Physico-chemical characterization of self-emulsifying drug delivery systems.

Self-emulsifying drug delivery systems (SEDDS) are regarded as a potential implement for oral delivery of water insoluble APIs to overcome their poor and irregular bioavailability. The correlation between the physicochemical parameters and the behavior of self-emulsifying drug delivery systems was established. The objective of this study was to summarize these physicochemical factors characterized SEDDS. Determination of self-emulsification process and ternary phase diagram are the basis of preparations. The position of APIs in SEDDS inclusion can be determined by dye solubilisation test. The end point of self-emulsification was controlled by turbimetric evaluation. Optimisation of droplet size and zeta potential are crucial parameters because they can influence i.e. the dissolution rate of APIs and the stability of SEDDS. Besides the basic methods in the characterization of SEDDS such as dispersibility tests, turbidimetric evaluation, viscosity tests, determinations with complex instruments such as photon correlation spectroscopy or dynamic light-scattering, electro kinetic potential measurement, non-destructive spectroscopic techniques (LFDS, FTIR, RS) and various microscopic techniques (SEM, PLM, EDS) has also been described.