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Determination of the biomarker L-tryptophan level in diabetic and normal human serum based on an electrochemical sensing method using reduced graphene oxide/gold nanoparticles/18-crown-6

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Abstract

A novel nanocomposite-modified electrode based on reduced graphene oxide (rGO) decorated with 18-crown-6 (Cr.6) and gold nanoparticles (GNPs) on the surface of a glassy carbon electrode (GCE) was successfully fabricated to investigate the electrochemical sensing of the biomarker L-tryptophan (L-Trp) in the presence of dopamine (DA), ascorbic acid (AA), urea, and glucose. The rGO-GNPs-Cr.6/GCE displayed high electrochemical catalytic activity for L-Trp determination using square-wave voltammetry (SWV). The electrochemical behavior of L-Trp at the rGO-GNPs-Cr.6/GCE displayed higher oxidation current and potential (oxidation peak current of 40 μA at 0.85 V) than rGO-GNPs/GCE, Cr.6/GCE, GNPs/GCE, rGO/GCE, and bare GCE. The SWV demonstrated a linear range of L-Trp concentration from 0.1 to 2.5 μM. A low limit of detection (LOD) was found for L-Trp, with LOD of about 0.48 μM and 0.61 μM in diabetic and normal serum, respectively. The fabricated sensor demonstrated high selectivity and sensitivity, and good stability and reproducibility for L-Trp sensing. Finally, the nanocomposite (rGO-GNPs-Cr.6)-modified GCE was applied for the determination of L-Trp in normal and diabetic human serum samples, and displayed excellent LOD and recoveries higher than 91.8%.

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Acknowledgments

The authors would like to express special thanks to Elham Honarvarfard and Hassan Maleki for their valuable insight.

Funding

This study was financially supported by the Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences (Grant No. 1396-01-100-2249).

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Authors and Affiliations

  1. Biosensor Research Center, Endocrinology & Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, 1411713137, Iran

    Kamyar Khoshnevisan & Mohammad Reza Khorramizadeh

  2. Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, 1411713137, Iran

    Kamyar Khoshnevisan, Sayed Mahmoud Sajjadi-Jazi, Mahsa Sadeghi Afjeh, Bagher Larijani & Mohammad Reza Khorramizadeh

  3. School of Chemistry, College of Science, University of Tehran, Tehran, 1417466191, Iran

    Farzad Torabi & Farnoush Faridbod

  4. Department of Medical Nanotechnology, Applied Biophotonics Research Center, Science and Research Branch, Islamic Azad University, Tehran, 1477893855, Iran

    Hadi Baharifar

  5. Cell Therapy and Regenerative Medicine Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, 1411713137, Iran

    Sayed Mahmoud Sajjadi-Jazi

  6. Center of Excellence in Electrochemistry, School of Chemistry, College of Science, University of Tehran, Tehran, 1417466191, Iran

    Farnoush Faridbod

  7. Zebrafish Core Facility, Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran, 1411713137, Iran

    Mohammad Reza Khorramizadeh

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  1. Kamyar Khoshnevisan
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Khoshnevisan, K., Torabi, F., Baharifar, H. et al. Determination of the biomarker L-tryptophan level in diabetic and normal human serum based on an electrochemical sensing method using reduced graphene oxide/gold nanoparticles/18-crown-6. Anal Bioanal Chem 412, 3615–3627 (2020). https://doi.org/10.1007/s00216-020-02598-5

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