SuperSignal™ Molecular Weight Protein Ladder
SuperSignal™ Molecular Weight Protein Ladder
Thermo Scientific™

SuperSignal™ Molecular Weight Protein Ladder

Thermo Scientific SuperSignal Molecular Weight Protein Ladder (20 to 150K) is a mix of eight unstained recombinant proteins with IgG-bindingRead more
Have Questions?
Catalog number 84785
Price (USD)
327.00
Each
Add to cart
Request bulk or custom format
Price (USD)
327.00
Each
Add to cart
Thermo Scientific SuperSignal Molecular Weight Protein Ladder (20 to 150K) is a mix of eight unstained recombinant proteins with IgG-binding sites for chemiluminescent, fluorescent, chromogenic or other detection systems. The protein standard is supplied in a ready-to-use format for direct loading onto gels; no need to heat, reduce, or add sample buffer prior to use.

Compare and view all other protein standards and ladders ›

The ladder’s recombinant proteins bind to the antibodies used in the western blot through the IgG binding site. The protein markers can then be visualized using appropriate substrates for enzyme-labeled antibodies or via fluorescent dye-labeled antibodies (not recommended for antibodies labeled with fluors in the 500–550 nm channel).

Two versions of the MW marker are offered. This formulation is appropriate for use with most rabbit and other non-mouse polyclonal antibodies. SuperSignal Enhanced Molecular Weight Protein ladder is formulated specifically for applications requiring mouse monoclonal antibodies and experiments where very dilute antibody concentrations are used. For example, the enhanced standard may be necessary when using a 1:50,000 (25 ng/mL) to 1:100,000 (10 ng/mL) dilution of secondary antibody.

For Research Use Only. Not for use in diagnostic procedures.
Specifications
Detection MethodUser defined detection system
Number of Markers8
Product TypeProtein Ladder
Ready to LoadYes
Size Range20 to 150 kDa
Stain TypeUnstained
Gel CompatibilityBolt™ Bis-Tris Plus Gels, Novex™ Tricine Gels, Novex™ Tris-Glycine Gels, NuPAGE™ Bis-Tris Gels, NuPAGE™ Tris-Acetate Gels, SDS-PAGE Gels
Molecular Weight (g/mol)150, 100, 80, 60, 50, 40, 30, 20 kDa
Product LineSuperSignal™
Quantity250 μL
Shipping ConditionWet Ice
System TypeWestern Blotting, SDS-PAGE
Unit SizeEach
Contents & Storage
Contents: one vial of 250 μL

Storage buffer: 62.5 mM Tris-H3PO4 (pH 7.5 at 25°C), 1 mM EDTA, 2% SDS, 10 mM DTT, 1 mM NaN3 and 33% glycerol

Storage: Upon receipt store at -20°C for long term storage, or three months at 4°C or one month at ambient

Frequently asked questions (FAQs)

With your SuperSignal Molecular Weight Protein Ladder/ SuperSignal Enhanced MW Protein Ladder, I see dye front interference in fluorescent applications. What should I do?

This is likely due to the dye-front not run off the gel or removed from the blot. We recommend running the dye front off of the gel or removing it from the blot.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

I used your SuperSignal Molecular Weight Protein Ladder and did not see any bands after western detection. What could have happened?

Here are possible causes and solutions:

- Not enough volume loaded: Load more volume onto the gel
- Incomplete or poor transfer: Optimize transfer conditions
- Secondary antibody does not recognize marker proteins: Ensure appropriate secondary is used that binds to marker proteins
- Secondary antibody not enzyme-conjugated: Ensure appropriate secondary antibody used in system
- A mouse monoclonal primary antibody was used: Use a greater volume of the ladder or use SuperSignal Enhanced Molecular Weight Protein Ladder (Cat. No. 84786) for mouse primary antibodies

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

With your SuperSignal Molecular Weight Protein Ladder and SuperSignal Enhanced MW Protein Ladder, I did not get visible band separation after western detection. What could have happened?

Here are possible causes and solutions:

- Ladder was boiled: Discard boiled aliquot.
- Too much volume of ladder used: Load less volume of the ladder.
- Concentration of antibody is too high: Optimize antibody concentration

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

I used one of your protein standards for a western transfer and noticed that some of the lower-molecular weight protein bands passed through the membrane. How can I resolve this issue?

- Decrease voltage, current or length of transfer time
- Make sure that the methanol concentration in the transfer buffer is proper; use a methanol concentration of 10-20% methanol removes the SDS from SDS-protein complexes and improves the binding of protein to the membrane.
- Make sure that the SDS concentration (if added) in the transfer buffer is proper, don't use more than 0.02-0.04% SDS. Using too much SDS can prevent binding of proteins to the membrane.
- Check the pore size of the membrane and the size of the target protein. Proteins smaller than 10 kDa will easily pass through a 0.45 µm pore size membrane. If proteins smaller than 10 kDa are of interest, it would be better to use a 0.2 µm pore size membrane.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

I used one of your protein standards for a western transfer and noticed that some of the higher-molecular weight bands transferred very poorly to the membrane. Can you offer some tips?

- Increase voltage, current or length of time for transfer
- SDS in the gel and in the SDS-protein complexes promotes elution of the protein from the gels but inhibits binding of the protein to membranes. This inhibition is higher for nitrocellulose than for PVDF. For proteins that are difficult to elute from the gel such as large molecular weight proteins, a small amount of SDS may be added to the transfer buffer to improve transfer. We recommend pre-equilibrating the gel in 2X Transfer buffer (without methanol) containing 0.02-0.04% SDS for 10 minutes before assembling the sandwich and then transferring using 1X transfer buffer containing 10% methanol and 0.01%SDS.
- Methanol removes the SDS from SDS-protein complexes and improves the binding of protein to the membrane, but has some negative effects on the gel itself, leading to a decrease in transfer efficiency. It may cause a reduction in pore size, precipitation of some proteins, and some basic proteins to become positively charged or neutral. Make sure that the methanol concentration in the transfer buffer is not more than 10-20% and that high-quality, analytical grade methanol is used.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

View all SuperSignal™ Molecular Weight Protein Ladder FAQs