Confocal Laser Scanning Microscopy (CSLM) was also carried
out to follow the residual oil during the preparation of the particles,
as shown in Fig. 5. The observations led to the conclusion that
although traces of oil and surfactant may be present in the dispersions,
those were not associated to the particles. Upon centrifugation,
those detached patches would locate in the supernatant,
excluding them from the sample analysed by NMR. This might
partly explains the low values of oil content found with NMR spectroscopy.
It was concluded that three washing steps were sufficient
to remove the majority of the oil phase originally surrounding the
particles.