Amersham Biosciences Hoefer DALT, User Manual, Page: 44 / 70

The DALT Blotting Kit Hoefer DALT System
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Amersham Biosciences
Factors Affecting the Transfer
Sample characteristics, membrane type, gel pore size, and the transfer buffer used affect
the efficiency of macromolecule transfers. The most widely used buffer system for
transferring proteins is that of Towbin, et al. Conditions required for efficient elution
may not coincide with optimal conditions for binding. To find the optimum conditions
for transferring your sample, balance these effects:
• If the sample elution rate is slow, a longer transfer period may be required. In our
experience, high current transfers for short periods of time are superior to low
voltage transfers for longer periods.
• If sample binding is inadequate, try different buffer conditions, methanol or SDS
concentration. For a comprehensive review, see Gershoni and Palade (1983).
If the transfer buffer system is different from the electrophoresis buffer system, the gel
should be equilibrated briefly with the transfer buffer before the transfer to assure
swelling or shrinking occurs before the gel contacts the transfer membrane. If this step is
skipped, band distortion or loss of resolution could result.