Innovative Colorimetric NQO1 Detection Strategy via Substrate Competitive and Biomimetic Cascade Reactions with a...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• NAD(P)H: quinone oxidoreductase-1 (NQO1) is crucial for antioxidation and is often overexpressed in tumors.
• Accurate and rapid detection of NQO1 is vital for advancing cancer diagnosis.
• Current methods for NQO1 monitoring require improvement in speed and sensitivity.

Purpose of the Study:

• To develop a novel, sensitive colorimetric assay for NQO1 detection.
• To utilize a competitive substrate mechanism involving a nanozyme mimic.
• To enable differentiation of cancerous and noncancerous cells based on NQO1 activity.

Main Methods:

• A cobalt-nitrogen-doped carbon nanozyme (CoNC) was synthesized as an NADH oxidase (NOX) mimic.
• A dual-stage colorimetric assay was designed, leveraging differential NADH consumption and a secondary peroxidase-mimetic reaction.
• Prussian blue (PB) nanoparticles were used for signal amplification and quantification.

Main Results:

• The developed method achieved a low limit of detection (0.67 μg mL⁻¹) for NQO1.
• The assay successfully differentiated between cancerous and noncancerous cells based on NQO1 activity profiles.
• CoNC demonstrated high catalytic efficiency (5.2 U mg⁻¹), outperforming existing NOX mimics.

Conclusions:

• This study presents a transformative colorimetric strategy for sensitive NQO1 detection using nanozymes.
• The CoNC-based assay offers a promising tool for clinical diagnostics and cancer cell differentiation.
• CoNC's dual role as a mimic and in enzymatic regeneration broadens its potential in bioanalytical applications.