Engineering Two-Dimensional Pd Nanoplates with Exposed Highly Active {100} Facets Toward Colorimetric Acid...

Area of Science:

• Materials Science
• Nanotechnology
• Biochemistry

Background:

• Nanomaterial properties like size, composition, and structure critically influence their enzyme-like activity.
• Optimizing structural parameters is essential for enhancing nanomaterial catalytic efficiency.

Purpose of the Study:

• To investigate the effect of crystal facets on the oxidase-like activity of palladium nanoplates.
• To develop an efficient nanozyme for colorimetric acid phosphatase (ACP) detection.
• To establish a sensitive and accurate assay for ACP in biological samples.

Main Methods:

• Synthesized two-dimensional palladium nanoplates enclosed by {100}-facets ([{100}PdSP@rGO]) and {111}-facets, as well as palladium nanocubes.
• Evaluated the intrinsic oxidase-like activities of these nanomaterials using the chromogenic reaction of 3,3',5,5'-tetramethylbenzidine.
• Utilized ascorbic acid 2-phosphate as a substrate for colorimetric ACP detection with the {100}PdSP@rGO nanozyme.

Main Results:

• {100}PdSP@rGO exhibited significantly enhanced oxidase-like activity compared to {111}-facets nanoplates and Pd nanocubes.
• Developed a colorimetric assay for ACP with a linear range of 0.01–6.0 mU/mL and a detection limit of 8.3 μU/mL.
• Successfully applied the assay to determine ACP levels in serum samples with high accuracy.

Conclusions:

• The exposed crystal facets and high specific surface area of nanomaterials can be finely tuned to control their enzyme-like activity.
• {100}-faceted palladium nanoplates represent a promising nanozyme platform for sensitive and accurate ACP detection.
• This approach offers a non-destructive method for ACP assay development, avoiding the use of hydrogen peroxide.