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Updated: Jul 14, 2026
07:32
Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
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Functional Biodegradable Nitric Oxide Donor-Containing Polycarbonate-Based Micelles for Reduction-Triggered Drug
ACS Macro Letters
|May 27, 2022
Summary
This study developed novel polymeric nitric oxide (NO) donors in micelles to combat multidrug resistance (MDR) in cancer. The system enhanced chemotherapy efficacy and reduced side effects in vivo.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Cancer Therapy
Background:
- Nitric oxide (NO) can reverse multidrug resistance (MDR) in tumors, but its delivery is challenging.
- Developing stable, controlled NO release systems is crucial for MDR cancer treatment.
Purpose of the Study:
- To design and synthesize polymeric nitric oxide (NO) donors for enhanced cancer chemotherapy.
- To create biodegradable micelles for stabilizing NO and enabling triggered release.
- To evaluate the efficacy of NO-releasing micelles in overcoming drug resistance in breast cancer cells.
Main Methods:
- Synthesized cyclic nitrate trimethylene carbonate (NTC) monomer and polymerized it into amphiphilic copolymers.
- Self-assembled copolymers into biodegradable micelles (NO-M) for NO stabilization.
- Investigated NO release triggered by intracellular reduction conditions.
- Assessed NO-M's effect on P-glycoprotein (P-gp) expression and chemosensitivity in MCF7/DOX^R cells.
- Evaluated DOX-loaded NO-M (NO-M@DOX) for drug release, cellular accumulation, and in vivo antitumor activity.
Main Results:
- Developed biodegradable NO-M micelles (130 nm) that stabilize NO donors.
- Achieved triggered NO release under intracellular reduction conditions.
- Demonstrated NO-M's ability to inhibit P-gp expression and enhance chemosensitivity in drug-resistant MCF7 cells.
- NO-M@DOX showed enhanced intracellular DOX accumulation and superior antitumor activity via combined NO/DOX release.
- In vivo studies confirmed effective tumor suppression with reduced side effects.
Conclusions:
- Polymeric NO donors encapsulated in biodegradable micelles offer a promising strategy for MDR cancer therapy.
- The developed NO-M@DOX system effectively reverses MDR and enhances chemotherapy through controlled NO and drug release.
- This approach demonstrates significant potential for improving cancer treatment outcomes with fewer adverse effects.
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