Si. Pather et al., A COMPARISON OF 2 QUALITY ASSESSMENT METHODS FOR EMULSIONS, Journal of pharmaceutical and biomedical analysis, 13(10), 1995, pp. 1283-1289
A common method of assessing the quality of emulsions is to evaluate t
he size distribution of the globules of the internal phase. The primar
y aim of this work is to compare the sensitivity of this test to an al
ternative method. The sizes of the globules of two emulsions, an oral
emulsion and a total parenteral nutrition (TPN) emulsion, were determi
ned using a light microscope. Globule size analyses were performed upo
n preparation and during storage of the emulsions. Using a computer pr
ogram specially developed for this study, the recorded diameters were
placed into size groups and the volumes of each of the measured globul
es was determined. For each size group, the total volume of all the gl
obules within the group and the volume percentage of the oil phase rep
resented by the group were calculated. The volume distribution of the
internal phase across the size groups was found to predict emulsion in
stability better than the globule number distribution and thus is a be
tter determinant of emulsion quality. This technique may have general
application in the evaluation or TPN emulsions and other spheres, such
as liposomes.