<P> Since the membrane has been chosen for its ability to bind protein and as both antibodies and the target are proteins , steps must be taken to prevent the interactions between the membrane and the antibody used for detection of the target protein . Blocking of non-specific binding is achieved by placing the membrane in a dilute solution of protein -- typically 3 -- 5 % bovine serum albumin ( BSA ) or non-fat dry milk ( both are inexpensive ) in tris - buffered saline ( TBS ) or I - Block , with a minute percentage ( 0.1 % ) of detergent such as Tween 20 or Triton X-100 . Although non-fat dry milk is preferred due to its availability , an appropriate blocking solution is needed as not all proteins in milk are compatible with all the detection bands . The protein in the dilute solution attaches to the membrane in all places where the target proteins have not attached . Thus , when the antibody is added , there is no room on the membrane for it to attach other than on the binding sites of the specific target protein . This reduces background in the final product of the western blot , leading to clearer results , and eliminates false positives . </P>
<P> Since the membrane has been chosen for its ability to bind protein and as both antibodies and the target are proteins , steps must be taken to prevent the interactions between the membrane and the antibody used for detection of the target protein . Blocking of non-specific binding is achieved by placing the membrane in a dilute solution of protein -- typically 3 -- 5 % bovine serum albumin ( BSA ) or non-fat dry milk ( both are inexpensive ) in tris - buffered saline ( TBS ) or I - Block , with a minute percentage ( 0.1 % ) of detergent such as Tween 20 or Triton X-100 . Although non-fat dry milk is preferred due to its availability , an appropriate blocking solution is needed as not all proteins in milk are compatible with all the detection bands . The protein in the dilute solution attaches to the membrane in all places where the target proteins have not attached . Thus , when the antibody is added , there is no room on the membrane for it to attach other than on the binding sites of the specific target protein . This reduces background in the final product of the western blot , leading to clearer results , and eliminates false positives . </P>
in western blotting the non-specific sites on the membrane can be blocked by
in western blotting the non-specific sites on the membrane can be blocked by
a dilute solution of protein -- typically 3 -- 5 % bovine serum albumin ( BSA ) or non-fat dry milk ( both are inexpensive ) in tris - buffered saline ( TBS ) or I - Block , with a minute percentage ( 0.1 % ) of detergent such as Tween 20 or Triton X-100
a dilute solution of protein -- typically 3 -- 5 % bovine serum albumin ( BSA ) or non-fat dry milk ( both are inexpensive ) in tris - buffered saline ( TBS ) or I - Block , with a minute percentage ( 0.1 % ) of detergent such as Tween 20 or Triton X-100