Unit

UNIT 5.3 Size Fractionation Using Sucrose Gradients

  1. John H. Weis (sucrose gradients and partial digestion)1,
  2. Thomas Quertermous (complete digestion)2

Published Online: 1 MAY 2001

DOI: 10.1002/0471142727.mb0503s00

Current Protocols in Molecular Biology

Current Protocols in Molecular Biology

How to Cite

Weis, J. H. and Quertermous, T. 2001. Size Fractionation Using Sucrose Gradients. Current Protocols in Molecular Biology. 00:II:5.3:5.3.1–5.3.8.

Author Information

  1. 1

    Harvard Medical School, Boston, Massachusetts

  2. 2

    Massachusetts General Hospital, Boston, Massachusetts

Publication History

  1. Published Online: 1 MAY 2001
  2. Published Print: OCT 1987

Abstract

DNA fragments migrate through a linear sucrose gradient at a rate that is dependent on their size. This procedure described in this unit provides good resolution for DNA fragments 5 to 60 kb in size, and sucrose gradients are also useful for purification of bacteriophage l vector arms. Partially digested genomic DNA can be fractionated for the production of cosmid or bacteriophage libraries and completely digested DNA can be fractionated for subgenomic DNA libraries. Protocols are provided in this unit for both partial and complete enzyme digestion of genomic DNA.