Bio-Rad Sequi-Blo PVDF Membrane User Manual

Sequi-Blot PVDF

Membrane

for Pr otein Sequencing

Instruction

Manual

Bio-Rad Laboratories, 2000 Alfred Nobel Dr., Hercules, CA 94547

LIT240 Rev C

Table of Contents

Section 1 Introduction .............................1

Section 2 Membrane Wetting .................3

Section 3 Dot Blotting .............................5

Section 4 Electrophoretic Blotting

Section 5 Amino Acid Analysis by

Section 6 Protein Dectection .................16

Section 7 Technical Assistance .............18

Section 8 References ..............................19

Section 9 Product Information .............20

for Protein Sequencing ..........7

Hydrolysis of Membrane

Bound Proteins ......................13

Section 1
Introduction

The hydrophobicity of PVDF (polyvinyli­dene difluoride) membrane makes it an ideal
support for binding proteins in electrophoretic
and dot blotting applications. Proteins are tight­ly bound, and are quantitatively retained during
exposure to acidic, basic, or organic solvents.
Resistance to acidic and organic solvents which
would dissolve nitrocellulose or nylon mem­branes makes PVDF membrane an excellent
support for amino-terminal protein sequenc-

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ing.

The unique manufacturing process used
for Bio-Rad’s Sequi-Blot PVDF membrane
insures higher protein binding capacity than
other commercially available PVDF products.
Higher capacity increases the likelihood of
sequencing proteins of interest, which makes
Sequi-Blot PVDF membrane the best choice for

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sequence analysis of blotted proteins and pep­tides.

For use of PVDF membrane as an
immunoblotting support for western blot detec­tion, Bio-Rad offers Immun-Blot

®

PVDF mem­brane which features lower signal to
background results in this application than
Sequi-Blot membrane. However, it does not
exhibit the same high protein binding capacity,
so Sequi-Blot PVDF membrane is the best one
to use for protein sequencing.

Section 2
Membrane Wetting

Sequi-Blot PVDF membrane can be used
as a direct replacement for the membrane cur­rently being used in your sequencing protocol.
No changes are required in the procedure, but
the special steps given below are required to
prepare the membrane for blotting. The
hydrophobicity of the PVDF membrane makes
it impossible to wet the membrane with aque­ous solutions. Methanol or an alternative organ­ic solvent is required to pre-wet the membrane
prior to equilibration in transfer buffer. After
equilibration, the membrane can be used in a
semi-dry, tank, or capillary blotting system
with any acidic or basic blotting buffer.

Note: Always handle membranes using gloves or
forceps to prevent contamination.

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