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HomeGel ElectrophoresisSelecting Markers and Ladders for Gel Electrophoresis

Selecting DNA, RNA, and PCR Fragment Markers and Ladders for Gel Electrophoresis

Standard DNA Markers
Digested DNA Markers
PCR Markers
RNA Markers

DNA and RNA Markers for size determination

DNA and RNA size markers contain a mixture of DNA (or RNA) fragments of known length, making them suitable for estimating the fragment length of concurrently run samples. Markers and ladders stain well with ethidium bromide and other common nucleic acid stains for visualization after gel electrophoresis.

We offer a variety of markers for nucleic acid size determination of samples separated by various gel electrophoresis methods.

markers-and-ladders-selection-guide

Figure 1.

Standard DNA Markers

Agarose gel electrophoresis requires standard DNA markers. DNA ladders are available in a convenient, ready-to-use versions.

Digested DNA Markers

Agarose gel electrophoresis for size determination of DNA digest fragments benefits from markers prepared as fragments of digested DNA. The gel bands for DNA digest markers are illustrated below.

PCR Markers

Agarose or polyacrylamide gel electrophoresis for size determination of PCR fragments benefits from markers designed for use with PCR fragments.

RNA Markers

RNA electrophoresis requires markers prepared from RNA. The Transcript RNA Marker contains nine RNA transcripts. The ladder is diluted in gel loading buffer and then loaded in a single lane on an agarose gel. Markers are suitable for size determination of small RNA using native or denaturing agarose gel electrophoresis. The Transcript RNA Markers 0.2-10 kb has been used as a molecular weight marker for northern blot hybridization. The Transcript RNA Marker is provided in a gel-loading solution with 10 mM Tris-HCl (pH 8.0), with 1.0 mM EDTA and contains nine defined RNA transcripts. For optimal resolution, the recommended agarose gel concentration is 1.0%.

Materials Table
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