical subjects

L O Wilken

Publications and source records attributed to L O Wilken.

13 recordsLinked to original sources

Liquid chromatographic determination of the pH-dependent degradation of eseroline--hydrolysis product of physostigmine.

The stability of eseroline, the hydrolysis product of physostigmine under aerobic conditions, was studied by liquid chromatography. A reversed-phase, ion-pair technique was used to separate eseroline from its degradation products. The degradation of eseroline in phosphate buffer solutions of pH 6.91, 7.40, 7.98, 8.41 and 8.94 appears to follow first-order kinetics; the rate constant increased with an increase in pH. The degradation appears to follow specific base catalysis.

Journal Article↗

Effects of gentamicin solution and cream on the healing of open wounds.

When 0.1% gentamicin solution was applied to full-thickness skin wounds of dogs, the wounds became smaller by contraction during the first 7 days and continued to contract over the next 14 days. Wounds treated with 0.1% gentamicin cream enlarged during the first 7 days, followed by wound contraction over the next 14 days. The wounds treated with gentamicin solution also had more epithelialization at 7 days than did the cream-treated wounds; however, epithelialization of the 2 types of wounds was similar at 14 and at 21 days. Gentamicin solution and cream were effective in controlling bacterial growth on wounds when compared with the bacterial growth on the control wounds (not treated with antibiotics).

Administration, Topical↗

New in vitro dissolution test apparatus.

A new in vitro dissolution test apparatus was designed and evaluated. Compressed tablets of drugs representing different solubility characteristics were tested at various air pressures and compared to dissolution patterns of similar tablets by the Levy beaker and USP methods. Air pressure of 46 mm generally was suitable for determining the dissolution rates of tablets. This new dissolution tester possibly can be useful in determining drug release from solid dosage forms and correlating it with in vivo bioavailability because dissolution rate can be controlled easily with the adjustment of air pressure without complicated changes in the apparatus, there is no excessive settling of particles, and complete drug dissolution can be achieved with no clogging of the screen.

Aspirin↗

Application of gluconolactone in direct tablet compression.

Gluconolactone was evaluated as an excipient for tablets prepared by direct compression using various drugs known to be difficult to compress. The physical properties of the tablets were evaluated after compression and after storage and were satisfactory. Comparative studies were conducted between gluconolactone and anhydrous lactose, a common direct compression diluent, for development of static charges during blending, flow, drug distribution, drug stratification, color distribution, compressibility, and preservation against mold growth. Gluconolactone possesses those properties necessary to produce high quality tablets by the direct compression process. Separate powdered mixtures of aspirin USP with gluconolactone, anhydrous lactose, spray-dried lactose, mannitol, and sorbitol were stored at various humidities and temperatures for specified periods and tested for the integrity of aspirin. Gluconolactone contributed least to the degradation of the drug as compared to other excipients studied. A preliminary in vivo study also was conducted on the bioavailability of aspirin from separate and similar mixtures with gluconolactone, anhydrous lactose, and starch. Gluconolactone did not show any inhibitory effect on aspirin absorption.

Animals↗