Stability assessment of dispersions and emulsions

Details Stability assessment of dispersions and emulsions Stability assessment of dispersions and emulsions

2006-12-19

2006-12-19

Wallenhorst, Maureen M. (Department: 1743)

Chemistry: analytical and immunological testing

Clotting or clotting factor level tests

C436S164000, C436S176000, C422S073000, C422S068100, C073S053010, C073S061430, C073S061480, C073S061710, C073S064410, C073S064430

Reexamination Certificate

active

07150996

ABSTRACT:
A method and apparatus for determining the stability of dispersions and emulsions accelerates the onset of significant particle agglomeration in a sample by stressing the sample by reducing the height of the interparticle potential energy barrier between the particles. This is achieved by adding one or more of three stress factors: changing the pH of the sample to reduce the surface charge on the particles; adding an adsorbing electrolyte so that ions of the appropriate charge are adsorbed onto the surfaces of the particles to reduce the net charge on the particles; and applying a monovalent, divalent, or trivalent salt to partially screen electrostatic repulsions between the charged particles. In a preferred embodiment, the increase in agglomeration is detected with single particle detection, such as SPOS, to generate a PSD from which a figure of merit is derived. Another embodiment detects turbidity or light scattering to generate a value X indicative of the extent of agglomeration.

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