In Vivo Dopamine Biosensor Based on Copper(I) Sulfide Functionalized Reduced Graphene Oxide Decorated Microelectrodes

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Neuroscience

Background:

• Dopamine is a crucial neurotransmitter involved in various physiological processes.
• Sensitive and selective detection of dopamine is essential for understanding neurological functions and disorders.
• Existing biosensors often face challenges with sensitivity, selectivity, and in vivo applicability.

Purpose of the Study:

• To develop a novel dopamine biosensor with enhanced sensitivity and selectivity.
• To investigate the potential of copper(I) sulfide functionalized reduced graphene oxide nanocomposites for dopamine detection.
• To demonstrate the in vivo monitoring capability of the developed biosensor in Drosophila brains.

Main Methods:

• Fabrication of carbon fiber microelectrodes (CFMEs) modified with copper(I) sulfide/reduced graphene oxide (Cu2S/RGO) nanocomposites.
• Characterization of the modified electrodes using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV).
• Electrochemical detection of dopamine and evaluation of sensor performance metrics including detection limit, linear range, selectivity, and reproducibility.

Main Results:

• The Cu2S/RGO-CFMEs exhibited excellent catalytic activity and high selectivity towards dopamine.
• The developed dopamine biosensor demonstrated a low detection limit (24 nM) and a wide linear range (0.1–20 μM).
• The biosensor successfully performed in vivo monitoring of dopamine in Drosophila brains with high sensitivity and stability, showing no interference from other electroactive species.

Conclusions:

• The novel Cu2S/RGO-CFMEs provide a sensitive, selective, and reproducible platform for dopamine detection.
• The developed biosensor is suitable for real-time in vivo monitoring of neurotransmitters in complex biological samples.
• This research highlights the potential of nanomaterial-modified electrodes for advancing neuroscience research and diagnostics.