title: A novel potentiometric biosensor for determination of L-lysine in commercial pharmaceutical L-lysine tablet and capsule.
abstract: The construction of an L-lysine biosensor on ammonium-selective poly(vinylchloride) (PVC) membrane electrode is described in this study. The construction procedure occurs in two stages: (I) the preparation of ammonium-selective poly(vinylchloride) (PVC) membrane electrode and (II) the chemical immobilization of lysine oxidase on this ammonium-selective electrode by using glutaraldehyde. The ammonium ions produced after enzymatic reaction were determined potentiometrically. The sensitivity of the lysine biosensor against ammonium ions and lysine were studied. The response time, linear working range, reproducibility and life time of the biosensor were also determined. The interfering effect of other amino acids on the biosensor performance was also studied and potentiometric selectivity coefficients were calculated. Although the biosensor responded mainly against tyrosine, a lot of amino acids and ascorbic acid that can be present in some real samples did not show any important interference. Additionally, lysine assay in commercial pharmaceutical lysine tablets and capsules was also successfully carried out. The results were in good agreement with previously reported values.
authors.affiliation: a Deva Holding, Halkalı Merkez Mahallesi, Küçükçekmece , Istanbul , Turkey.
authors.forename: Saniye
authors.initials: S
authors.lastname: Yarar
authors.affiliation: b Department of Chemistry , Yildiz Technical University , Esenler, Istanbul , Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Karakuş
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis; D001205:Ascorbic Acid / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002021:Buffers; D002214:Capsules; D006863:Hydrogen-Ion Concentration; D008239:Lysine / Q000032:analysis*; D011199:Potentiometry; D015203:Reproducibility of Results; D013607:Tablets; D013696:Temperature; D013997:Time Factors
chemical_list: D064751:Ammonium Compounds; D002021:Buffers; D002214:Capsules; D013607:Tablets; D008239:Lysine; D001205:Ascorbic Acid
keywords: enzyme electrode; lysine biosensor; lysine determination; lysine oxidase; potentiometric