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Injectable Supramolecular Polymer-Nanoparticle Hydrogels for Cell and Drug Delivery Applications
Published on: February 7, 2021
Hydrogels as intracellular depots for drug delivery
Kimberly Ann V Zubris1, Yolonda L Colson, Mark W Grinstaff
1Departments of Biomedical Engineering and Chemistry, Boston University, Boston, Massachusetts 02215, United States.
Molecular Pharmaceutics
|November 8, 2011
Summary
Micrometer-sized hydrogels are taken up by lung cancer cells and swell in acidic conditions to release drugs. These nanoparticles act as intracellular drug depots, concentrating chemotherapy locally for enhanced treatment.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Cancer Therapeutics
Background:
- Developing effective drug delivery systems for cancer treatment is crucial.
- Intracellular drug delivery requires nanoparticles that can navigate cellular environments and release therapeutic payloads.
- Controlling nanoparticle structure and drug release within cancer cells remains a challenge.
Purpose of the Study:
- To describe the intracellular activity and drug depot characteristics of micrometer-sized hydrogels.
- To evaluate the potential of these hydrogels as intracellular drug depots for cancer chemotherapy.
- To investigate the drug release mechanism and drug-nanoparticle interactions.
Main Methods:
- Synthesis of micrometer-sized polymeric nanoparticles.
- Assessment of cellular uptake in A549 human non-small cell lung cancer cells.
- Evaluation of nanoparticle swelling and transformation in response to acidic conditions.
- In vitro drug delivery studies using paclitaxel.
Main Results:
- Nanoparticles demonstrated rapid uptake into A549 cells (88.3% in 24 h).
- Hydrogel structure transformed from hydrophobic to hydrophilic in mildly acidic conditions, releasing encapsulated drug.
- Paclitaxel showed a 3- to 4-fold increased affinity for the expanded nanoparticle state.
- Effective in vitro delivery of chemotherapeutics was achieved.
Conclusions:
- Micrometer-sized hydrogels are efficiently internalized by lung cancer cells.
- The pH-responsive swelling behavior enables controlled intracellular drug release.
- These nanoparticles function as effective intracellular drug depots, concentrating chemotherapy locally.
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