Defective PdMo metallene with efficient catalase-like activity for sensitive immunoassay

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Nanozyme-based biosensors offer high potential for trace analyte detection.
• Rational design of high-performance nanozymes is critical for advanced immunoassays and point-of-care testing (POCT).
• Developing efficient nanozymes remains a significant challenge.

Purpose of the Study:

• To synthesize and characterize novel nanozyme materials for enhanced biosensing.
• To investigate the catalytic properties and mechanism of the synthesized nanozymes.
• To demonstrate the application of the nanozyme in a portable immunoassay sensor.

Main Methods:

• Synthesis of ultrathin palladium-molybdenum metallene nanosheets (d-PdMoene) with a high density of defects.
• Evaluation of catalase-like activity (CAT-like activity) through H2O2 decomposition.
• Theoretical calculations (e.g., DFT) to understand electronic structure and catalytic mechanisms.
• Development of a pressure-based immunoassay sensor for prostate-specific antigen (PSA).

Main Results:

• Successfully synthesized d-PdMoene with superior CAT-like activity.
• Theoretical calculations confirmed enhanced H2O2 adsorption and easier O2 release due to optimal electronic configuration and defect sites.
• The generated O2 produced measurable pressure changes, enabling portable detection.
• A PSA immunoassay sensor demonstrated high sensitivity and selectivity using d-PdMoene.

Conclusions:

• Defect-rich d-PdMoene exhibits excellent nanozyme activity for biosensing applications.
• The study provides a framework for designing high-performance nanozymes.
• This work paves the way for developing practical, portable POCT devices.