Responsive layer-by-layer materials for drug delivery

Wohl, Benjamin M.; Engbersen, Johan F.J.

doi:10.1016/j.jconrel.2011.08.035

Cited by 193 publications

(139 citation statements)

References 177 publications

Supporting

Mentioning

138

Contrasting

Unclassified

Order By: Relevance

“…Most of the earlier studies on polyelectrolyte complexation focused on coacervation of natural polymers such as albumin and gelatin, but recent studies [2,3,[8][9][10][11][12] have extended this to the complexation of synthetic polyelectrolytes. Renewed scientific interest in polyelectrolyte complexation is due, in part, to its use in polyelectrolyte assemblies and multilayer films [13,14], which have many technological applications [15,16].…”

Section: Introductionmentioning

confidence: 99%

pH and Salt Effects on the Associative Phase Separation of Oppositely Charged Polyelectrolytes

et al. 2014

View full text Add to dashboard Cite

Abstract:The classical Voorn-Overbeek thermodynamic theory of complexation and phase separation of oppositely charged polyelectrolytes is generalized to account for the charge accessibility and hydrophobicity of polyions, size of salt ions, and pH variations. Theoretical predictions of the effects of pH and salt concentration are compared with published experimental data and experiments we performed, on systems containing poly(acrylic acid) (PAA) as the polyacid and poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) or poly(diallyldimethyl ammonium chloride) (PDADMAC) as the polybase. In general, the critical salt concentration below which the mixture phase separates, increases with degree of ionization and with the hydrophobicity of polyelectrolytes. We find experimentally that as the pH is decreased below 7, and PAA monomers are neutralized, the critical salt concentration increases, while the reverse occurs when pH is raised above 7. We predict this asymmetry theoretically by introducing a large positive Flory parameter (= 0.75) for the interaction of neutral PAA monomers with water. This large positive Flory parameter is supported by molecular dynamics simulations, which show much weaker hydrogen bonding between neutral PAA and water than between charged PAA and water, while neutral and charged PDMAEMA show similar numbers of hydrogen bonds. This increased hydrophobicity of neutral PAA at reduced pH increases the tendency towards phase separation despite the reduction in charge interactions between the polyelectrolytes. Water content and volume of coacervate are found to be a strong function of the pH and salt concentration.

show abstract

Section: Introductionmentioning

confidence: 99%

pH and Salt Effects on the Associative Phase Separation of Oppositely Charged Polyelectrolytes

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Layer-by-layer assembly of polysaccharide-based multilayer films on colloidal particles offer numerous possibilities in the design of nanocontainers for the controlled release of drug molecules. In particular, polyelectrolyte multilayer coatings on non-spherical particles have recently attracted attention, as it has been shown that not only size but also shape influences the pharmacokinetics of the drug carriers [13][14][15]. weeks at room temperature [16].…”

Section: Introductionmentioning

confidence: 99%

Influence of charge density and calcium salt on stiffness of polysaccharides multilayer film

Milkova

Radeva

2015

Colloids and Surfaces A: Physicochemical and Engineering Aspect

View full text Add to dashboard Cite

“…31 The electrostatically anchored multilayer structure provided a controlled release of the loading cargo, which is pivotal for local drug delivery in order to obtain a sustained effect. [32][33][34] H1299 originates from epithelial lung cancer and has a prominent ability of endocytosis. Therefore, it is an ideal cell line for validating CS parameters for siRNA delivery.…”

Section: Discussionmentioning

confidence: 99%

Chitosan/siRNA functionalized titanium surface via a layer-by-layer approach for in vitro sustained gene silencing and osteogenic promotion

Song¹,

Song²,

Yang³

et al. 2015

IJN

View full text Add to dashboard Cite

Titanium surface modification is crucial to improving its bioactivity, mainly its bone binding ability in bone implant materials. In order to functionalize titanium with small interfering RNA (siRNA) for sustained gene silencing in nearby cells, the layer-by-layer (LbL) approach was applied using sodium hyaluronate and chitosan/siRNA (CS/siRNA) nanoparticles as polyanion and polycation, respectively, to build up the multilayered film on smooth titanium surfaces. The CS/siRNA nanoparticle characterization was analyzed first. Dynamic contact angle, atomic force microscopy, and scanning electron microscopy were used to monitor the layer accumulation. siRNA loaded in the film was quantitated and the release profile of film in phosphate-buffered saline was studied. In vitro knockdown effect and cytotoxicity evaluation of the film were investigated using H1299 human lung carcinoma cells expressing green fluorescent protein (GFP). The transfection of human osteoblast-like cell MG63 and H1299 were performed and the osteogenic differentiation of MG63 on LbL film was analyzed. The CS/siRNA nanoparticles exhibited nice size distribution. During formation of the film, the surface wettability, topography, and roughness were alternately changed, indicating successful adsorption of the individual layers. The scanning electron microscope images clearly demonstrated the hybrid structure between CS/siRNA nanoparticles and sodium hyaluronate polymer. The cumulated load of siRNA increased linearly with the bilayer number and, more importantly, a gradual release of the film allowed the siRNA to be maintained on the titanium surface over approximately 1 week. In vitro transfection revealed that the LbL film-associated siRNA could consistently suppress GFP expression in H1299 without showing significant cytotoxicity. The LbL film loading with osteogenic siRNA could dramatically increase the osteogenic differentiation in MG63. In conclusion, LbL technology can potentially modify titanium surfaces with specific gene-regulatory siRNAs to enhance biofunction.

show abstract

Responsive layer-by-layer materials for drug delivery

Cited by 193 publications

References 177 publications

pH and Salt Effects on the Associative Phase Separation of Oppositely Charged Polyelectrolytes

pH and Salt Effects on the Associative Phase Separation of Oppositely Charged Polyelectrolytes

Influence of charge density and calcium salt on stiffness of polysaccharides multilayer film

Chitosan/siRNA functionalized titanium surface via a layer-by-layer approach for in vitro sustained gene silencing and osteogenic promotion

Contact Info

Product

Resources

About