title: The in vivo distribution of the 99mTc-labelled albumin and gelatin microspheres of a tuberculostatic agent, rifampicin.
abstract: The preparation of albumin and gelatin microspheres with a tuberculostatic agent, rifampicin, was studied, and its in vivo distribution was investigated by providing its accumulation in the target organ lungs. The purpose of the study is to improve the effectiveness by injecting the microspheres intravenously with much smaller doses than normally required with generalized systemic administration, whilst reducing the systemic side effects. The emulsion polymerization method is applied in microsphere preparation, and glutaraldehyde is employed for albumin and formaldehyde for gelatin microspheres as the cross-linking agents. Biodistribution was determined by intravenous administration of particles of 25 to 27 microns 99mTc-labelled microspheres to Swiss albino mice. The radioactivity of the lungs was compared with the radioactivity of the liver, spleen, kidney, stomach and heart at 10, 30 and 60 min, and 6 and 24 h post-injection. The percentage accumulated was higher in the lungs than in the other organs for both albumin and gelatin microspheres, whereas free rifampicin accumulated mainly in the liver. To support the data of the in vivo distribution studies, the microspheres were histopathologically investigated after the intravenous injection to Swiss albino mice. After the microscopic determination of the lungs and liver, the spherical microspheres were observed after 10,30 and 60 min, and 6 and 24 h post-injection.
authors.affiliation: Pharmaceutical Technology Department-Pharmacy Faculty, University of Hacettepe, Ankara Turkey.
authors.forename: E
authors.initials: E
authors.lastname: Işeri
authors.forename: M T
authors.initials: MT
authors.lastname: Ercan
authors.forename: H S
authors.initials: HS
authors.lastname: Kaş
authors.forename: A A
authors.initials: AA
authors.lastname: Hincal
mesh_terms: D000818:Animals; D005780:Gelatin; D006801:Humans; D051379:Mice; D008863:Microspheres; D012293:Rifampin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D013668:Technetium Tc 99m Aggregated Albumin; D014018:Tissue Distribution
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin; D005780:Gelatin; D012293:Rifampin