Tyrosine-Capped Pt Nanozyme Functionalized with cDNA: An Innovative Sensor Designed for One-Step Detection of the...

Area of Science:

• Biomaterials
• Nanotechnology
• Analytical Chemistry

Background:

• Platinum nanozymes (Pt-NZs) exhibit promising catalytic properties for biosensing.
• Tyrosine capping enhances the stability and catalytic efficiency of Pt-NZs.
• MicroRNA-21 (miRNA-21) is a significant biomarker for various cancers.

Purpose of the Study:

• To synthesize and characterize tyrosine-capped platinum nanozymes (Pt-Tyr NZ).
• To develop a novel, sensitive, and specific biosensing method for miRNA-21 detection.
• To evaluate the performance of the developed biosensor in biological samples.

Main Methods:

• Synthesis of Pt-Tyr NZ with demonstrated peroxidase and oxidase activities.
• Reversible conjugation of Pt-Tyr NZ with complementary DNA (cDNA) for miRNA-21 recognition.
• Spectrophotometric detection based on the change in catalytic activity upon miRNA-21 hybridization.

Main Results:

• Pt-Tyr NZ exhibited superior catalytic activity and substrate affinity compared to horseradish peroxidase (HRP).
• The biosensing method showed high reproducibility (RSD = 1.26%), repeatability (RSD = 0.83%), and accuracy (109.7% recovery in serum).
• A linear dynamic range of 37.1–185 nM with a low limit of detection (11.1 nM) for miRNA-21 was achieved.

Conclusions:

• Pt-Tyr NZ offers a highly efficient platform for biosensing applications.
• The developed one-step spectrophotometric method provides a sensitive and reliable approach for miRNA-21 detection.
• This biosensor demonstrates potential for early cancer diagnosis using miRNA biomarkers.