Non-Equilibrium Potential Responses towards Neutral Orcinol Using All-Solid-State Potentiometric Sensors Integrated...

Area of Science:

• Electroanalytical Chemistry
• Materials Science
• Polymer Chemistry

Background:

• Molecularly imprinted polymers (MIPs) are recognized for their tailored molecular recognition capabilities.
• Solid-contact ion selective electrodes (SC-ISEs) offer advantages in simplified potentiometric measurements.
• Developing selective and sensitive sensors for non-dissociated organic compounds like orcinol remains a challenge.

Purpose of the Study:

• To synthesize and characterize novel MIP receptors for selective orcinol detection.
• To fabricate and evaluate SC-ISEs utilizing MIPs as the sensing layer.
• To investigate the performance of these sensors, including sensitivity, selectivity, and stability.

Main Methods:

• MIP receptors were synthesized using methacrylic acid (MAA) and acrylamide (AA) as monomers.
• Graphene (Gr) was employed as the solid contact material in the SC-ISEs.
• Sensor performance was evaluated using potentiometry, including detection limits, selectivity coefficients (via modified separate solution method), and potential stability (via constant-current chronopotentiometry).

Main Results:

• The developed SC-ISEs demonstrated enhanced detection sensitivity towards orcinol.
• Detection limits achieved were 1.7 × 10^-5 M for MIP/MAA and 3.3 × 10^-6 M for MIP/AA sensors.
• The sensors exhibited good selectivity for orcinol over common phenols and inorganic anions, with stable performance and no water film formation.

Conclusions:

• MIP receptors, particularly when combined with graphene as a solid contact, are effective for developing sensitive and selective SC-ISEs for orcinol.
• The proposed MIP/MAA incorporated ISE showed applicability in real-world samples, validated through recovery tests in a soil matrix.
• These findings highlight the potential of MIP-based SC-ISEs for the analysis of non-dissociated organic compounds.