- Why strip and reprobe Western blot membranes
- Reprobing strategy selection based on protein abundance and antibody affinity
- Stripping methods and protocol options
- Practical recommendation
- How to verify complete antibody removal before reprobing
- Step-by-step workflow for reprobing membranes
- Troubleshooting common stripping and reprobing problems
- Choosing membranes and reagents for successful reprobing
- Alternative methods of detecting additional proteins
- Cytiva products that support stripping and reprobing
Maximize sample efficiency and detect multiple proteins using proven stripping methods and reprobing strategies.
Stripping and reprobing a Western blot membrane allows you to reuse the same blot to detect additional proteins by removing bound antibodies while retaining immobilized proteins (Fig. 1)
This approach conserves sample, reduces reagent cost, and enables direct comparison of related targets under identical experimental conditions. Successful reprobing depends on protein abundance, antibody affinity, membrane choice, and stripping method selection.
Fig 1. Stripping and reprobing allows you to detect multiple proteins from a single Western blot membrane.
Why strip and reprobe Western blot membranes
Western blotting combines protein separation by gel electrophoresis with antibody-based detection to identify and quantify protein targets. Once you master the basic technique as outlined in our simple, step-by-step guide, you’ll quickly discover that a single blot contains far more information than the first detection reveals. Techniques like stripping and reprobing allow you to return to the same membrane, remove the bound antibodies and probe it again for additional proteins.
This approach is especially valuable when:
- Sample quantity is limited (precious clinical specimens or rare cell types)
- Internal loading controls must be measured on the same membrane
- Related proteins need to be compared under identical conditions
- Protein targets have similar molecular weights and risk overlap
When applied strategically, stripping and reprobing help maximize biological insight while reducing time, reagent use, and sample consumption.
When Western blot membrane reuse makes sense
There are several experimental situations in which reprobing a membrane provides clear, scientific, and practical advantages:
Limited sample quantity
When working with precious clinical samples, rare cell types, or low‑abundance proteins, you may only have enough material for a single gel. Reprobing allows you to extract multiple data points from that one sample. For example, if you are studying phosphorylation in patient‑derived tumor tissue, you can probe for total protein, strip the membrane, and reprobe for phosphorylated isoforms without consuming more sample.
Normalization and loading controls
Normalization is essential for reliable interpretation of protein expression differences. After detecting your protein of interest, stripping the blot allows reprobing for loading controls such as β‑actin, GAPDH, α‑tubulin, or total protein stains. Both detections occur on the same membrane, and the normalization is more accurate than comparisons taken from separate gels.
Study of related targets
Pathway analyses often require sequential probing for multiple proteins, such as kinase cascades, receptor complexes, or transcription factor families. Reprobing ensures that each target is assessed under identical transfer, blocking, and exposure conditions, improving the internal consistency of your results.
Proteins of similar molecular weights
When two proteins migrate close together on a gel, detecting them simultaneously can cause band overlap or ambiguity. Stripping and reprobing allows you to detect each protein independently while keeping the same physical lane positions for comparison.
Benefits for limited samples and overlapping protein sizes
The primary benefit of stripping and reprobing is data maximization. Each membrane becomes a reusable platform that yields multiple insights per sample. This reuse reduces reagent costs, saves time, and conserves precious material.
For proteins that comigrate, such as isoforms or similarly sized family members, reprobing also improves specificity. You can detect each target independently, eliminating signal interference while preserving the original lane pattern. This strategy supports clearer interpretation, especially in experiments where subtle changes in expression are critical.
Reprobing strategy selection based on protein abundance and antibody affinity
Choosing which antibody to apply first is an important experimental decision. Protein abundance and antibody affinity work together to influence signal intensity and stripping success. Low-abundance targets are more vulnerable to signal loss, and low-affinity antibodies are less tolerant of repeated stripping.
Here’s how these factors guide strategy:
- Low‑abundance targets are detected first, because their weak signal may be partially lost after stripping.
- Low‑affinity antibodies are used first, because harsher conditions later may make them less effective.
- High‑abundance proteins and high‑affinity antibodies are more forgiving, so they can withstand the second detection cycle.
Strategy 1: Similar abundance, similar affinity—detect either first
When both proteins are present at comparable levels and the antibodies bind with similar strength, neither target is at a disadvantage during detection or after stripping. Therefore, the stripping process is unlikely to compromise one target more than the other, giving you flexibility in which to probe first. In practice, this scenario often occurs when studying proteins within the same family or structural class. Because stripping efficiency is unlikely to bias results, you can focus instead on workflow convenience, such as probing the target of primary interest first.
Strategy 2: similar abundance, unequal affinity—detect with the lower affinity antibody first
Lower‑affinity antibodies produce weaker or less stable signals. If used after stripping, these antibodies may perform even more poorly because the membrane surface becomes slightly altered after each stripping cycle. Detecting the low‑affinity target first ensures it is measured under optimal conditions with a freshly blocked membrane and no chemical stress. After stripping, the higher‑affinity antibody, being more robust, can still generate strong signal even if the membrane has undergone harsher treatments. This approach is especially important when quantifying subtle changes in expression where faint bands could be misinterpreted as biological variation rather than technical limitation.
Strategy 3: unequal abundance, equal affinity—detect the low abundance protein first
Low‑abundance proteins are inherently more difficult to detect, so they must be probed under the best possible conditions. Even slight protein loss during stripping can turn a faint but detectable band into a signal that disappears entirely. By probing the low‑abundance target first, you protect that measurement from the cumulative effects of reagent exposure, heat, or detergent that accompany stripping. High‑abundance targets, on the other hand, typically generate strong signals even with partial protein loss, making them better suited for second‑round detection.
Strategy 4: unequal abundance, unequal affinity—detect the low‑abundance, low‑affinity combination first
This scenario presents the highest risk of losing signal, because both biological and antibody‑driven factors work against detection. A low‑abundance target probed with a low‑affinity antibody should always be prioritized before any stripping occurs. This approach ensures that the weakest signal is captured under the most favorable conditions. After stripping, the remaining target—high abundance and/or high antibody affinity—is far more resilient and likely to give a clear, interpretable signal even if the membrane has been stressed by the stripping process. This strategy teaches how to triage targets based on combined biochemical constraints rather than treating all proteins equally.
Table 1. Decision guide for choosing a strategy
| Choosing a reprobing strategy | Protein abundance | ||
| Similar | Unequal | ||
| Antibody affinity | Similar | Strategy 1 | Strategy 3 |
| Unequal | Strategy 2 | Strategy 4 | |
Stripping methods and protocol options
Stripping removes antibodies without removing immobilized proteins. Selecting the appropriate method requires balancing stripping efficiency against protein preservation.
Table 2. Comparing common stripping methods
| Method | Harshness | Best use case | Key cautions |
| Low-pH buffers | Mild | Low-affinity antibodies, fragile proteins | May not fully remove strong antibodies |
| Heat + SDS + β-mercaptoethanol | High | High-affinity antibodies, abundant targets | Risk of protein loss |
| High-pH / high-salt | Moderate–high | Persistent antibody residues | Monitor exposure time carefully |
Practical recommendation
Start with the mildest method likely to work and increase stringency only if residual signal persists.
Heat and detergent stripping for high affinity antibodies
High‑affinity antibody–antigen interactions form tight, stable complexes, so they require more aggressive conditions to fully dissociate. Using SDS together with β‑mercaptoethanol and moderate heat (typically 50°C to 70°C) provides a multilayered disruption: SDS breaks hydrophobic interactions and denatures antibody structure, while β‑mercaptoethanol reduces disulfide bonds that stabilize antibody conformations. Heat accelerates these chemical effects, ensuring that even strongly bound primary antibodies are efficiently removed. This method is particularly useful after probing for robust and resilient targets—such as cytoskeletal proteins (e.g., actin or tubulin) or abundant metabolic enzymes—because these proteins tend to remain strongly attached to the membrane despite harsh treatment.
However, this approach requires careful balancing. If stripping conditions are too mild, residual antibody may linger and produce faint ghost bands in the next detection. But if conditions are too harsh, membrane‑bound proteins may elute, distort, or partially degrade, compromising any subsequent probing. To help find the right balance, you can test stripping conditions using dot blots or by cutting the original membrane into smaller strips. Both these techniques allow rapid condition‑screening without consuming rare or limited samples.
Mild, low pH stripping for gentle antibody removal
Low pH buffers provide a more controlled and selective means of disrupting antibody–antigen interactions. At acidic pH (typically around pH 2 to 2.5), antibody binding regions lose their native ionic and hydrogen bonding interactions, causing antibodies to dissociate without severely disrupting the immobilized protein. As a result, low pH stripping is ideal for sensitive or low affinity antibody systems where harsher reagents might remove or denature the target protein. For example, transcription factors, signaling intermediates, and conformationally unstable proteins often respond better to acidic stripping because their epitopes remain intact for subsequent probing.
This gentler method also benefits fluorescent detection workflows. Many fluorophores degrade under heat or strong detergents, reducing their usefulness in later steps. Mild stripping helps preserve membrane bound proteins and prevents cumulative damage that could raise background or reduce signal quality during reprobing.
High pH and high salt stripping as alternative methods
High‑pH, NaOH‑based stripping solutions and high‑salt SDS buffers offer additional flexibility when dealing with persistent antibody complexes or detection chemistries that leave behind stubborn residues. At very high pH, antibodies rapidly unfold, releasing them from the membrane. Similarly, high salt concentrations disrupt ionic interactions that stabilize antibody binding. These methods are particularly useful when strong chemiluminescent enhancers or highly stable antibody conjugates leave faint residual signal that interferes with the next detection cycle. While effective, these conditions should be monitored closely because prolonged exposure can weaken membrane structure or dissolve loosely bound proteins.
How to verify complete antibody removal before reprobing
Ensuring that the first set of antibodies has been fully removed is a critical quality-control step and is one is often overlooked. Even a trace amount of remaining primary antibody can bind secondary antibody during the next detection, creating misleading background bands or false positives. Performing a secondary antibody‑only incubation after stripping is the simplest and most reliable check for complete antibody removal. If no signal appears, stripping was successful. If signal persists, the membrane should be stripped again using stronger conditions. This quick verification step reinforces good experimental discipline and ensures the integrity of the final data.
Step-by-step workflow for reprobing membranes
Although the stripping conditions and reagents used will vary, the basic workflow for stripping and reprobing membranes stays the same. After recording the results from the initial detection, you’ll follow the steps outlined below.
Prepare the membrane after initial detection
- Remove detection reagents: Discard any substrate or detection solution from the initial detection.
- Wash the membrane: Rinse the membrane three times for 5 min each in Tris-buffered saline with 0.1% Tween-20 (TBST) to remove residual reagents.
Strip, wash, and reblock the membrane
- Strip the membrane: Select a stripping method from those described above based on the antibody’s strength and agitate gently during incubation.
- Wash thoroughly: After stripping, wash the membrane three to five times in TBST to remove residual reagents.
- Verify stripping efficiency: Incubate with secondary antibody only and perform a quick detection. No signal should appear.
- Optional reblock: If needed, block the membrane again using your standard blocking buffer (e.g., 5% nonfat dry milk or BSA in TBST) for 30 to 60 min at room temperature.
Reprobe with new primary and secondary antibodies
- Incubate with new primary antibody: Incubate the membrane with the new primary antibody either overnight at 4°C for best sensitivity or for 1 to 2 h at room temperature for faster results.
- Wash: Rinse the membrane three times for 5 to 10 min each in TBST.
- Incubate with new secondary antibody: Incubate the membrane with the new secondary antibody for 1 h at room temperature.
- Wash and detect: Do a final wash (three to five times in TBST), then proceed with your chosen detection method (chemiluminescence, fluorescence, etc.).
Troubleshooting common stripping and reprobing problems
Troubleshooting helps you think systematically about causes and effects. It reinforces that stripping is a balance of chemistry, protein stability, and experimental planning. By identifying the underlying mechanism, chemical harshness, incomplete washing, or physical membrane fragility, you can troubleshoot confidently rather than guessing.
Some common problems and their solutions are described below.
Residual signal from incomplete stripping
- Cause: Antibodies from the first probing were not fully removed.
- Possible solutions: - Use a harsher stripping buffer (e.g., SDS + β-mercaptoethanol at 50°C to 55°C).
- Extend stripping time or repeat the process.
Loss of protein and weak signal after multiple strips
- Cause: Harsh stripping conditions or repeated cycles can remove or denature immobilized proteins.
- Possible solutions: - Limit stripping to one to two cycles per membrane.
- Start with mild stripping buffers whenever possible.
- If multiple targets are needed, consider multiplexing or running additional gels instead of excessive stripping.
Increased background on reprobed blots
- Cause: Residual stripping chemicals or incomplete blocking can lead to nonspecific binding
- Possible solutions: - Wash thoroughly after stripping (three to five times in TBST).
- Reblock the membrane for 30 to 60 min before applying new antibodies.
- Use fresh blocking buffer and ensure proper antibody dilutions.
Physical membrane damage
- Cause: High temperatures, harsh chemicals, or excessive handling during stripping can damage membranes.
- Possible solutions: - Handle membranes gently with clean forceps.
- Avoid prolonged exposure to harsh stripping buffers.
- Use polyvinylidene fluoride (PVDF) membranes for better durability compared to nitrocellulose membranes.
- Keep stripping times as short as possible while still effective.
Choosing membranes and reagents for successful reprobing
Successful multiple protein detection starts before you perform your Western blot. Think ahead about what you hope to accomplish as you choose membranes and reagents.
PVDF vs nitrocellulose membranes for repeated use
PVDF membranes are generally preferred for reprobing because they offer higher protein-binding capacity and superior durability. They can withstand harsh stripping conditions without tearing or losing proteins, making them ideal for multiple cycles. Nitrocellulose membranes, on the other hand, provide excellent signal-to-noise ratio for single-use blots but are more fragile and prone to damage during repeated stripping. For experiments that require multiple rounds of probing, PVDF is the recommended choice.
Reinforced membranes suitable for multiple cycles
Some manufacturers produce reinforced PVDF membranes specifically designed for repeated stripping and reprobing. These membranes maintain structural integrity under high temperatures and harsh chemical conditions, reducing the risk of tearing during handling. When planning workflows that involve multiple cycles, check product specifications for labels indicating multiuse or high durability.
Compatible detection reagents for chemiluminescence and fluorescence
Chemiluminescent detection works well for reprobing but requires thorough stripping to eliminate residual horseradish peroxidase (HRP) signal. If performing chemiluminescent detection, be sure to use substrates that do not permanently modify the membrane because strong enhancers can leave background interference.
Fluorescent detection is better for multiplexing because it allows the detection of multiple targets without stripping. If stripping is necessary, ensure that fluorophores are completely removed or select antibodies with different emission spectra to avoid overlap.
Whether using chemiluminescent or fluorescent detection, choose reagents that are compatible with your stripping buffer and do not compromise the sensitivity of subsequent detections.
Alternative methods of detecting additional proteins
In some cases, you can detect additional proteins without stripping the membrane.
Sequential labeling with ECL detection
When using enhanced chemiluminescence (ECL) detection for a Western blot, a sequential labeling method is available for quick detection of a second protein on a single membrane. To do this, labeling and detection of the first protein is performed as normal using ECL. The HRP is then inactivated (quenched) using hydrogen peroxide (H2O2) and the membrane is washed. The second protein can then be labeled with a different antibody for detection without any interference.
Usually, a 30 min incubation with 15% H2O2 is sufficient to fully quench the signal from an HRP-labeled protein. However, the amount of HRP present does influence the concentration of H2O2 necessary, as well as the incubation time.
Multiplex detection
To avoid stripping and reprobing altogether, multifluorescence (multiplex) detection can be used to detect multiple proteins on the same membrane. In this technique, secondary antibodies labeled with fluorophores enable simultaneous detection of more than one protein.
Cytiva products that support stripping and reprobing
Cytiva has many products to support you throughout your Western blot protocol. If your procedure includes stripping and reprobing, we have some products that are particularly well-suited for these steps.
Amersham™ PVDF and nitrocellulose membranes for reprobing
Amersham™ Hybond P membranes are PVDF membranes favored for Western blot membrane reuse because they combine high mechanical strength with strong protein-binding capacity. Their hydrophobic surface and small pore sizes (commonly 0.2 or 0.45 µm) allow firm attachment of proteins even after harsh washing and stripping procedures. Therefore, the membranes tolerate aggressive stripping buffers without physical damage or significant protein loss.
Standard nitrocellulose is fragile when subjected to repeated handling and drying. However, Amersham™ Protran Supported nitrocellulose membranes are reinforced with a polyester backing that greatly enhances its mechanical integrity. This support layer prevents tearing and brittleness, enabling repeated stripping and reprobing while maintaining low background and consistent protein binding.
Amersham™ ECL, ECL start, and ECL prime detection reagents
Both Amersham™ ECL Western blotting detection reagent and the cost-effective Amersham™ ECL start Western blotting detection reagent are designed for routine detection of high- to medium-abundance proteins and produce clean, sharp bands suitable for multiple rounds of probing. These reagents provide reliable signal with minimal background and are compatible with PVDF and supported nitrocellulose membranes commonly used for reprobing workflows. Their signals are strong enough for accurate detection yet not so chemically aggressive as to harm membrane-bound proteins during downstream stripping.
If you need a stronger signal intensity, consider using Amersham™ ECL prime Western blotting detection reagent. It delivers a highly stable and long-lasting signal, lasting more than 24 h, which makes it a optimal choice when planning repeated exposures or allowing flexibility in imaging time after initial detection. This durability also means that even after stripping, signal remnants are less likely to interfere because ECL prime's substrate does not permanently alter the membrane. Moreover, its enhanced signal intensity allows you to use high dilutions of primary and secondary antibodies, reducing background and preserving precious reagents—great for iterative probing.
Amersham™ blocking agent and ECL prime blocking reagent
Amersham™ ECL blocking agent efficiently covers nonspecific binding sites without interfering with HRP activity. This clean blocking yields a high signal-to-noise ratio, which is essential when stripping and reprobing because any residual signal or high background can compromise later detections.
Amersham™ ECL Prime blocking reagent is optimized not only for standard chemiluminescence but also for fluorescence-based Western blotting. Its formulation is compatible with both PVDF and supported nitrocellulose membranes. By improving blocking efficiency, it helps reduce background during both initial probing and subsequent reprobings. Moreover, its clean background facilitates confident stripping checks, such as secondary-only incubations, which confirm removal of antibodies before reprobing.
Conclusion
Stripping and reprobing Western blot membranes is a powerful technique for detecting multiple proteins from a single blot when applied strategically. By prioritizing low-abundance targets, selecting appropriate stripping methods, verifying antibody removal, and limiting the number of cycles, researchers can maximize data quality while conserving valuable samples.
FAQs
How many times can a Western blot membrane be reprobed?
Most membranes can be stripped and reprobed one to two times without significant protein loss. Additional cycles increase the risk of weak signal and background artifacts.
When should I avoid stripping and reprobing?
Avoid reprobing for extremely low-abundance targets, after multiple harsh stripping cycles, or when fluorescence multiplexing can achieve the same goal without membrane reuse.
Which membrane is optimal for reprobing?
PVDF membranes are generally preferred due to their durability and protein retention under stripping conditions.