Loading and Protection of Hydrophilic Molecules into Liposome-Templated Polyelectrolyte Nanocapsules

Abstract

Compartmentalized systems produced via the layer-by-layer (LbL) self-assembly method have been produced by alternatively depositing alginate and chitosan layers onto cores of liposomes. The combination of dynamic light scattering (DLS), ζ potential, and transmission electron microscopy (TEM) techniques provides detailed information on the stability, dimensions, charge, and wall thickness of these polyelectrolyte globules. TEM microphotographs demonstrate the presence of nanocapsules with an average diameter of below 300 nm and with a polyelectrolyte wall thickness of about 20 nm. The possibility of encapsulating and releasing molecules from this type of nanocapsule was demonstrated by loading FITC-dextrans of different molecular weights in the liposome system. The release of the loaded molecules from the nanocapsule was demonstrated after liposome core dissolution. Even at low molecular weight (20 kDa), the nanocapsules appear to be appropriate for prolonged molecule compartmentalization and protection. By means of the Ritger-Peppas model, non-Fickian transport behavior was detected for the diffusion of dextran through the polyelectrolyte wall. Values of the diffusion coefficient were calculated and yield useful information regarding chitosan/alginate hollow nanocapsules as drug-delivery systems. The influence of the pH on the release properties was also considered. The results indicate that vesicle-templated hollow polyelectrolyte nanocapsules show great potential as novel controllable drug-delivery devices for biomedical and biotechnological applications.

Internal Structure of Matrix-Type Multilayer Capsules Templated on Porous Vaterite CaCO3 Crystals as Probed by Staining with a Fluorescence Dye

“…Matrix capsules are typically prone to a different release mechanism that is mostly determined by the composition and internal molecular structure of the matrix [ 22 ]. Some examples include poly( l -glutamic acid)/chitosan microcapsules templated on melamine formaldehyde [ 51 ], chitosan/alginate capsules built up on liposomes [ 52 ], or carrageenan/chitosan capsules deposited onto oil nanoemulsion droplets [ 53 ].…”

Rheological Properties of Alginate–Essential Oil Nanodispersions

“…Alginates are abundant in the environment since they are present both as a structural component in marine brown algae, and as capsular polysaccharides in soil bacteria. Alginate is recognized as a versatile biopolymer used in a broad range of applications [1][2][3][4][5]. Alginate is a linear binary copolymer made of blocks of mannuronic acid (M) and guluronic acid (G), covalently linked together in different sequences.…”

Polymer Capsules for Enzymatic Catalysis in Confined Environments

“…Cuomo and coworkers reported that low or high molecular weight molecules were released with a non-Fickian type of transport from polyelectrolyte capsules made of alginate and chitosan. The release rate decreased, while the molecular weight and the multishell thickness increased [42,43] (Figure 2).…”

“…Multilayer film PLL c /liposomes/PMAc/PVP/PMA SH [19,82] Alginate/Chitosan Multilayer film ALG/CHI [7,22,42,43] Poly(sodium-styrene sulfonate)/poly(allylamine) hydrochloride Multilayer film PSS/PAH [5] Glucose oxidase/Catalase Multilayer film GOX/CAT [79] Glucose oxidase/polyethylenimine/Catalase Multilayer film GOX/PEI/CAT [80]…”