title: The effect of soybean oil refuse powder used as vehicle on the absorption of oxolinic acid in chickens under fasting and nonfasting conditions and the correlation with in vitro dissolution.
abstract: The effect of soybean oil refuse powder (SOR) when used as a vehicle on the absorption of oxolinic acid (OXA) powder in chicken, the dissolution profile of OXA and the correlation between in vivo and in vitro study were examined. To examine in vivo bioavailability, chickens fed or fasted were studied using a 2 x 2 crossover design. The OXA was administered OXA or OXA-SOR (1 : 9) mixture 20 mg OXA/kg. In vitro dissolution rates for OXA and OXA-SOR were measured using the paddle (PD) and the rotatory dialysis cell dissolution (PTSW) methods. Maximum plasma concentration (Cmax) and area under the curve (AUC) were significantly increased by the addition of SOR to OXA. Differences between OXA and OXA-SOR were more remarkable under fasted as compared with fed condition. In vitro dissolution rates of OXA-SOR pH 1.2, 6.5 and 7.2 as determined by the PD and the PTSW methods were increased in the presence of SOR vehicle. Differences between OXA and OXA-SOR in vitro dissolution rates were greater than in vivo bioavailability. Correlation between in vitro release (%) and in vivo absorption (%) showed good linearity (gamma=0.8805-0.9999).
authors.affiliation: National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokura 1-15-1, Kokubunji-shi 185-8511, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hamamoto
authors.forename: R
authors.initials: R
authors.lastname: Koike
authors.forename: Y
authors.initials: Y
authors.lastname: Machida
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000890:Anti-Infective Agents / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002645:Chickens; D005215:Fasting / Q000378:metabolism; D005260:Female; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D007408:Intestinal Absorption / Q000187:drug effects*; D008657:Metabolic Clearance Rate; D010093:Oxolinic Acid / Q000097:blood / Q000493:pharmacokinetics*; D011208:Powders; D013024:Soybean Oil / Q000494:pharmacology*; D013810:Therapeutic Equivalency
chemical_list: D000890:Anti-Infective Agents; D011208:Powders; D013024:Soybean Oil; D010093:Oxolinic Acid