1. Determination of epinephrine in human serum using a Pt electrode modified by polyaniline-poly(3-methylthiophene) -poly(3,3'-diaminobenzidine)
- Author
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Ulker, Emine and Kavanoz, Muammer
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Serum -- Analysis ,Polymers -- Usage -- Comparative analysis -- Chemical properties -- Research ,Epinephrine -- Comparative analysis -- Chemical properties -- Analysis ,Chemistry - Abstract
A Pt electrode modified by polyaniline-poly(3-methylthiophene)-poly(3,3'-diaminobenzidine) was used for amperometric determination of epinephrine in a solution of NaHS[O.sub.4]/[Na.sub.2]S[O.sub.4] (pH 2.0). For these studies, potentials between 0.40 and 0.50 V were applied, and the best response was obtained at 0.45 V. The limit of detection, limit of quantification, and the linear dynamic range were 1.23 x [10.sup.-4], 4.10 x [10.sup.-4], and 4.10 x [10.sup.-4] to 100.0 mmol [L.sup.-1], respectively. These results were compared with determinations using Pt electrodes that were coated and uncoated with homopolymers. To check the accuracy of the developed method and the matrices interference, determination of epinephrine was performed in human serum samples using this modified electrode. The epinephrine concentrations were adjusted to 1.0 and 5.0 mmol [L.sup.-1], and recovery values were calculated as 100.4% and 96.8%, respectively. It is significant that the determination of epinephrine was carried out at a lower potential (0.45 V) than the oxidation potential of epinephrine (0.65 V) without any matrix effect. Keywords: epinephrine, polyaniline, poly(3-methylthiophene), poly(3,3'-diaminobenzidine), amperometric determination. Nous avons utilise une electrode de platine modifiee par des polymeres constitues de polyaniline, de poly(3-methylthiophene) et de poly(3,3'-diaminobenzidine) pour effectuer le dosage amperometrique de l'epinephrine dans une solution de NaHS[O.sub.4] et de [Na.sub.2]S[O.sub.4] (pH 2,0). Aux fins d'etudes amperometriques, nous avons applique des potentiels allant de 0,40 a 0,50 V et avons obtenu la meilleure reponse a 0,45 V. Le seuil de detection, le seuil de quantification et le domaine de linearite ont ete respectivement de 1,23 x [10.sup.-4], 4,10 x [10.sup.-4] et de 4,10 x [10.sup.-4] a 100,0 mmol [L.sup.-1]. Nous avons compare ces resultats pour les electrodes de platine recouvertes d'homopolymeres et l'electrode nue. En vue de verifier l'exactitude de la methode mise au point et l'interference des supports, nous avons effectue le dosage de l'epinephrine dans des echantillons de serum humain a l'aide de cette electrode modifiee. Nous avons ajuste les concentrations d'epinephrine a 1,0 et 5,0 mmol [L.sup.-1], et avons calcule des valeurs du rendement de 100,4% et de 96,8%, respectivement. Il est important de noter que le dosage de l'epinephrine a ete effectue a potentiel inferieur (0,45 V) au potentiel d'oxydation de l'epinephrine (0,65 V), sans effet du support. [Traduit par la Redaction] Mots-cles: epinephrine, polyaniline, poly(3-methylthiophene), poly(3,3'-diaminobenzidine), dosage amperometrique., Introduction Catecholamines are water-soluble organic compounds that are produced in the body from tyrosine, and they are the main neurotransmitters that mediate central nervous system functions such as motor control, [...]
- Published
- 2015
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