94 



COLLOIDS IN BIOLOGY AND MEDICINE 



An excellent apparatus l for continuous dialysis which also permits 

 a concentration of the dialyzate has been constructed by KOPAC- 

 ZEWSKI. He applies the idea of the Soxhlet extraction apparatus. 

 A collodion sac prepared as described on page 91 is placed in the tube 

 A filled with water. The dialyzate from the collodion sac may be 

 removed either through the cock C or may pass either at once or drop 

 by drop into the vessel B. If B is heated, the water vaporizes and 



Xb- 



KOPA CZEWSKtS 

 APPARATUS 



FlG. 13b. 



FIG. 14. Dialyzing filter. (L. Morochowetz.) 



passes into the two condensers and drops again through a and b into 

 the tube containing the collodion sac. Since with biological fluids 

 the temperature must remain below 50 C., the heating is done under 

 partial vacuum (reduced pressure). The tube is emptied through 

 the lateral outlet having a cock c. A concentrated dialyzate is 

 finally obtained in the vessel B. 



Where there is no running water available for dialyzing, the dialy- 

 zing filter of LEO MOROCHOWETZ may be employed. Its arrange- 

 ment may be seen in Fig. 14. The funnels may be obtained from 

 any' supply house and the parchment filters from SCHLEICHER and 

 SCHTJLL (DUREN). 



1 The apparatus may be obtained from Poulenc freres, 122 Boulevard St. 

 Germain, Paris, France. 



