ABSTRACT
Water-in-oil (W/O) emulsions have high potential for several industrial areas as delivery systems of hydrophilic compounds. In general, they are less studied than oil-in-water (O/W) systems, namely in what concerns the so-called fluid systems, partly due to problems of instability. In this context, this work aimed to produce stable W/O emulsions from a natural oil, sweet almond oil, to be further tested as vehicles of natural hydrophilic extracts, here exemplified with an aqueous cinnamon extract. Firstly, a base W/O emulsion using a high-water content (40/60, v/v) was developed by testing different mixtures of emulsifiers, namely Tween 80 combined with Span 80 or Span 85 at different contents. Among the tested systems, the one using a 54/46 (v/v) Span 80/Tween 80 mixture, and subjected to 12 high-pressure homogenizer (HPH) cycles, revealed to be stable up to 6 months, being chosen for the subsequent functionalization tests with cinnamon extract (1.25-5%; w/v; water-basis). The presence of cinnamon extract leaded to changes in the microstructure as well as in the stability. The antimicrobial and antioxidant analysis were evidenced, and a sustained behavior compatible with an extract distribution within the two phases, oil and water, in particular for the higher extract concentration, was observed.
Subject(s)
Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Drug Carriers/chemistry , Emulsions/chemistry , Oils/chemistry , Water/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Cinnamomum zeylanicum/chemistry , Hydrophobic and Hydrophilic Interactions , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Extracts/pharmacologyABSTRACT
Chitosan (CHI) nanoparticles present promising applications in pharmaceutical and biomedical fields, including drug and gene delivery. Among different approaches, microfluidics emerges as a resourceful tool for nanoparticle production in low-cost, reproducible processes with predictable fluid dynamics. However, microfluidic-assisted synthesis of CHI nanoparticles has not been widely explored in the literature. In this context, we systematically investigated different process parameters that influence the synthesis of CHI/ATP nanoparticles. We highlight the effects and limitations of diffusion and distinct mixing patterns developed through the microchannels on the final physicochemical characteristics of CHI/ATP nanoparticles produced. To address these hurdles, here we describe a simple, feasible, and reproducible method for the production of CHI/ATP nanoparticles. This strategy enables the development of a continuous and homogeneous production process for CHI nanoparticles to be applied in the most varied fields of research.
