title: Simultaneous determination of L- and D-T4 using a sequential injection analysis/sensors system.
abstract: A sequential injection analysis system was selected for the simultaneous determination of L- and D-T4 in raw material and pharmaceutical products, because of the highest precision and accuracy, the lower consumption of sample and buffer, and the flexibility of selecting different buffers accordingly with the type of sensors utilized as detectors. An amperometric biosensor based on D-amino acid oxidase was used as detector for D-T4 and an immunosensor based on anti-L-T4 was used as detector for L-T4. The SIA/biosensors system can be used reliably on-line in synthesis process control, for the simultaneous assay of L- and D- T4 with a frequency of more than 30 samples per hour.
authors.affiliation: Laboratory of Electrochemistry and PATLAB Bucharest, National Institute of Research for Electrochemistry and Condensed Matter, 202 Splaiul Independentei Str., Bucharest, Romania. iustinavanstaden@yahoo.com
authors.forename: Raluca-Ioana Stefan
authors.initials: RI
authors.lastname: van Staden
authors.forename: Jacobus Frederick
authors.initials: JF
authors.lastname: van Staden
authors.forename: Hassan Y
authors.initials: HY
authors.lastname: Aboul-Enein
authors.forename: Ionel
authors.initials: I
authors.lastname: Balcu
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D017022:Flow Injection Analysis / Q000379:methods*; D007118:Immunoassay / Q000379:methods*; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D013237:Stereoisomerism; D013974:Thyroxine / Q000031:analogs & derivatives* / Q000032:analysis*
chemical_list: D004364:Pharmaceutical Preparations; D013974:Thyroxine