We have successfully prepared a series of novel stable emulsions, of both simple and multiple types, containing ionic liquids and stabilised solely by silica nanoparticles.

We demonstrate that living cells can be encapsulated inside sporopollenin microcapsules derived from Lycopodium clavatum. To encapsulate large objects like cells, the sporopollenin particles are compressed into a pellet which forces their trilite scars to open up. Our method involves exposing a sporopollenin pellet to an aqueous suspension of cells in the presence of a surface active agent which facilitates the capillary suction of the cells suspension inside the compressed sporopollenin and its ''re-inflating'' and closure of trilite scars. We demonstrate that the viability of the cells is preserved after the encapsulation in the sporopollenin capsules which contain a significant amount of entrapped cells and show biological activity when placed into a culture medium. Since the sporopollenin nanopores allow nutrient transport across the capsule wall, it could be used for controlling the rate of in situ fermentation reactions or as bio-reactors. We also show that sporopollenin can be loaded with magnetic nanoparticles and live cultures simultaneously which would allow remote manipulation, fixation, removal or potentially targeted delivery of such bio-microreactors. The encapsulation of living cells inside sporopollenin can be used for many different purposes in the food and pharmaceutical industries, including protection of probiotics in foods and delivery of live vaccines for pharmaceutical applications.

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We report measured and calculated oil-ionic liquid, water-ionic liquid and oil-water contact angles on silica surfaces which have been hydrophobised to different extents by silanisation. Based on the idea that the contact angle formed by a liquid-liquid interface with a particle adsorbed at that interface is a key determinant of the strength of particle adsorption and the tendency of the adsorbed particle film to curve, we correlate the contact angle data with the phase inversion points and stabilities of the corresponding particle-stabilised emulsions.

Results are reported for ellipsometric measurements of hydrophobized monodisperse silica particles, with a diameter of about 25 nm, spread at the toluene-water interface. Theoretical values for the ellipsometric parameters are derived by treating the particles as a core-shell model and performing integrations of the refractive index profile through the interface using Drude's equations. With justifiable choices of the fixed parameters for the system, the agreement is good between measured and calculated values for the ellipsometric parameter Δ as a function of the amount of silica particles added to the interface. However, the results at high particle concentration at the interface are consistent either with coverage greater than a close-packed monolayer or with a monolayer with corrugations whose amplitude is less than the radius of the particles. The results show that this is not a suitable method for the determination of the contact angle of the particles at the oil-water interface.