Microemulsion preservation needed or not

ABSTRACT

The aim of this work was to investigate is there is a need for microemulsions preservation or not. Two oil in water microemulsions with the same water/surfactant/co-surfactant [saturated polyglycolysed C8-C10 glycerides and polyglycerol isostearate], but differing in the oil phase [dipelargonate propylene glycol and isopropyl myristate] were prepared. Three different preservatives [methyl paraban, propyl paraban and sorbic acid] were added in two different concentrations to the prepared microemulsions. Challenge test [according to US Pharmacopoeia] was done for both plain microemulsion and microemulsion containing different preservatives. The results showed that there is no need for microemulsion preservation