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Which of the following best defines Western blotting (immunoblotting)?
Which description correctly explains how SDS-PAGE causes proteins to separate primarily by size?
On an SDS-PAGE gel a ladder shows 100 kDa protein migrating 2.0 cm from the well and 25 kDa protein migrating 8.0 cm. An unknown protein migrates 5.0 cm. Using log10(MW) linear interpolation between the two ladder points, estimate the molecular weight of the unknown protein. Show calculations.
Design an experiment using Western blot to distinguish between total human IgG, IgM, and IgA responses to an antigen on the membrane while minimizing cross-reactivity between detection antibodies. Which combination of reagents and steps is the most appropriate?
A diagnostic Western blot for HIV requires reactivity to at least two of several defined bands to be considered positive. If a patient's blot shows faint bands at p24 and gp41 barely above background, how should a lab interpret the faintness of bands, and what follow-up is most appropriate?