Protein Standards & Ladders - UK (2024)

FAQs

Are all protein ladders the same? ›

Common Types of Protein Ladder

They can have either all proteins prestained with one color, two or more proteins prestained in different colors, or all proteins prestained with different colors. Prestained protein ladders have three highly-intensified colored reference bands of 25 kDa, 50 kDa, and 75 kDa (kilodaltons).

Mix gently, but thoroughly, to ensure that the solution is hom*ogeneous. 3. Load the following volumes of the ladder on SDS-polyacrylamide gel: – 5 μL per well for mini gel, – 10 μL per well for large gel. Use the same volumes for Western blotting.

Protein ladders, also known as protein markers or protein standards, are used to help estimate the size of proteins separated during electrophoresis. They serve as points of reference because they contain mixtures of highly purified proteins with known molecular weights and characteristics.

Prestained Protein Standards. What are the storage conditions and shelf life for the PageRuler™ Prestained Protein Ladder and PageRuler™ Plus Prestained Protein Ladder? We recommend storing these ladders at –20 degrees C where they are stable for a year. They are stable for up to 3 months at 4 degrees C.

The difference between an unstained protein ladder and a prestained protein ladder is that unstained ladders require additional staining post electrophoresis. Prestained ladders are prestained with dyes for better visualization and tracking during electrophoresis.

Make sure that the protein standard was not heated/boiled prior to loading on the gel. Our protein standards are ready to load and we do not recommend heating/boiling them as this may cause degradation of proteins in the standard.

Loading too much protein leads to signal saturation in western blots, yet too little produces weak signals. This protocol describes an assay development experiment to determine the appropriate protein load for target and control detection prior to performing the actual western blot experiment.

We recommend sample loads between 1 and 10 μg of protein per well. Optimize primary and secondary antibody dilutions. In most cases, this means reducing the total amount of antibody used (higher dilutions). This will limit the amount of HRP in the system to prevent saturation of signal.

For a standard electrophoresis system, we recommend loading 0.5 µg (20 µl) of the Fast DNA Ladder on the agarose gel. For a fast electrophoresis system (5 to 30 minutes separation), follow the system's manufacturer recommendations: 5 to 20 µl load. A dilution of the ladder may be required.

The most important factor in choosing a DNA ladder is the expected size of the DNA bands in your experiment. You want to make sure that the range of the DNA ladder, from its smallest to its largest fragment, includes the expected size of the DNA fragments you are testing (Figure 1).

What is the purpose of a prestained protein ladder? ›

Prestained broad and high molecular weight protein ladders

Prestained molecular weight standards are ideal to monitor the progression of the gel electrophoresis run and to estimate protein transfer efficiency. Available in blue and multicolor options, they are compatible with all Invitrogen SDS-PAGE gels.

All prestained recombinant ladders include three high-intensity reference bands (25, 50, and 75 kD). For size determination on western blots, depending on the visualization method being used, the protein ladder can be unstained, prestained, or with a Strep-tag sequence.

Load the following volumes of the ladder on an SDS-polyacrylamide gel: – 5 μL per well for mini gel, – 10 μL per well for large gel. Use the same volumes for Western blotting. The loading volumes listed above are recommended for gels with a thickness of 0.75-1.0 mm.

We recommend storing the BenchMark™ Unstained Protein Ladder at –20 degrees C. It may also be stored at 4 degrees C. The ladder is stable for six months when properly stored.

b) Type I – These ladders have a duty rating of 250 pounds. Type I ladders are manufactured for heavy-duty use. c) Type II – These ladders have a duty rating of 225 pounds. Type II ladders are approved for medium-duty use.

As a result of all of these interactions, each type of protein has a particular three-dimensional structure, which is determined by the order of the amino acids in its chain. The final folded structure, or conformation, adopted by any polypeptide chain is generally the one in which the free energy is minimized.

Not all Protein is Equal

Protein sources react differently in the body based on unique absorption rates and differing levels of both essential and non-essential amino acids. The unique amino acid composition of proteins affects how the body is able to utilize them for growth, recovery & maintenance.

Both the Little Giant and Gorilla are essentially the same ladder with the latter being a Chinese copy of the original.