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Particles without a Box: Brush-first Synthesis of Photodegradable PEG Star Polymers under Ambient Conditions
Published on: October 10, 2013
Rapid cellular internalization of multifunctional star polymers prepared by atom transfer radical polymerization
Hong Y Cho1, Haifeng Gao, Abiraman Srinivasan
1Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Biomacromolecules
|September 14, 2010
Summary
Synthesized poly(ethylene glycol) star polymers with GRGDS peptides demonstrate biocompatibility and rapid cellular uptake in bone cells. These functional star polymers show enhanced delivery potential for biomedical applications.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Cell Biology
Background:
- Poly(ethylene glycol) (PEG) star polymers are investigated for drug delivery and tissue engineering.
- Incorporating peptide sequences like GRGDS can enhance cellular interactions and targeting.
Purpose of the Study:
- To synthesize and characterize PEG star polymers functionalized with GRGDS peptides.
- To evaluate the biocompatibility and cellular uptake of these functionalized star polymers.
Main Methods:
- Synthesis via atom transfer radical polymerization (ATRP) using PEGMA, GRGDS-PEG-Acryl, FMA, and EGDMA.
- Characterization using dynamic light scattering, atomic force microscopy, fluorescence microscopy, and 1H NMR spectroscopy.
- In vitro studies with MC3T3-E1.4 cells to assess biocompatibility and cellular uptake via confocal microscopy and flow cytometry.
Main Results:
- PEG star polymers with an approximate diameter of 20 nm were successfully synthesized.
- Successful conjugation of fluorescein and GRGDS peptides to the star polymer periphery was confirmed.
- Star polymers exhibited high biocompatibility (≥ 90% cell viability) and rapid cellular uptake, especially those with GRGDS peptides.
Conclusions:
- Synthesized PEG star polymers are biocompatible and can be efficiently internalized by cells.
- The presence of GRGDS peptides significantly enhances cellular uptake, indicating potential for targeted delivery applications.
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