Nitrocellulose Membrane for Western Blot

What is a nitrocellulose membrane?

Nitrocellulose membranes are one of the top matrices used in protein blotting in Western Blotting, offering significant advantages over simple filter paper in terms of protein retention and signal clarity. They have high protein-binding capacity, strong affinity for proteins of varying protein size, compatibility with a variety of protein detection methods, and the ability to immobilize proteins, glycoproteins, or nucleic acids. This variety of detection methods include chemiluminescence, chromogenic, and fluorescence. It is proven to produce excellent signal-to-noise results when used for amino acid analysis, protein sequencing and western, northern, and Southern blotting.

What is a western blot?

Western blotting (also called Protein Immunoblotting) is an analytical technique used to detect specific proteins in the given sample. A thorough understanding of the western blot principle is crucial to successfully applying this method and accurately interpreting the results, while proper western blot sample preparation plays a vital role in ensuring the reliability and sensitivity of the detection process.

It uses SDS-polyacrylamide gel electrophoresis (SDS-PAGE) to separate various proteins contained in the sample. The separated proteins are then transferred through protein transfer onto Western blot membranes, where they are stained with antibodies specific to the target protein for subsequent protein detection. Expression details of the target proteins in the given cells or tissue homogenate can then be obtained through analyzing the location and intensity of the specific reaction during western blot detection.

Western blotting analysis can detect target protein as low as 1 ng due to the high resolution of the gel electrophoresis and strong specificity and high sensitivity of the immunoassay. This method is widely applied in molecular biology, biochemistry, immunogenetics and other molecular biology disciplines for various experiments. Researchers looking to streamline this traditional workflow can explore our In-Cell Western Blot Service, which skips the membrane transfer and enables direct, quantitative protein analysis in cultured cells.

How do proteins bind to nitrocellulose membranes?

Proteins bind to nitrocellulose blotting membranes primarily through a combination of electrostatic and hydrophobic interactions, which together define the protein binding capacity of the membrane— a property that traditional filter paper lacks. These interactions are enhanced by high salt and low methanol concentrations within the transfer buffer, which facilitate protein immobilization during electrophoretic transfer—particularly for proteins of larger protein size.

While effective for protein transfer, nitrocellulose membranes are less suited for nucleic acid applications such as RNA transfers, which typically require optimized conditions for retention and stability. The salt concentrations needed to support protein binding can interfere with nucleic acid retention by disrupting their charge-based interactions. Additionally, nitrocellulose is soluble in organic solvents like methanol and acetone, so solvent exposure must be minimized to preserve membrane integrity.

Despite these challenges, nitrocellulose membranes can still yield reliable results for nucleic acid detection when experimental conditions are carefully controlled.

Options for western blot transfer membranes

Membrane selection is a critical step in Western blotting. The three main types of transfer membranes are nitrocellulose, polyvinylidene fluoride (PVDF), and nylon (polyamide). The pros and cons and differences are described in the following table:

PVDF Nitrocellulose Nylon
Protein size Better with high molecular weight proteins Better with mid to low molecular weight proteins (< 20 kDa) Better with nucleic acids
Binding capacity 100 – 200 μg/cm2 80 – 100 μg/cm2 > 400 μg/cm2
Background noise Slightly low Very low High
Strip and re-probe Performs well when treated with a suitable stripping buffer Possible but may lose sensitivity Performs well
Mechanical strength High Brittle when dry High
Solvent resistance Strong Weak weak
Pre-treatment Wet with methanol Wet with buffer Wet with buffer
Pore size 0.2 μm and 0.45 μm options 0.2 μm and 0.45 μm options 0.45 μm

One of the greatest benefits of using the nitrocellulose membrane over the other membranes is its balance of protein binding capacity across a wide range of protein size, along with very low background noise. The background is the darkening of the blot as the protein travels through the membrane. A high background noise equates to a highly darkened blot, which means it is difficult to distinguish specific bands. For tips on minimizing western blot high background, review our troubleshooting guide. The very low background noise seen with the nitrocellulose membranes helps to ensure the experiment can be run with minimal difficulty interpreting the results.

If you are still deciding between PVDF and nitrocellulose based on target size, background tolerance, reprobing needs, or handling preference, this guide on which membrane to choose for Western blot provides a more practical side-by-side workflow for membrane selection.

Where to Purchase Nitrocellulose Membranes

Nitrocellulose membrane for western blot product image

Boster Bio offers premium nitrocellulose membranes for western blot applications helping researchers simplify membrane selection by providing high-quality options for different experimental needs. We specializes in manufacturing primary antibodies for WB, IHC, and ICC/IF as well as producing high quality ELISA and reagent kits. Our lab runs hundreds of WB every week for our internal production quality control, and we use the reagents and kits we manufacture ourselves for our ELISA kits and IHC- and WB-validated antibodies, so we ensure all our extraction kits, buffers, controls, solutions, etc. will help you obtain clean and specific results for accurate localization and identification of antigens.

We provide nitrocellulose membrane for western blot transfer with both pore 0.2 μm (Catalog# AR0135-02) and pore 0.45 μm (Catalog# AR0135-04) options. Boster’s nitrocellulose membranes can be used for a wide range of protein molecular weights and nucleic acids > 500 base pairs in size, and they perform reliably with common transfer buffer formulations. Each ordered pack contains 20 sheets measuring 9 cm x 10 cm in size. They can remain stable for one year when stored at room temperature. The products are high quality, pure 100% nitrocellulose membranes with a high surface area and excellent uniformity. The variety optimizes for peptide applications with the 0.2 μm pore size and protein applications with the 0.45 μm pore size.

How to Use Nitrocellulose Membranes in Western Blots

There are five main steps involved in the western blot workflow, described as follows:

  • Transfer Process

    : Proteins are moved from within the gel onto the nitrocellulose or PVDF western blot membranes using an optimized transfer buffer. This ensures efficient protein transfer with minimal loss of protein activity. Without pre-activation, proteins combine with the membrane based on hydrophobic interaction. Therefore, there is only a slight effect on the protein activities.

  • Blocking Step

    : In a western blot, it is important to block the unreacted sites on the membrane to reduce the amount of nonspecific binding of proteins during subsequent steps in the assay using inert protein or nonionic detergent. The chosen blocking buffers should block all unreacted sites, should not replace target protein on the membrane, not bind epitope on the target protein, and not cross react with antibody or detection reagents.

  • Primary Antibody Incubation

    : After blocking, a primary antibody specific to the target protein is incubated with the nitrocellulose membrane. This allows the primary antibody to bind to target the protein on the membrane.

  • Secondary Antibody Incubation

    : After rinsing the membrane to remove unbound primary antibody, the membrane is exposed to a specific enzyme-conjugated secondary antibody. The chosen secondary antibody will bind to the primary antibody, which has already reacted with the target protein.

  • Western Blotting Analysis

    : After color development, the pattern of the separated proteins is imprinted onto a film or captured by Western Blot gel imager. This allows for comparison of the band position to the protein ladder, thereby estimating the size of the protein.

References

  • Kurien, B. T. and Scofield, R. H. (2015). Western blotting: an introduction. Methods Mol Biol, 1312, 17-30.
  • Xiang, Y., Zheng, Y., Liu, S. et al. (2021). Comparison of the sensitivity of Western blotting between PVDF and NC membranes. Sci Rep, 11, 12022.
  • Xu, J., Sun, H., Huang, G. et al. (2019). A fixation method for the optimisation of western blotting. Sci Rep, 9, 6649.

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