Exploring Zr-Based Metal-Organic Frameworks as Smart Electrochromic Sensors by Coordination-Driven Surface...

Area of Science:

• Materials Science
• Electrochemistry
• Biosensing

Background:

• Electrochromic metal-organic frameworks (MOFs) show promise but face challenges in water stability, synthesis, and signal transduction for sensing.
• Existing MOF applications are limited by difficulties in integrating specific recognition events with responsive material properties.

Purpose of the Study:

• To develop stable and functional electrochromic MOFs for advanced sensing applications.
• To establish a coordination-driven surface engineering strategy for creating smart electrochromic sensors.
• To demonstrate label-free and specific detection of biomolecules using these novel MOF-based sensors.

Main Methods:

• Post-synthetic modification of a Zr-based MOF with a viologen-like moiety to achieve electrochromic activity.
• Coordination-driven surface engineering by tethering phosphate-containing biomolecules to MOF Zr nodes.
• Fabrication of MOF-coated conductive films for electrochemical and colorimetric detection.
• Functionalization with aptamers for specific target recognition.

Main Results:

• A Zr-based MOF exhibiting electrochromic activity was successfully synthesized and functionalized.
• The coordination-driven strategy effectively tuned interface electron transfer for enhanced sensing.
• Label-free detection of phosphoproteins and specific aptamer-based detection of targets were achieved.
• Distinct color changes in the MOF sensors allowed for visual quantification of analytes.

Conclusions:

• This work presents the first MOF-based electrochromic sensors developed through an efficient surface engineering strategy.
• The developed MOF sensors combine electrochemical sensitivity with colorimetric visual detection.
• The strategy demonstrates broad applicability for developing electrochromic MOF sensors for diverse sensing tasks.