Affinity electrophoresis with three methylcellulose batches. The three batches have similar degree of substitution (1.76, 1.78 and 1.80 and denoted accordingly) however their substitution pattern differs. MC 1.76 is more homogeneously substituted while MC 1.78 and MC 1.80 have substitution patterns that are more heterogeneous. Three CBMs and a negative control (G-4) were run on native acrylamide gels containing one of each methylcellulose batch. CBM4-2 is more retained in the gels containing MC 1.78 or MC 1.80 compared to MC 1.76. A-6 and X-2 L110F are less discriminating and are retained in all gels containing methylcellulose. None of the CBMs were retained in the control gel containing no methylcellulose.