A novel approach for the selective determination of tryptophan in blood serum in the presence of tyrosine based on the electrochemical reduction of oxidation product of tryptophan formed in situ on graphite electrode

Ozcan A., ŞAHİN Y.

BIOSENSORS & BIOELECTRONICS, cilt.31, sa.1, ss.26-31, 2012 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 31 Sayı: 1
  • Basım Tarihi: 2012
  • Doi Numarası: 10.1016/j.bios.2011.09.048
  • Dergi Adı: BIOSENSORS & BIOELECTRONICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.26-31
  • Anahtar Kelimeler: Tryptophan, Tyrosine, Blood serum, Electrochemically treated pencil graphite electrode, DPV, GLASSY-CARBON ELECTRODE, VOLTAMMETRIC DETERMINATION, URIC-ACID, DNA HYBRIDIZATION, PASTE ELECTRODE, BEHAVIOR
  • Yıldız Teknik Üniversitesi Adresli: Hayır

Özet

In this study, a novel method was proposed for the selective determination of tryptophan (TRP) in blood serum in the presence of tyrosine. This method is based on the electrochemical reduction of 2-amino-3-(5-oxo-3,5-dihydro-2H-indol-3-yl)-propionic acid (5-O-3,5DH-TRP) formed by the oxidation of TRP on the electrochemically treated pencil graphite (ETPG) electrode surface at a suitable potential value. The parameters affecting the TRP determination were deeply investigated. The optimal pH value was determined as 3. The highest reduction current intensity was obtained at the accumulation potential and time values of +0.95 V and 120 s, respectively. The reduction peak current values of 5-O-3,5DH-TRP versus TRP concentration at the ETPG electrode showed linearity in the range from 0.5 mu M to 50.0 mu M (R-2=0.9962) with a detection limit of 0.05 mu m (S/N = 3). The reduction peak intensity of 5-O-3,5DH-TRP on the ETPG electrode showed no significant change in the presence of different interfering substances. The analytical application of the proposed novel method was successfully tested by using human blood serum samples. (C) 2011 Elsevier B.V. All rights reserved.