title: Elution mode of Pneumocystis carinii cysts in gravitational field-flow fractionation.
abstract: The simplest field-flow fractionation technique, i.e. gravitational, was used in an attempt to purify a Pneumocystis carinii cyst suspension. This parasite is an opportunistic invader in immunocompromised patients, especially those suffering from AIDS. The cyst stage is spherical and 5 microns in diameter. Unexpected retention times, not systematically related to the size and the density of the parasite, were obtained under various experimental conditions. When silicone-coated walls were used, Pneumocystis carinii cysts were eluted in the void volume, whereas when uncoated walls were used with a sodium dodecyl sulphate-enriched carrier phase, retention was observed. These phenomena are probably related to the high degree of hydrophobicity of these micrometre-sized biological particles; this degree can be easily determined. The use of the gravitational field-flow fractionation technique can be of a great interest for the development of new methods for diagnostic purposes. Particle-wall interactions and their modifications due to the carrier phase or to the wall treatment can be employed in the search for new bronchoalveolar lavage solutions.
authors.affiliation: Laboratoire de Chimie Analytique et d'Electrochimie Organique, Université Paris-Sud, Châtenay-Malabry, France.
authors.forename: C
authors.initials: C
authors.lastname: Bories
authors.forename: P J
authors.initials: PJ
authors.lastname: Cardot
authors.forename: V
authors.initials: V
authors.lastname: Abramowski
authors.forename: C
authors.initials: C
authors.lastname: Poüs
authors.forename: A
authors.initials: A
authors.lastname: Merino-Dugay
authors.forename: B
authors.initials: B
authors.lastname: Baron
authors.forename: G
authors.initials: G
authors.lastname: Mougeot
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D002498:Centrifugation; D005591:Chemical Fractionation / Q000379:methods*; D003560:Cysts / Q000382:microbiology* / Q000473:pathology; D005260:Female; D006112:Gravitation; D006801:Humans; D008171:Lung Diseases / Q000382:microbiology; D011010:Pneumocystis / Q000302:isolation & purification*; D011020:Pneumonia, Pneumocystis / Q000473:pathology; D011650:Pulmonary Alveoli / Q000382:microbiology; D051381:Rats; D017208:Rats, Wistar