Molecular Design of Microcapsule Shells for Visible Light-Triggered Release.

The development of photo-responsive capsules to tune and control the sustained-release of encapsulated actives is a fascinating and challenging route to improve the performances and effectiveness of a wide range of delivery applications. In this work, we report the preparation of visible light-responsive capsules obtained via oil-in-water interfacial polycondensation between modified diacyl-chloride azobenzene moiety and diamine flexible spacer in the presence of cross-linkers with different structures and functionalities. The effect on the release profile of the encapsulated perfume oil was investigated using three flexible spacers with different lengths (1,8-diaminooctane; 1,6-diaminohexane and 1,4-diaminobutane) and two types of cross-linkers (1,3,5-benzenetricarbonyl trichloride and melamine).

Ball milling: a green technology for the preparation and functionalisation of nanocellulose derivatives.

Ball milling is a simple, fast, cost-effective green technology with enormous potential. One of the most interesting applications of this technology in the field of cellulose is the preparation and the chemical modification of cellulose nanocrystals and nanofibers. Although a number of studies have been reported in the literature, the potential of this technique in the field of cellulose nanoparticles has not been fully exploited.

Nanocellulosic materials as bioinks for 3D bioprinting.

3D bioprinting is a new developing technology with lots of promise in tissue engineering and regenerative medicine. Being biocompatible, biodegradable, renewable and cost-effective, cellulosic nanomaterials have recently captured the attention of researchers due to their applicability as inks for 3D bioprinting. Although a number of cellulose-based bioinks have been reported, the potential of cellulose nanofibrils and nanocrystals has not been fully explored yet.

Rational design of heat-set and specific-ion-responsive supramolecular hydrogels based on the Hofmeister effect.

Smart supramolecular hydrogels have been prepared from a bolaamphiphilic L-valine derivative in aqueous solutions of different salts. The hydrogels respond selectively to different ions and are either reinforced or weakened. In one case, in contrast to conventional systems, the hydrogels are formed upon heating of the system.

Freezing capture of polymorphic aggregates of bolaamphiphilic (L)-valine-based molecular hydrogelators.

Nanostructured xerogels have been prepared by the freeze-drying of hydrogels and aggregates formed by bolaamphiphilic L-valine derivatives after aging under different environmental conditions. A wide variety of shapes and sizes has been achieved by a simple methodology. These nanostructures have been studied by SEM and WAXD and a dramatic influence of structural flexibility on the kinetics of aggregation has been observed.

Interplay of molecular hydrogelators and SDS affords responsive soft matter systems with tunable properties.

The gelation efficiency of low molecular weight bolaamphiphilic hydrogelators 1 and 2 is influenced by the presence of SDS micelles. Similarly, the critical micellar concentration value of SDS is reduced in the presence of the studied molecular hydrogelators. Rheological measurements indicate that the strength of the hydrogels can be modulated with SDS, the gels becoming weaker in the presence of micelles.

Molecular hydrogels from bolaform amino acid derivatives: a structure-properties study based on the thermodynamics of gel solubilization.

Insight is provided into the aggregation thermodynamics associated to hydrogel formation by molecular gelators derived from L-valine and L-isoleucine. Solubility data from NMR measurements are used to extract thermodynamic parameters for the aggregation in water. It is concluded that at room temperature and up to 55 °C, these systems form self-assembled fibrillar networks in water with quite low or zero enthalpic component, whereas the entropy of the aggregation is favorable.