Determination of Fluorinated Hydrocarbon Propellants in Blood of Dogs after Aerosol Administration

Fluorocarbon Aerosol Propellants XI: Pharmacokinetics of Dichlorodifluoromethane in dogs following single and multiple dosing

“…The terminal disposition half-lives reported here are much longer than those previously reported or speculated (7,8,10,(21)(22)(23).…”

“…Dosage F o r m and Route of Administration-The intravenous dosage form was selected to avoid the problems of biological availability in inhalation and oral administration (7)(8)(9)(10). This mode of administration would be equivalent to inhalation (3,4) if one considers that the intravenously administered fluorocarbon first passes through the lungs before being monitored in the blood.…”

“…l4C-Triamterene2 (0.92 mCi/mmole) was used as supplied. It was found to be chemically pure by descending paper chromatography in two solvent systems, I-butanol-acetic acid-water (41: 1) and 2-propanol-water-ammonia (140:5010), according to literature methods ( 4 4 . A 4 X 4 countercurrent distribution of l*C-triamterene between ethyl acetate (14 ml) and 0.1 M borate buffer a t pH 10.00 (7 ml) showed that it behaved like a single compound (6)(7)(8).…”

Fluorocarbon Aerosol Propellents X: Pharmacokinetics of Dichlorotetrafluoroethane in Dogs

“…Dosage Form and Route of Administration-An intravenous dosage form was chosen based on failures in the past to administer fluorocarbons quantitatively through the lungs (14,15) and to avoid problems of biological availability in oral administration (16). The merits for the selection of polyethylene glycol 400 as the infusion solvent were discussed earlier (11).…”

Fluorocarbon Aerosol Propellants III: Effect of Water Vapor on Sensitivity of Electron-Capture Detector during GC Analysis

“…The possible toxicity of the most commonly used aerosol propellants, fluorinated hydrocarbons, has been a subject of intensive research and controversy (4)(5)(6)(7)(8). Quantitation of these fluorocarbon propellants in biological samples could be most sensitively performed by the GC method using an electron-capture detector (8)(9)(10)(11)(12)(13). Although the technique of direct injection of blood samples onto GC columns has been used (9, 10,121, it can result in serious contamination of the column and therefore require frequent changes of the column.…”