Amylum solubile

With Other sols electrolytes may give similar effects. After a strong decrease at very low concentrations, to be discussed below, at higher concentrations ( ]s—V o)Mo may increase, which must be interpreted as increase of solvation. Fig. 15 gives an example, referring to amylum solubile and a number of potassium salts. The interpretation, that these changes in spec, viscosity are really related to changes in solvation seems fortified by the order of the curves, which is that of the so-called lyotropic series of the anions CNS > J > NO3 > Br > Cl > SO4... 

Reversal of charge with hexol nitrate of negatively charged macromolecular sols — first met with in the case of amylum solubile (see p. 207 Fig. 19) — has been shown to occur very generally. In general they do not lend themselves to a vis-... 

If such a colloid and such salts are chosen, that form favourable combinations for viscosimetric investigation, — favourable here meaning that no flocculation or coacervation accompanies the reversal of charge — then it may be expected that, similar to the combination amylum solubile + hexol nitrate minima in the( / — o )/>/ curves must also occur. 

Still another example may be quoted to illustrate the quite different nature of salting out and of flocculations with hexol nitrate and other salts with polyvalent ions in small concentrations amylum solubile sols are readily salted out e.g., with certain sulphates, whereas its sols do not flocculate with the named 6, 5, or 4 valent complex cations. 

Nucleate > arabinate ) agar > amylum solubile, glycogen. 

The same holds for the combinations of these two proteins with the above mentioned series nucleate to amylum solubile. Thus we can in principle set up a similar series also for the positive complex components, in which series, if combined with the same negative component, the intensity of the complex relations decreases from left to right. 

Coacervates of all kinds of types, provided the colloid belongs to the hydrophilic type, wet a glass surface and spread over it when they settle on it from the equilibrium liquid. We have already mentioned (p. 339, note 3) that covering the glass surface with a dried layer of amylum solubile prevents this spread as a result of which such starched microscope slides form an indispensible aid in the microscopic study of the colloid morphology of these coacervates. 

It is prepared by treating starch with 7.5% aqueous hydrochloric acid or 15% sulfuric acid over several days at r.t. The acid-free washed and dried product dissolves easily in boiling water to give a perfectly clear, stable fluid at a concentation of 2%. It is termed soluble starch or amylum solubile . 

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