Membranes and Filter Papers for Western Blotting

PVDF (polyvinylidene difluoride) and nitrocellulose membranes are available in different pore sizes and dimensions for different application needs. A protein's properties (i.e., charge, hydrophobicity, etc.) affect its ability to bind to membrane surfaces, so finding the optimal membrane may require experimenting with your specific protein on different membranes. Protein transfer is easier and more convenient with our pre-cut, pre-assembled western blot membrane/filter paper sandwiches that perfectly fit your gels. Alternatively, assemble your own using our nitrocellulose and PVDF membranes and filter paper.

Nitrocellulose membranes are a popular matrix used in protein blotting because of their high protein-binding affinity, compatibility with a variety of detection methods (chemiluminescence, chromogenic, and fluorescence), and the ability to immobilize proteins, glycoproteins, or nucleic acids. Protein immobilization is thought to occur by hydrophobic interactions, and high salt and low methanol concentrations help improve protein immobilization to the membrane during electrophoretic transfer, especially for proteins with higher molecular weights. Nitrocellulose membranes are not optimal for electrophoretic transfer of nucleic acids, as the high salt concentrations that are required for efficient binding will effectively elute some or all of the charged nucleic acid fragments.

Polyvinylidene difluoride (PVDF) membrane is ideal for western blotting applications as well as for amino acid analysis and protein sequencing of small amounts of proteins (as little as 10 pmoles). In addition, PVDF membranes can be used, stripped and reprobed without a loss of sensitivity or increased background.

PVDF membranes are highly hydrophobic and must be pre-wetted with methanol or ethanol prior to submersion in transfer buffer. PVDF membranes have a high binding affinity for proteins and nucleic acids and may be used for applications such as western, Southern, northern, and dot blots; binding likely occurs via dipole and hydrophobic interactions. PVDF membranes offer a better retention of adsorbed proteins than other supports because of the greater hydrophobicity. PVDF is also less brittle than nitrocellulose.

iBlot and iBlot 2 Transfer Stacks are consumable stacks with integrated PVDF or nitrocellulose transfer membranes for dry blotting of proteins. Each transfer stack contains a copper coated electrode and appropriate cathode and anode buffers in the gel matrix to allow fast, reliable transfer of proteins.

Nitrocellulose membrane

The nitrocellulose membrane (0.2 µm pore size) in this stack is composed of 100% pure nitrocellulose to provide high-quality transfer. The membrane is compatible with commonly used detection methods such as staining, immunodetection, fluorescence, or radiolabeling. The proteins bind to the membrane due to hydrophobic and electrostatic interactions. The protein binding capacity is 209 µg/cm2.

PVDF membranes

The PVDF membrane (0.2 µm pore size, low fluorescence) in this stack has higher binding capacity than nitrocellulose. The PVDF membrane is preactivated and ready for use without any pretreatment with alcohols. The membrane is compatible with commonly used detection methods such as staining, immunodetection, fluorescence, or radiolabeling. The proteins bind to the membrane due to hydrophobic interactions. The protein binding capacity is 240 µg/cm2.

Transfer stack sizes

The mini size (8 cm x 8 cm) can be used for all Invitrogen precast and handcast mini gels (or other mini gel types). The regular size (13 cm x 8.3 cm) can be used for all Invitrogen midi gels (or other midi gel types), or two Invitrogen mini gels (or other mini gel types), and E-PAGE 48 or 96 gels.

The Invitrogen Power Blotter Select Transfer Stacks are used to transfer proteins using the Power Blotter System. They are disposable, pre-assembled stacks that come with an integrated preactivated PVDF or nitrocellulose transfer membrane for dry blotting of proteins from polyacrylamide gels. Each Power Blotter Select Transfer Stack contains filter paper, membrane, and the appropriate cathode and anode buffers incorporated into a solid gel matrix to allow fast, reliable transfer of proteins.

Select stack PVDF membranes

The PVDF membrane (0.45 µm pore size, low fluorescence) has higher binding capacity than nitrocellulose. The membrane is compatible with commonly used detection methods such as staining, immunodetection, and fluorescence. The proteins bind to the membrane through hydrophobic interactions. This membrane has lower background levels and increased sensitivity for fluorescent probing than regular PVDF or nitrocellulose membranes.

Select stack Nitrocellulose membrane

The nitrocellulose membrane (0.2 µm pore size) in the stack is composed of 100% pure nitrocellulose to provide high-quality transfer. The membrane is compatible with commonly used detection methods such as staining, chemiluminescence, and fluorescence. The proteins bind to the membrane through hydrophobic and electrostatic interactions. The protein binding capacity is 209 µg/cm2.

Invitrogen Power Blotter Pre-cut Membranes and Filters are designed for the transfer of proteins using the Power Blotter System. The pre-cut membranes and filters include 20 sheets of polyvinylidene difluoride (PVDF) or nitrocellulose and 80 sheets of absorbent blotting paper (0.85 mm thickness). Power Blotter Pre-cut Membranes and Filters combined with Power Blotter 1-Step Transfer Buffer allow for high-efficiency semi-dry transfer of proteins in less than 10 minutes.

Western blotting filter papers are pre-cut cotton sheets for wet or semi-dry, passive or electrophoretic transfer of proteins from polyacrylamide gels (SDS-PAGE) to PVDF, nitrocellulose, or other membranes. Sheets of blotting paper are necessary components of transfer sandwiches and cassettes that typically must be assembled for various kinds of protein or nucleic acid, gel-to-membrane, transfer protocols. High-quality western blotting filter papers are available as standard-thickness and extra-thick sheets that are pre-cut for convenience with mini gels and midi gels. Choose a paper with the thickness and dimensions appropriate for specific gel sizes and device platforms or cassettes.

Nitrocellulose membranes are a popular matrix used in protein blotting because of their high protein-binding affinity, compatibility with a variety of detection methods (chemiluminescence, chromogenic, and fluorescence), and the ability to immobilize proteins, glycoproteins, or nucleic acids. Protein immobilization is thought to occur by hydrophobic interactions, and high salt and low methanol concentrations help improve protein immobilization to the membrane during electrophoretic transfer, especially for proteins with higher molecular weights. Nitrocellulose membranes are not optimal for electrophoretic transfer of nucleic acids, as the high salt concentrations that are required for efficient binding will effectively elute some or all of the charged nucleic acid fragments.

Polyvinylidene difluoride (PVDF) membrane is ideal for western blotting applications as well as for amino acid analysis and protein sequencing of small amounts of proteins (as little as 10 pmoles). In addition, PVDF membranes can be used, stripped and reprobed without a loss of sensitivity or increased background.

PVDF membranes are highly hydrophobic and must be pre-wetted with methanol or ethanol prior to submersion in transfer buffer. PVDF membranes have a high binding affinity for proteins and nucleic acids and may be used for applications such as western, Southern, northern, and dot blots; binding likely occurs via dipole and hydrophobic interactions. PVDF membranes offer a better retention of adsorbed proteins than other supports because of the greater hydrophobicity. PVDF is also less brittle than nitrocellulose.

iBlot and iBlot 2 Transfer Stacks are consumable stacks with integrated PVDF or nitrocellulose transfer membranes for dry blotting of proteins. Each transfer stack contains a copper coated electrode and appropriate cathode and anode buffers in the gel matrix to allow fast, reliable transfer of proteins.

Nitrocellulose membrane

The nitrocellulose membrane (0.2 µm pore size) in this stack is composed of 100% pure nitrocellulose to provide high-quality transfer. The membrane is compatible with commonly used detection methods such as staining, immunodetection, fluorescence, or radiolabeling. The proteins bind to the membrane due to hydrophobic and electrostatic interactions. The protein binding capacity is 209 µg/cm2.

PVDF membranes

The PVDF membrane (0.2 µm pore size, low fluorescence) in this stack has higher binding capacity than nitrocellulose. The PVDF membrane is preactivated and ready for use without any pretreatment with alcohols. The membrane is compatible with commonly used detection methods such as staining, immunodetection, fluorescence, or radiolabeling. The proteins bind to the membrane due to hydrophobic interactions. The protein binding capacity is 240 µg/cm2.

Transfer stack sizes

The mini size (8 cm x 8 cm) can be used for all Invitrogen precast and handcast mini gels (or other mini gel types). The regular size (13 cm x 8.3 cm) can be used for all Invitrogen midi gels (or other midi gel types), or two Invitrogen mini gels (or other mini gel types), and E-PAGE 48 or 96 gels.

The Invitrogen Power Blotter Select Transfer Stacks are used to transfer proteins using the Power Blotter System. They are disposable, pre-assembled stacks that come with an integrated preactivated PVDF or nitrocellulose transfer membrane for dry blotting of proteins from polyacrylamide gels. Each Power Blotter Select Transfer Stack contains filter paper, membrane, and the appropriate cathode and anode buffers incorporated into a solid gel matrix to allow fast, reliable transfer of proteins.

Select stack PVDF membranes

The PVDF membrane (0.45 µm pore size, low fluorescence) has higher binding capacity than nitrocellulose. The membrane is compatible with commonly used detection methods such as staining, immunodetection, and fluorescence. The proteins bind to the membrane through hydrophobic interactions. This membrane has lower background levels and increased sensitivity for fluorescent probing than regular PVDF or nitrocellulose membranes.

Select stack Nitrocellulose membrane

The nitrocellulose membrane (0.2 µm pore size) in the stack is composed of 100% pure nitrocellulose to provide high-quality transfer. The membrane is compatible with commonly used detection methods such as staining, chemiluminescence, and fluorescence. The proteins bind to the membrane through hydrophobic and electrostatic interactions. The protein binding capacity is 209 µg/cm2.

Invitrogen Power Blotter Pre-cut Membranes and Filters are designed for the transfer of proteins using the Power Blotter System. The pre-cut membranes and filters include 20 sheets of polyvinylidene difluoride (PVDF) or nitrocellulose and 80 sheets of absorbent blotting paper (0.85 mm thickness). Power Blotter Pre-cut Membranes and Filters combined with Power Blotter 1-Step Transfer Buffer allow for high-efficiency semi-dry transfer of proteins in less than 10 minutes.

Western blotting filter papers are pre-cut cotton sheets for wet or semi-dry, passive or electrophoretic transfer of proteins from polyacrylamide gels (SDS-PAGE) to PVDF, nitrocellulose, or other membranes. Sheets of blotting paper are necessary components of transfer sandwiches and cassettes that typically must be assembled for various kinds of protein or nucleic acid, gel-to-membrane, transfer protocols. High-quality western blotting filter papers are available as standard-thickness and extra-thick sheets that are pre-cut for convenience with mini gels and midi gels. Choose a paper with the thickness and dimensions appropriate for specific gel sizes and device platforms or cassettes.