Journal of Cluster Science

, Volume 14, Issue 2, pp 115–122

MgCl2 Enhances Cluster Formation by Nanoscale Toroidal DNA Condensates



Multivalent cations can cause DNA to condense from its extended state in solution into high-density toroid-shaped particles. Developing methods to control the size and size distribution of DNA toroids is an important goal for the development of artificial gene delivery systems. Here we demonstrate that changes in salt conditions, prior to condensation by multivalent cations, can significantly affect DNA condensation. Specifically, millimolar concentrations of MgCl2 are shown to cause the formation of toroid clusters, whereas NaCl at the same ionic strength does not.

gene delivery DNA packaging psi-DNA 


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Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  1. 1.Georgia Institute of TechnologyAtlanta

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