Hydrogen-bonded layer-by-layer films of poly(d,l-lactic-co-glycolic acid)-b-poly(ethylene glycol) polymersomes and tannic acid

Çalış, Gökçe
Poly(lactic-co-glycolic acid)-b-poly(ethylene glycol) (PLGA-b-PEG) can self-assemble into core/shell nanostructures in aqueous environment due to its amphiphilic nature. These nanostructures have been widely used as drug carriers in the biomedical applications due to biocompatibility and biodegradability of PLGA-b-PEG. Biodegradable character of the nanostructures provides an advantage for controlled drug delivery systems. The drug release occurs through hydrolytic degradation of PLGA core. There are studies reporting on the aqueous solution behavior of PLGA-b-PEG nanocarriers. However, there are limited numbers of studies concerning use of PLGA-b-PEG polymersomes as building blocks in preparation of layer-by-layer (LbL) self-assembled films. In this study, Doxorubicin and Paclitaxel loaded PLGA-b-PEG polymersomes were prepared and used as building blocks together with Tannic Acid (TA) in the preparation of LbL films. It was shown that multilayer deposition conditions affected the kinetics of drug release from the surface at acidic conditions. Moreover, it was demonstrated that release kinetics could also be controlled by constructing barrier layers within the LbL films. Incorporation of PLGA-b-PEG polymersomes into multilayers is important to increase the loading capacity of the films and to enhance the stability of polymersomes in the bloodstream. Considering the biodegradability of PLGA-b-PEG, important biological properties of TA and controllable release kinetics via LbLfilm architecture, such multilayers may be promising for controlled delivery applications from surfaces.


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Citation Formats
G. Çalış, “Hydrogen-bonded layer-by-layer films of poly(d,l-lactic-co-glycolic acid)-b-poly(ethylene glycol) polymersomes and tannic acid,” M.S. - Master of Science, Middle East Technical University, 2017.