Disposable Electrochemical Sensor Using Graphene Oxide–Chitosan Modified Carbon-Based Electrodes for the Detection of Tyrosine

Despite the many recent advances in disposable and wearable sensing technologies for point of care testing (POCT), few affordable, flexible, sensors are available detection tyrosine (Tyr), a valuable biomarker metabolic neurodegenerative diseases. In this regard, screen-printed electrodes on flexible substrates attractive. However, current approaches Tyr use rigid ceramic substrates, expensive metal nanoparticle conductive inks stiff or oxide-based sensitive materials, that not suitable single-use POCT devices. To address these challenges, work presents electrochemical sensor using graphene oxide – chitosan (GO-CS) modified carbon-based Tyr. The affordable easy to fabricate consists three-carbon electrode system screen printed low-cost polyvinyl chloride (PVC) substrate. GO CS were chosen as nanocomposite due their natural abundance excellent properties. Quantitative determination DPV revealed linear proportional response between 1 $100~\mu \text{M}$ , with correlation coefficient 0.9993. GO-CS-screen-printed carbon (SPCS) also offers range limit notation="LaTeX">$5.86~\mu sensitivity ( notation="LaTeX">$0.0846\,\,\mu \text{A}\,\,\mu \text{M}^{-1}$ ) repeatability (RSD =4.02%). GO-CS-SPCS thereby provides promising platform active elements single-use, disposable, devices early diagnosis monitoring diseases nutritional management.