Monitoring the Stability of an Emulsion by High-Frequency Spectroscopy

Laser ionization/time-of-flight mass spectrometry for the direct analysis of emulsions

“…Other methods for evaluating the stability of an emulsion should be used and compared against the results obtained in the present study. Fortunately, the present system can easily be combined with several other conventional methods, 26,27 since the capillary was simply inserted into the container of an emulsion with no other interference.…”

“…To date, several techniques have been used to evaluate emulsions: spectrometry, light scattering, and small X-ray scattering. [23][24][25][26][27][28][29] To the best of our knowledge, an online mass spectrometric and stability evaluation approach of emulsions has not yet been accomplished. Normally, appropriate pretreatments such as drying or matrix addition are performed before the mass analysis.…”

Time-Profile Measurement of an Emulsion Using Multiphoton Ionization Time-of-Flight Mass Spectrometry in Combination with a Microscope

“…Therefore, it is not only the stability of emulsions, but also their evaluation methods, that are quite important for use both in fundamental study and in practical application. Several analytical methods for small droplets and/or emulsions have been reported: microscopy, 16 fluorescence correlation spectroscopy, 17 fluorescence lifetime imaging, 18 magnetophoretic velocimetry, 19,20 high-frequency spectroscopy, 21 and small-angle X-ray diffraction. 22 However, direct analysis of the constituents and their concentrations is quite difficult, and these factors influence the stability of emulsions.…”