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Published on: October 17, 2016
Layer-by-layer polyelectrolyte coating of low molecular weight poly(lactic acid) nanoparticles
Samuli Hirsjärvi1, Leena Peltonen, Jouni Hirvonen
1Division of Pharmaceutical Technology, Faculty of Pharmacy, P.O. Box 56, FI-00014 University of Helsinki, Finland. samuli.hirsjarvi@helsinki.fi
Colloids and Surfaces. B, Biointerfaces
|April 18, 2006
Summary
This study demonstrates successful polyelectrolyte coating on low molecular weight poly(L-lactic acid) nanoparticles using a layer-by-layer technique. Chloroform solvent selection during nanoprecipitation is crucial for achieving effective coating due to enhanced nanoparticle surface charge.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Low molecular weight poly(L-lactic acid) (PLA) nanoparticles offer potential for controlled drug delivery.
- Challenges include aggregation and degradation, impacting coating processes.
- Polyelectrolyte (PE) coatings via layer-by-layer (LbL) assembly can enhance biocompatibility and drug release.
Purpose of the Study:
- To develop a robust LbL coating method for low M(w) PLA nanoparticles.
- To investigate the influence of solvent selection on PLA nanoparticle surface properties and subsequent LbL coating.
- To optimize PLA nanoparticles for advanced drug delivery systems.
Main Methods:
- Nanoprecipitation was used to prepare low M(w) PLA nanoparticles.
- Layer-by-layer (LbL) assembly with poly(allylamine hydrochloride) and poly(sodium 4-styrenesulfonate) was employed for nanoparticle coating.
- Solvent effects (chloroform vs. dichloromethane) on nanoparticle surface properties and coating success were evaluated.
Main Results:
- Successful LbL coating was achieved exclusively when chloroform was used as the solvent during PLA nanoparticle preparation.
- Nanoparticles prepared with chloroform exhibited a more charged surface compared to those prepared with dichloromethane.
- This increased surface charge facilitated effective polyelectrolyte multilayer formation.
Conclusions:
- Solvent selection during nanoprecipitation critically influences the surface charge of low M(w) PLA nanoparticles.
- A more charged nanoparticle surface, achieved with chloroform, is essential for successful LbL polyelectrolyte coating.
- This finding provides a pathway for developing improved PLA-based nanoparticle drug delivery systems.
