122 MARTIN G. LARRABEE AND PAUL HOROWICZ 



Dr. Morales: If it is merely hydrogen bond you ought to be able to take 

 this out. 



Dr. Fischer: I would be able if I would desorb the wool for perhaps three 

 or four days. You can take off, i.e. desorb every substance; it is only a question 

 of time, temperature, pH. etc. There are certain substances which are so firmly 

 bound to wool that to desorb them would considerably alter the chemical as 

 well as physico-chemical structure of the wool protein. 



Dr. Morales: We are talking about hydrogen bonding, though; this is 

 something that you could easily reverse. 



Dr. Fischer: I say, mainly of hydrogen bonds but I do not say that these 

 are the only bonds involved. 



Dr. Blum: It seems to me that you do this at 90°C. first and then you 

 wash it at room temperature. I think Dr. Morales is correct in saying that he 

 would expect a pretty rapid change if it was just hydrogen binding. But, on 

 the other hand, in the original experiment you bind this enormous quantity 

 at 90°, in which situation, the bond structure of the keratin is quite stabilized 

 and then you reduce it to 25°. You may bind up your substances by much more 

 semi-covalence as you may have multiple entrapped, enclosed molecules. You 

 might easily account for this large quantity and yet you would also be able 

 to explain why it didn't come off. 



Dr. Fischer: Let me give you one experimental detail which refers to both 

 of your remarks. 



If you determine the absolute affinity of a compound for wool, there is no 

 rinsing involved at the end of the procedure; these absolute values are 5-6 

 times higher than those obtained by the weight increase method where rinsing 

 is applied at the end of the procedure. 



