title: Flow cytometric ion detection with plasticized poly(vinyl chloride) microspheres containing selective lonophores.
abstract: The use of flow cytometry as a rapid, high-throughput diagnostic tool for the analysis of ions is described. Monodisperse, uniform microspheres, which obey bulk optode theory and are governed by bulk extraction processes rather than surface phenomena, were prepared under mild, nonreactive conditions using a sonic stream particle casting apparatus. As an initial example demonstrating the utility of this approach, microspheres that contained a H+-selective fluorescent chromoionophore (ETH 5294), a cation-exchanger (NaTFPB), and either a highly sodium-selective (sodium ionophore X) or a potassium-selective ionophore (BME-44) were prepared. Separate solution analysis of sodium- and potassium-selective microspheres resulted in the generation of functional response curves using peak channel fluorescence intensities. The selectivity observed for both types of particles is sufficient for the clinical determination of Na+ and K+. Furthermore, sodium- and potassium-selective microspheres were analyzed in parallel using sodium sample solutions, resulting in the successful determination of sodium ion concentrations and providing important information about the selectivity of the potassium-selective sensors over sodium. This work demonstrates the potential applicability of flow cytometry as a means for developing multiplexed, rapid, high-throughput analyses for clinically relevant ions.
authors.affiliation: Department of Chemistry, Auburn University, Alabama 36849, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Retter
authors.forename: Shane
authors.initials: S
authors.lastname: Peper
authors.forename: Michael
authors.initials: M
authors.lastname: Bell
authors.forename: Ioannis
authors.initials: I
authors.lastname: Tsagkatakis
authors.forename: Eric
authors.initials: E
authors.lastname: Bakker
mesh_terms: D005434:Flow Cytometry / Q000379:methods*; D007202:Indicators and Reagents; D007476:Ionophores / Q000032:analysis; D008863:Microspheres; D010316:Particle Size; D010968:Plasticizers; D011143:Polyvinyl Chloride; D012964:Sodium / Q000032:analysis; D013050:Spectrometry, Fluorescence
chemical_list: D007202:Indicators and Reagents; D007476:Ionophores; D010968:Plasticizers; D011143:Polyvinyl Chloride; D012964:Sodium