Coacervate deformation

The transitional shapes are again readily deformable under the cover glass by pushing it backwards and forwards under pressure and they can also unite to an apparent homogeneous coacervate layer by centrifuging (up to a certain limit). 

If one introduces a coacervated system, consisting of coacervate drops suspended in their equilibrium liquid, into a d.c. electric field three phenomena can be observed simultaneously 1. electrophoresis 2. deformation 3. disintegration phenomena... 

The deformation of coacervate drops also occurring in a d.c. field, can be observed undisturbed in an ax. field (for example of frequency 50) since electrophoresis and disintegration phenomena are hereby excluded. 

Fig. 7. Deformation of complex coacervate drops in an a.c. electric field.

The similarity also appears to continue in all kinds of other properties. Thus the coacervate drops obtained from gum arabic and hexol nitrate placed in an electric field also exhibit the deformation and disintegration phenomena previously discussed (see p. 347-348) and as concerns the latter these are with positively charged drops again the minor image of those with negatively charged drops. 

With sufficiently large coacervate drops the deformation and disintegration phenomena in an electric field could be observed in their typical forms. 

Fig. 12. Behavour of liquid inclusions in complex coacervate drops in a d.c. electric field (schematic). A initial state, B final stage of the relative displacement, in which the organic liquid drop protrudes from the surface of the coacervate drop deformed by the, Buchner effect (see p. 347). Simultaneous vacuolation phenomena etc. in the complex coacervate drops (p. 347 and 452) are omitted from the scheme.

In this stage d the wall of the hollow sphere is obviously already perforated but as a result of the very high viscosity of the G -h N + a coacervate this is deformed only very slowly. Naturally it must eventually deform since a perforated spherical shell consisting of liquid cannot be stable from the point of view of the free energy. The morphogical path along which such a perforated coacervate object finally deforms... 

Nevertheless this deformation is here obviously a sluggish process so that in between the wetting equilibria begin to establish themselves. The inner wall of the G + N + a coacervate shell is wetted better by the G + A + n coacervate than by the vacuole liquid. Therefore this much less viscous coacervate flows inwards through the perforation hole and displaces the vacuole liquid from the wall which is thereby partly pressed outwards (Fig. 25d). 

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