Graphene-Gold Nanoparticles Nanozyme-Based Electrochemical Sensor with Enhanced Laccase-Like Activity for Determination of Phenolic Substrates
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, cilt.168, sa.6, 2021 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 168 Sayı: 6
- Basım Tarihi: 2021
- Doi Numarası: 10.1149/1945-7111/ac0c32
- Dergi Adı: JOURNAL OF THE ELECTROCHEMICAL SOCIETY
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Analytical Abstracts, Applied Science & Technology Source, Chemical Abstracts Core, Chimica, Compendex, Computer & Applied Sciences, INSPEC
- Ankara Üniversitesi Adresli: Evet
Özet
Graphene decorated with gold nanoparticles (Au-rGO) was obtained in a single-step synthesis by exfoliating graphite rods via pulses of current. The morphological and structural features of Au-rGO were explored by TEM/SEM/EDX and XRD techniques. TEM images reveal the co-existence of thin and transparent sections corresponding to few-layer graphene along with darker regions corresponding to multi-layer graphene. Such a mixture was further confirmed by XRD examination of the sample. Au-rGO was next deposited on top of a screen-printed electrode (Au-rGO/SPE), and its electro-catalytic activity toward catechol oxidation was compared with that of a laccase-modified electrode (Lac/SPE). For Au-rGO/SPE, the dependence between the peak current and catechol concentration was linear within a wide range (1.0 x 10(-9)-1.0 x 10(-3) M) with a sensitivity of 0.048 A/M. The limit of quantification was very low, 1.0 x 10(-9) M, and the limit of detection was calculated to be 3.3 x 10(-10) M (S/N = 3). In contrast, the Lac/SPE has three times lower sensitivity toward catechol (0.016 A M-1) and a higher LOD (3.3 x 10(-6) M). The Au-rGO/SPE was tested for the detection of catechol in tap and mineral water samples with recovery percentages from 90.9% to 100.1%. (C) 2021 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.