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Oligo(ethylene glycol) Methacrylate Copolymer-Modified Liposomes for Temperature-Responsive Drug Delivery System
Maria Isabel Martinez Espinoza1, Sezen Gül1, Luisa Mugnaini1
1Department of Chemistry, Materials and Chemical Engineering "G. Natta", Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy.
Molecules (Basel, Switzerland)
|December 17, 2024
Summary
Thermoresponsive polymers were integrated into thermosensitive liposomes (TSLs) to enhance controlled drug release. While copolymer incorporation slightly reduced drug loading, it improved TSL thermoresponsiveness, optimizing thermally triggered delivery.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Thermosensitive liposomes (TSLs) are promising for controlled drug release, but require precise thermal triggers.
- Thermoresponsive polymers offer tunable thermal behavior for advanced biomedical applications.
- Integrating polymers into TSLs can modify their physicochemical properties and release kinetics.
Purpose of the Study:
- To synthesize a thermoresponsive copolymer, Chol-P(MEO2MA-co-OEGMA), for TSL applications.
- To incorporate the synthesized copolymer into various TSL formulations.
- To evaluate the impact of copolymer incorporation on TSL characteristics and thermoresponsive drug release.
Main Methods:
- Synthesis of a thermoresponsive copolymer using Atom Transfer Radical Polymerization (ATRP).
- Incorporation of the copolymer into liposomes composed of various phospholipids (DPPC, Lyso-PC, HSPC, DSPC).
- Characterization of liposome physicochemical properties (size, PDI, LE, EE) using dynamic light scattering and fluorescence spectroscopy.
- Evaluation of drug release profiles, including the effect of molecular weight on loading efficiency.
Main Results:
- The copolymer exhibited a lower critical solution temperature (LCST) of 37 °C, suitable for thermal triggering.
- Copolymer incorporation slightly altered liposome size and generally decreased loading efficiency (LE) and encapsulation efficiency (EE).
- HSPC-based TSLs demonstrated enhanced thermoresponsiveness upon copolymer modification, despite reduced loading capacity.
- Lyso-PC formulations showed lower LE and EE, potentially due to instability during purification.
Conclusions:
- Thermoresponsive copolymers can be successfully incorporated into TSLs.
- Copolymer modification can enhance the thermal responsiveness of TSLs, particularly in HSPC formulations.
- This strategy holds potential for optimizing targeted, thermally triggered drug delivery systems.
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