SEPARATION OF OLIGOSACCHARIDES WITH GEL FILTRATION 347 



TABLE I 



In collaboration with Dr. Bengt Nygard an X-ray diffraction analysis 

 of the cellodextrins was made in a Guinier camera with Cu K^ radiation, 

 and an exposure time of i hr. The films obtained were analyzed photo- 

 metrically and the values for sin'^^ calculated. In Table II the number of 



definitely identified reflections and the sin-^ values are given for the three 

 strongest and most significant ones. The reflexions obtained from cello- 

 hexaose were diffuse indicating heterogeneity. Likewise the molecular 

 weight was lower than the theoretical value, whereas the tendency for the 

 other oligosaccharides was towards somewhat too high values. 



Discussion 



Preliminary experiments to separate cellodextrins were made with a 

 50-100 mesh sieve fraction of Sephadex. A high flow rate could be used 

 and an experiment in a 2500 ml. column was made in 7 hr. The analysis 

 of the eflluent fractions gave a smooth curve. Paper chromatography of the 

 material in the fractions showed, however, that the fractions contained 

 only two and sometimes three components. 



The results were so encouraging that it was decided to try more 

 efficient columns in order to obtain a complete separation of the oligosac- 

 charides. Earlier investigations had shown that the best way to increase 

 the efficiency was to use smaller dextran gel particles, and consequently 



