Flexible hydrogel sensor based on MoS₂ for highly selective dopamine detection against catecholamine...

Area of Science:

• Bioelectronics and Biosensing
• Materials Science
• Neuroscience

Background:

• Real-time dopamine monitoring is essential for neuroscience and diagnosing neurological disorders.
• Flexible and stretchable sensors offer advantages for bioelectronic applications due to conformal contact with biological tissues.
• Achieving high selectivity in sensors is challenging, particularly in complex physiological environments with interfering substances like epinephrine.

Purpose of the Study:

• To develop a highly stretchable and selective hydrogel-based sensor for real-time dopamine detection.
• To address the challenge of molecular discrimination against structurally similar catecholamines and common electroactive interferents.

Main Methods:

• Fabrication of a stretchable hydrogel sensor using acrylamide (AAM), carbon nanotubes (CNTs), and molybdenum disulfide (MoS₂).
• Integration of CNTs for enhanced electrical conductivity and MoS₂ for selective dopamine affinity.
• Evaluation of mechanical durability under strain and repeated stretch-release cycles, and assessment of sensing performance and selectivity.

Main Results:

• The AAM/CNT/MoS₂ hydrogel sensor demonstrated excellent mechanical durability, maintaining integrity under 50% strain and 15 stretch-release cycles.
• The sensor achieved a low detection limit of 6.1 nM for dopamine.
• High selectivity was observed, with reliable dopamine response maintained even in the presence of high concentrations of epinephrine and other interferents.

Conclusions:

• The developed hydrogel-based sensor offers a promising platform for soft, selective, and interference-resilient biosensing.
• This technology advances the development of wearable or implantable bioelectronics for dynamic neurochemical sensing.
• The sensor's ability to differentiate dopamine from epinephrine is a significant step towards accurate in-situ neurochemical monitoring.