LAUSR

Cellulose nanocrystals (CNC)-based foams are promising tissue engineering materials that may facilitate implant-tissue integration and allow localized and controlled drug delivery. Herein, hybrid CNC-based foams, which are ultralightweight (30 to 100 mg cm-3 ), highly porous (> 95%), ominiphilic and superabsorbent (1500 to 3000 wt% of water and/or toluene uptake) are obtained by the in-situ condensation of poly(ethylene glycol) ditriethoxysilyl (TES-PEG-TES) into a three-dimensional network, where silsesquioxane nanoparticles (SS-NP) are the cross-linking nodes, and CNC are entangled and forming ionic interactions, resulting in a supramolecular structure. In a new approach, using 3-mercaptopropyltrimethoxysilane, sulfhydryl groups are inserted on the SS-NP periphery and S-nitrosated to enable the functionalization of SS-NP with S-nitrosothiol groups, which are capable of releasing nitric oxide (NO), in a process triggered by the hydration of the foams and modulated by the supramolecular structure of the foams. CNC-SS-PEG foams exhibit elevated thermal and structural stability, compressive strength compatible with various soft human tissues, and NO release rates (1 - 18 pmol mg-1 min-1 ) within the range of the beneficial NO actions. Thus, the CNC-SS-PEG foams herein described represent a new platform of supramolecular hybrid materials for localized delivery of NO, with potential uses in tissue engineering and other biomedical applications. This article is protected by copyright. All rights reserved.