Fluorescent Poly(ε-Caprolactone)s Micelles for Anticancer Drug Delivery and Bioimaging.

Area of Science:

• Polymer Chemistry
• Nanomedicine
• Biomaterials

Background:

• Clinical translation of polymer-based nanomedicines is hindered by premature drug release and low drug-loading capacity (DLC).
• Existing systems often lack inherent therapeutic and bioimaging functionalities, limiting their clinical applicability.
• Biodegradable micellar drug delivery systems require enhanced stability and controlled release mechanisms.

Purpose of the Study:

• To design a novel poly(ε-caprolactone) (PCL)-based amphiphilic diblock copolymer for advanced nanomedicine applications.
• To create a multifunctional micellar system with inherent anticancer activity, fluorescence imaging, and multistimuli-responsive drug release.
• To overcome limitations of current nanomedicines, including premature drug release and low DLC.

Main Methods:

• Synthesis of a PCL-based amphiphilic diblock copolymer with a fluorescent hydrophilic shell and a hydrophobic core.
• Incorporation of anticancer naphthalene moieties into the hydrophobic core to enhance drug loading via π-π interactions with doxorubicin (DOX).
• Characterization of micelle properties, including critical micelle concentration (CMC), stability, drug loading capacity (DLC), and in vitro cytotoxicity.

Main Results:

• The novel PCL micelles exhibited a low CMC (7.8 × 10⁻³ g/L) and excellent stability for long-term storage.
• Enhanced DLC of 3.7% was achieved through π-π interactions between naphthalene moieties and DOX.
• The micelles demonstrated significant cytotoxicity against the MDA-MB-231 cell line, indicating combined therapeutic efficacy.
• The triethylene glycol units in the shell provided thermoresponsive behavior for precise drug release and enabled intracellular tracking.

Conclusions:

• The developed PCL-based micellar system offers a promising platform for advanced nanomedicine, addressing key limitations in drug delivery.
• The inherent therapeutic and bioimaging functionalities, coupled with enhanced DLC and controlled release, highlight the potential for improved cancer treatment.
• This multifunctional nanomedicine demonstrates significant potential for clinical translation due to its stability, efficacy, and advanced features.