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Updated: Jan 31, 2026
07:14
In situ Photo-rheology Monitors Viscoelastic Changes in Photo-responsive Polymer Networks
Published on: June 20, 2025
905
Naphthalene-Derived Photo-Switchable Hyperbranched Polymer by Anionic Polymerization for the Early Stage Detection
Narayan Das1, Tapendu Samanta1, Srishti Gautam1
1Polymer Research Centre, Department of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata, India, West Bengal, PIN-741246, India.
Bioconjugate Chemistry
|January 29, 2026
Summary
Researchers developed a novel polymer, PNap-Azo, that changes shape in hypoxic environments. This photoswitchable polymer detects azoreductase activity, offering potential for real-time monitoring in conditions like tumors.
Area of Science:
- Polymer Chemistry
- Biomedical Engineering
- Materials Science
Background:
- Hyperbranched polymers offer unique properties for biomedical applications.
- Controlled branching via hyperbranched polymerization is gaining attention.
- Stimulus-responsive polymers are crucial for targeted therapies and diagnostics.
Purpose of the Study:
- To develop a naphthalene-derived, photoswitchable, self-assembling hyperbranched polymer (PNap-Azo).
- To investigate PNap-Azo's potential in hypoxic microenvironments for diagnosis and drug delivery.
- To utilize the azo bond's responsiveness to an overexpressed enzyme in hypoxic conditions.
Main Methods:
- Synthesis of PNap-Azo via hyperbranched polymerization in an aqueous medium.
- Investigating the cis-trans isomerization of the azo bond upon enzymatic stimulus.
- Characterizing the polymer's morphology, amphiphilicity, and hydrogen bonding.
- Verifying azoreductase activity detection through turn-on fluorescence responses spectroscopically and in live cell lines.
Main Results:
- PNap-Azo exhibits a shape transformation from spherical to twisted-rod upon cis-trans isomerization.
- The polymer demonstrates excellent twisted-rod morphology due to amphiphilicity and hydrogen bonding.
- PNap-Azo successfully detects and monitors azoreductase activity in hypoxic environments via turn-on fluorescence.
- Real-time monitoring of azoreductase activity was validated in live cell lines.
Conclusions:
- PNap-Azo is a novel photoswitchable hyperbranched polymer with significant biological impact in hypoxic environments.
- The polymer's stimulus-responsive nature enhances therapeutic efficacy in hypoxic tumor environments.
- PNap-Azo provides a platform for real-time monitoring of azoreductase activity, potentially aiding in early complication prevention.
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