Antigen size considerations

In general, the affinity of the antibodies selected is proportional to the size of the library, with Kd s ranging from 10 6/7 for the smaller libraries [2,3] to 10-9 for the larger ones [1,4], a finding which is in line with theoretical considerations [12]. Antibodies selected from immunized libraries tend to have higher affinities for the antigen used for immunization from an equivalent library size. 

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