All-solid-state K⁺ sensing array based on Au@polystyrene nanocomposites.

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biosensing Technology

Background:

• All-solid-state ion-selective electrodes (ASS-ISEs) offer miniaturization for home sensing but face accuracy and stability issues.
• Non-specific adsorption and complex preparation hinder ASS-ISE performance.
• Previous attempts using PS-Au nanocomposites had uniformity challenges.

Purpose of the Study:

• To develop a more stable and accurate ASS-ISE for potassium (K+) detection.
• To simplify electrode preparation and improve batch-to-batch consistency.
• To validate the sensor's performance for home health monitoring applications.

Main Methods:

• Preparation of Au@PS nanocomposites as sensor materials.
• Fabrication of a K+ sensing array by drop-casting Au@PS onto screen-printed carbon electrodes (SPCEs).
• Testing the sensor's performance, including near-Nernstian behavior, reproducibility, and comparison with ICP-AES for urine samples.

Main Results:

• The K+ Au@PS sensing array demonstrated near-Nernstian behavior over a wide concentration range (1.0 × 10-3 M to 0.3 M).
• The sensor exhibited good reproducibility in real sample testing.
• Detection results for K+ in human urine closely matched those obtained by ICP-AES.

Conclusions:

• Au@PS nanocomposites provide a simplified and more uniform material for ASS-ISE fabrication.
• The developed K+-ASS-ISE is suitable for accurate and reliable home health monitoring of potassium levels.
• This technology advances the potential for accessible, point-of-care diagnostics.