Quercetin Nanoparticle-Based Hypoxia-Responsive Probe for Cancer Detection.

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Materials Science

Background:

• Hypoxic tumors are a hallmark of many cancers, posing challenges for diagnosis and treatment.
• Developing sensitive and specific detection methods for tumor hypoxia is crucial for effective cancer therapy.
• Flavonoids, like quercetin (QCT), offer potential as biocompatible materials for nanomedicine.

Purpose of the Study:

• To develop a functional nanosystem for detecting tumor hypoxia.
• To utilize quercetin (QCT) as a polyphenolic core for nanomaterial fabrication.
• To create a pH-responsive system for fluorescent signal activation in acidic tumor microenvironments.

Main Methods:

• A phenolic-enabled nanotechnology strategy was employed to create quercetin (QCT) nanoparticles.
• Quercetin nanoparticles were coated with polyethylene glycol (PEG) for stability.
• A flavylium dye (Flav) was loaded as a pH indicator, forming the Flav@QCT-PEG nanosystem.
• The pH-responsive behavior of Flav@QCT-PEG in acidic conditions (pH 5) was investigated.

Main Results:

• The Flav@QCT-PEG nanosystem demonstrated pH-dependent collapse in acidic environments.
• Acidic conditions triggered the release of the flavylium dye (Flav), activating a fluorescent signal.
• The nanosystem effectively detected hypoxic tumors, which are characterized by acidity.
• The response of Flav@QCT-PEG to hypoxic environments was dose- and time-dependent.

Conclusions:

• The developed Flav@QCT-PEG nanosystem is a promising tool for detecting tumor hypoxia.
• This phenolic-enabled nanotechnology strategy offers a novel approach for creating responsive nanomaterials.
• The pH-sensitive fluorescent activation provides a mechanism for visualizing and quantifying hypoxic regions in tumors.