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Updated: Feb 7, 2026

Detection of Glycosaminoglycans by Polyacrylamide Gel Electrophoresis and Silver Staining
Published on: February 25, 2021
DNA ladders can be used to size polyphosphate resolved by polyacrylamide gel electrophoresis
Stephanie A Smith1, Yan Wang2, James H Morrissey1
1Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
Abstract:
PAGE is often used to resolve inorganic polyphosphates (polyP), but unfortunately polyP size ladders are not commercially available. Since several dyes that are commonly used to detect nucleic acids in gels also stain polyP, we examined the utility of commercially available DNA size ladders for estimating polyP polymer lengths by gel electrophoresis. Narrow size fractions of polyP were prepared and their polymer lengths were quantified using NMR. Commercially available DNA ladders and these polyP fractions were then subjected to PAGE to determine the relationship between migration of DNA vs polyP, which was found to be: log10 (dsDNA length in bp) = 1.66 × log10 (polyP length in phosphate units) - 1.97. This relationship between DNA and polyP size held for a variety of different polyacrylamide concentrations, indicating that DNA size ladders can readily be employed to estimate polyP polymer lengths by PAGE.
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