Most Western blot users visualize transferred proteins using stains, such as Ponceau S or Coomassie® Blue. However, users of PVDF membrane have the opportunity to assess transfer efficiency using transillumination. Areas of PVDF coated with transferred protein are capable of wetting out in 20% methanol while the surrounding areas of PVDF are not. In the areas where the PVDF wets, it becomes optically transparent, allowing visualization of protein bands using backlighting and photographic archiving.
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