Formulation, characterisation and application of microencapsulated systems for pharmaceutical and food purposes

This thesis describes the formulation, production and characterisation of different microencapsulated systems for pharmaceutical and food purposes. Several microencapsulation techniques (ionotropic gelation, spray drying, spray congealing, microfluidics, and solvent evaporation) were investigated. Ionotropic gelation was selected for the microencapsulation of Artemisia absinthium L. ethanolic extract and vitamin D oily solution into alginate-based microspheres destined to be an innovative ingredient for the dough of baked products, to verify the impact of phytocomplex bitter compounds on appetite and to increase the uptake of Vit D, respectively. Microparticles were successfully prepared, characterised and inserted into biscuit dough in both cases. Spray drying was used to microencapsulate a Thymus vulgaris L. hydroalcoholic extract with the final goal of applying the obtained system as an innovative ingredient with preserving activity for meat-based products to partially or totally substitute nitrite salts actually used. Spray congealing was used to microencapsulate a soluble model drug (metoclopramide hydrochloride) into different lipid excipients for a long-lasting release. Microparticles were produced starting from water-in-oil (W/0) emulsions, characterised for dimensions, morphology, and residual moisture and in vitro drug release was performed. Droplet microfluidics and solvent evaporation were used to produce PLGA-based microparticles containing different loadings of lidocaine to guarantee a modified/prolonged drug release. Microparticles were then characterised for morphology, dimensions, swelling behaviour and drug release.