title: Bi-enzyme L-arginine-selective amperometric biosensor based on ammonium-sensing polyaniline-modified electrode.
abstract: A novel L-arginine-selective amperometric bi-enzyme biosensor based on recombinant human arginase I isolated from the gene-engineered strain of methylotrophic yeast Hansenula polymorpha and commercial urease is described. The biosensing layer was placed onto a polyaniline-Nafion composite platinum electrode and covered with a calcium alginate gel. The developed sensor revealed a good selectivity to L-arginine. The sensitivity of the biosensor was 110 ± 1.3 nA/(mM mm(2)) with the apparent Michaelis-Menten constant (K(M)(app)) derived from an L-arginine (L-Arg) calibration curve of 1.27 ± 0.29 mM. A linear concentration range was observed from 0.07 to 0.6mM, a limit of detection being 0.038 mM and a response time - 10s. The developed biosensor demonstrated good storage stability. A laboratory prototype of the proposed amperometric biosensor was applied to the samples of three commercial pharmaceuticals ("Tivortin", "Cytrarginine", "Aminoplazmal 10% E") for L-Arg testing. The obtained L-Arg-content values correlated well with those declared by producers.
authors.affiliation: Ivan Franko National University of Lviv, Kyryla & Mefodia 6/8, 79005 Lviv, Ukraine.
authors.forename: Nataliya
authors.initials: N
authors.lastname: Stasyuk
authors.forename: Oleh
authors.initials: O
authors.lastname: Smutok
authors.forename: Galina
authors.initials: G
authors.lastname: Gayda
authors.forename: Bohdan
authors.initials: B
authors.lastname: Vus
authors.forename: Yevgen
authors.initials: Y
authors.lastname: Koval'chuk
authors.forename: Mykhailo
authors.initials: M
authors.lastname: Gonchar
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D001119:Arginase / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001120:Arginine / Q000032:analysis* / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D010843:Pichia / Q000235:genetics; D000644:Quaternary Ammonium Compounds / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D012680:Sensitivity and Specificity; D014510:Urease / Q000378:metabolism*
chemical_list: D000814:Aniline Compounds; D004800:Enzymes, Immobilized; D000644:Quaternary Ammonium Compounds; D011994:Recombinant Proteins; C416807:polyaniline; D001120:Arginine; D014510:Urease; C574619:ARG1 protein, human; D001119:Arginase