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A simple dialysis device for large DNA molecules.

ABSTRACT: The potential of genomic DNA is realized when new modalities are invented that manipulate large DNAs with minimal breakage or loss of sample. Here, we describe a polydimethylsiloxane-polycarbonate membrane device to remove small molecules from a sample while retaining large DNAs. Dialysis rates dramatically change as DNA size in kb (M) increases and DNA dimensions become comparable to pore size, and chain characteristics go from rod-like to Gaussian. Consequently, we describe empirical rates of dialysis, R, as a function of M as falling into two regimes: DNAs ? 1 kb show R(M) ?e - t/? M (t = time, ?M = time constant), while DNAs ?1.65 kb slowly passage with R(M) ?M -1.68; such partitioning potentiates single-molecule imaging.

SUBMITTER: Krerowicz SJ

PROVIDER: S-EPMC6494463 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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A simple dialysis device for large DNA molecules.

Krerowicz Samuel Jw SJ Hernandez-Ortiz Juan P JP Schwartz David C DC

BioTechniques 20190201 2

The potential of genomic DNA is realized when new modalities are invented that manipulate large DNAs with minimal breakage or loss of sample. Here, we describe a polydimethylsiloxane-polycarbonate membrane device to remove small molecules from a sample while retaining large DNAs. Dialysis rates dramatically change as DNA size in kb (M) increases and DNA dimensions become comparable to pore size, and chain characteristics go from rod-like to Gaussian. Consequently, we describe empirical rates of ...[more]

PMID: 30744406

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