The number of samples in each film is related to the gluing system used. The most common model is 10- 15 sample loading holes, one hole is a marker, and the rest can measure n- 1 sample. I used 25 holes at most.
Several different protein can be measured on the membrane, which is related to the molecular weight of the target protein. If the bands between protein can be completely separated, the antibody specificity is strong and there is no confusion, it is possible to detect two or three kinds of protein.