Journal of the American Pharmaceutical Association (Scientific ed.)最新文献

The adsorption of sarin from n-heptane solutions by silica gels, alumina, bentonite, and certain carbonaceous adsorbents was studied. The results obtained have been interpreted according to the Langmuir adsorption isotherm. Of the various adsorbents tested, those of a silicaceous nature were found to be superior, exhibiting very strong adsorptive tendencies toward the fluorophosphate ester. A linear relationship was found to exist between the limiting adsorptive capacity and the specific surface area of the adsorbents. The average area occupied by a sarin molecule, furthermore, was found to be approximately 80 Ų, irrespective of the adsorbent, a value in reasonable agreement with that suggested by a molecular model. Both of these relationships indicate that sarin is adsorbed primarily as a unimolecular layer.

Six theophylline preparations have been tested for their absorption from the gastrointestinal tracts of animals as reflected by blood theophylline levels. These values were obtained first from the stomach, and then from the remainder of the gastrointestinal tract. The results showed satisfactory absorption with all medications, and the wide variation inherent in oral preparations. No real superiority was evident in the six preparations when the available theophylline was the same in each drug.

Certain diquaternarized piperidine derivatives and several bis-tertiary amines were evaluated in the anesthetized rat and dog. The most active hypotensive agents were: 3-mor-pholinopropyl N-methylpipecolinate di-methiodide (JB-643), 2-morpholinoethyl N-methylpipecolinate dimethobromide (JB-654), and beta (3-diethylamino-1-propynyl)-N-methylpiperidine dimethobromide (JB-579). The compounds JB-643 and JB-654, administered orally to unanesthetized dogs, produced marked hypotensive responses persisting for more than eleven hours.

The basis and procedure for a culture method employing membrane filters to test freshly prepared parenteral solutions for pyrogenic capacity is presented. Under the limiting conditions described, solutions which yielded counts of less than 10,000 per L. were found to be nonpyrogenic by rabbit test. On the basis of laboratory and field trial, it is concluded that the bacteriological assay for the purpose described is as specific and sensitive as the rabbit assay for pyrogenicity.

The degradation of glucose in acid solution was carried out at various temperatures. The first-order rate constants for the decomposition reaction, obtained from the initial rate of formation of 5-hydroxymethylfurfural (5HMF), were consistently higher than those calculated from glucose depletion measurements over long periods of time at temperatures above 100°. At 100° the rate of formation of 5-HMF increased with time for the early portion of the break-down. The rate constant did not coincide with the Arrhenius plot for higher temperatures. This indicates the possibility of a change of mechanism at lower temperatures. The rate data was fitted to kinetic expressions for first-order consecutive reactions. Agreement between calculated and experimental values indicates that the reaction proceeds by the step-wise mechanism. Data obtained from degradation in varying acid concentrations show that the rate constant does not vary linearly with normality. Decomposition in dioxane-water mixtures indicates that the logarithm of the rate constant varies linearly with the reciprocal of the dielectric constant.

A system is described for the quantitative measurement of the contractions of the electrically driven rat ventricle strip. The apparatus includes the components of the transducer-amplifier-recording system as well as a simplified muscle-holder and electrode assembly. As normally employed, the system accurately measures semi-isometric (>0.025 mm. displacement) muscle contractions at a stimulus frequency of four per second. It may also be employed at other frequencies and for moderate isotonic contractions as well as for gas displacement.