Formation of Biocompatible Nanocapsules with Emulsion Core and Pegylated Shell by Polyelectrolyte Multilayer Adsorption

Abstract

The aim of this work was to develop a novel method of preparation of loaded nanosize capsules based on liquid core encapsulation by biocompatible polyelectrolyte (PE) multilayer adsorption, with or without pegylated outermost layer. Using AOT (docusate sodium salt) as emulsifier, we obtained cores, stabilized by an AOT/PLL (poly-L-lysine hydrobromide) surface complex. These positively charged cores were encapsulated by layer-by-layer adsorption of polyelectrolytes, biocompatible polyanion PGA (poly-L-glutamic acid sodium salt), and biocompatible polycation PLL. We used the saturation method for formation of consecutive layers, and we determined the optimal conditions concerning concentration of surfactant and polyelectrolytes to form stable shells. The average size of the obtained capsules was 60 nm. Pegylated external layer were prepared using PGA-g-PEG (PGA grafted by PEG poly(ethylene glycol)). The capsules were stable for at least a period of 3 months. These nanocapsules were biocompatible when tested for cytotoxicity in a cellular coculture assay and demonstrated no or very low nonspecific binding to peripheral blood mononuclear cells when tested by flow cytometry. In order to study drug effects on leukemia cells, beta-carotene and vitamin A have been encapsulated as model drugs.

Polyelectrolyte-coated nanocapsules containing undecylenic acid: Synthesis, biocompatibility and neuroprotective properties

“…Nanocapsules were synthesized using the method described by Szczepanowicz et al [31] and repeatedly cited in further papers [11,16,[32][33][34][35][36]. Briefly, nanocapsules' synthesis was based on direct encapsulation of emulsion cores in (bio)polyelectrolyte multilayer shells.…”

“…1a). PEG-ylated polyelectrolyte (PGA-gPEG) was synthesized using Me-PEG-NH 2 -methoxypolyethylene glycol amine according to Szczepanowicz et al [16]. Drug-loaded nanocapsules were synthesized as described above except that prior to the emulsification process, model drug (UDA) was dissolved in AOT/HCCl 3 mixture.…”

“…In the present work nanocapsules with the core-shell structure were synthesized using nanoemulsification and the layer-by-layer (LbL) saturation method analogous to the method described previously [11,16,[32][33][34][35][36][44][45][46]. Emulsion cores were formed by addition of oil phase to polycation solution during mixing with the magnetic stirrer at 300 rpm.…”

“…emulsion) core surrounded by a polymeric functionalized shell [9]. There is a number of research on encapsulation of nano-or microemulsion droplets by the sequential adsorption of (bio)polyelectrolytes to form nanocarierrs as drug delivery vehicles for hydrophobic drugs [10][11][12][13][14][15][16]. Nanocapsules exhibit similarity in their size and morphology to the natural occurring carriers such as serum lipoproteins [17].…”

Theoretical and experimental studies of drop size in membrane emulsification – Single pore studies of hydrodynamic detachment of droplets

“…The cyclohexane was chosen as the oil phase in which oil soluble ionic surfactant, docusate sodium (AOT), was dissolved to obtain concentration 5 × 10 −6 M or 1 × 10 −4 M. This two-component system is important from the practical point of view, since it can be used for the formation of microcapsules [32]. Shell of these microcapsules can be then formed by the sequential adsorption of polyelectrolytes [36,37], with PDADMAC as the first polycation layer. Steel needle was used for droplet formation to avoid problems with hydrophobization of capillary.…”