Please use this identifier to cite or link to this item:
Title: Condensation Transition in DNA-Polyaminoamide Dendrimer Fibers Studied Using Optical Tweezers
Author: Ritort Farran, Fèlix
Mihardja, S.
Smith, S.B.
Bustamante, C.J.
Keywords: Condensació
Issue Date: 22-Mar-2006
Publisher: American Physical Society
Abstract: When mixed together, DNA and polyaminoamide dendrimers form fibers that condense into a compact structure. We use optical tweezers to pull condensed fibers and investigate the decondensation transition by measuring force-extension curves (FECs). A characteristic force plateau (around 10 pN) and hysteresis between the pulling and relaxation cycles are observed for different dendrimer sizes, indicating the existence of a first-order transition between two phases (condensed and extended) of the fiber. Upon salt variation FECs change noticeably confirming that electrostatic forces drive the condensation transition. We propose a simple model for the decondensing transition that qualitatively reproduces the FECs and which is confirmed by atomic force microscopy images.
Note: Reproducció del document publicat a:
It is part of: Physical Review Letters, 2006, vol. 96, num. 11, p. 118301
Related resource:
ISSN: 0031-9007
Appears in Collections:Articles publicats en revistes (Física de la Matèria Condensada)

Files in This Item:
File Description SizeFormat 
602514.pdf863.85 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.