Nanofibrillar cellulose hydrogels and reconstructed hydrogels as matrices for controlled drug release

Abstract

Concentrated 3% and 6.5% anionic nanofibrillar cellulose (ANFC) hydrogels were introduced as matrix reservoirs for controlled delivery applications of small molecules and proteins. A further aim was to study how the freeze-drying and subsequent rehydration of ANFC hydrogel affects the rheological properties and drug release of selected model compounds from the reconstructed hydrogels. It was demonstrated that the 3% and 6.5% ANFC hydrogels can be freeze-dried with suitable excipients into highly porous aerogel structures and redispersed back into the hydrogel form without significant change in the rheological properties. Freeze-drying did not affect the drug release properties from redispersed ANFC hydrogels, indicating that these systems could be stored in the dry form and only redispersed when needed. For large molecules, the diffusion coefficients were significantly smaller when higher ANFC fiber content was used, indicating that the amount of ANFC fibers in the hydrogel can be used to control the release rate. The release of small molecules was controlled with the ANFC fiber content only to a moderate extent. The results indicate that ANFC hydrogel can be used for controlled delivery of several types of molecules and that the hydrogel can be successfully freeze-dried and redispersed.

Fabrication of ultrathin nanocellulose shells on tough microparticlesviaan emulsion-templated colloidal assembly: towards versatile carrier materials

“…The release behaviours by the CNF shells were faster and more pH-selective than those of spray-dried CNF microparti- cles 33 or CNF-reinforced alginate microspheres, 34 likely because of the good dispersibility and well-defined structure of our microparticles. Generally, CNF gels show slow and sustained drug release properties over a period of several days 35,36 or months, 33,37 because the dense CNF network structure decreases the diffusivity of drug molecules. Although the CNFshells in this work did not show the slow and long-lasting release properties, this material showed unique pH-triggered release properties and good dispersibility with small sizes.…”

Opportunities of Bacterial Cellulose to Treat Epithelial Tissues

“…The three types of nanocellulose have been proposed for a diversity of medical and/or pharmaceutical applications. Regarding plant-derived nanocellulose hydrogels, recent encouraging applications include renewable and xeno-free wound dressings for skin graft donor sites [30] as well as controlled drug release platforms for both low and high molecular weight substances [31]. As an alternative to CNC and CNF, cellulose produced by microorganisms is emerging as a promising natural source of ready-to-use nanocellulose for medical and pharmaceutical applications.…”

Nanofibrillar cellulose wound dressing supports the growth and characteristics of human mesenchymal stem/stromal cells without cell adhesion coatings

“…NFC hydrogel has been shown to improve the formation of 3D tumor spheroids and to support the pluripotency of stem cells spheroids [23][24][25][26]. In addition to 3D cell culturing, NFC hydrogels can be utilized in the controlled release of drugs [27,28]. Furthermore, NFC hydrogel can be modified into different forms, such as films and dressings [29,30].…”