title: Simultaneous extraction of beta-endorphin and leu- and met-enkephalins from human and rat plasma.
abstract: A simple, rapid and reliable procedure is described to simultaneously concentrate and purify beta-endorphin, leu- and met-enkephalins from small volumes of human and rat plasma before radioimmunoassay is performed. It uses C18 Sep-Pak reverse phase cartridges. The effectiveness of different protease inhibitors in preventing degradation of opiates by plasma and different solvent systems for eluting opiates is also evaluated.
authors: CNL, USDA, Beltsville, Maryland.
authors: S J
authors: SJ
authors: Bhathena
authors: P M
authors: PM
authors: Smith
authors: B W
authors: BW
authors: Kennedy
authors: N R
authors: NR
authors: Voyles
authors: L
authors: L
authors: Recant
mesh_terms: D000818:Animals; D002852:Chromatography, Ion Exchange; D004723:Endorphins / Q000097:blood* / Q000302:isolation & purification; D004743:Enkephalin, Leucine / Q000097:blood* / Q000302:isolation & purification; D004744:Enkephalin, Methionine / Q000097:blood* / Q000302:isolation & purification; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011863:Radioimmunoassay / Q000379:methods; D051381:Rats; D012997:Solvents
chemical_list: D004723:Endorphins; D012997:Solvents; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine