title: Potassium ion-selective optodes based on the calix[6]arene hexaester and application in human serum assay.
abstract: Plasticized PVC membranes incorporating the hexaester of calix[6]arene, potassium tetrakis(4-chlorophenyl) borate and a neutral H+-selective chromo-ionophore (ETH 5294) have been used as reversible sensing devices for optical determination of potassium ion in pH-buffer solutions. At pH 9.0, the absorbance response of the optode shows a good correlation with the theoretically derived formula in the range from 1 x 10(-6) to 1 x 10(-2) mol l(-1) potassium ion. Typical response times (t95) in the samples are 3 min, the relative standard deviation for repeated measurements being within 0.5%. The selectivity of this potassium-selective membrane allows its application for the reversible optical detection of potassium concentration in human serum samples.
authors.affiliation: Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Kowloon, Hong Kong.
authors.forename: W H
authors.initials: WH
authors.lastname: Chan
authors.forename: A W
authors.initials: AW
authors.lastname: Lee
authors.forename: D W
authors.initials: DW
authors.lastname: Kwong
authors.forename: W L
authors.initials: WL
authors.lastname: Tam
authors.forename: K M
authors.initials: KM
authors.lastname: Wang
mesh_terms: D002021:Buffers; D002414:Cations, Monovalent; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D055095:Optics and Photonics; D011143:Polyvinyl Chloride; D011188:Potassium / Q000097:blood*; D015203:Reproducibility of Results
chemical_list: D002021:Buffers; D002414:Cations, Monovalent; D008567:Membranes, Artificial; D011143:Polyvinyl Chloride; D011188:Potassium