Moderately stable emulsions produced by a double syringe method

Different emulsification techniques lead to emulsions with different targeted properties specific to their intended use. In this study, emulsions are generated using several emulsification techniques. They are compared as regards the component droplet size distribution and their stability in time. A particular technique based on the Tessari (known as double syringe system - DSS, as well) method - used originally for foam generation - is evaluated for emulsion production. Results show that DSS method leads to emulsions with mean droplet size about two orders of magnitude larger than in the case of emulsions obtained by conventional high speed and high pressure homogenizers (HPH). However, DSS emulsions have comparable viscosity behavior with the emulsions obtained by conventional methods and are stable for time intervals of a couple of hours which is convenient for specific medical applications. Furthermore, this study evaluates the effect of small quantities of some emulsion stabilizers on the mean droplet size distribution of emulsions. In the examined narrow range of values no significant modifications of the mean droplet size distribution was observed. (C) 2014 Elsevier B.V. All rights reserved.