Premium
Effect of matrix chain length on the electrophoretic mobility of large linear and branched DNA in polymer solutions
Author(s) -
Saha Sourav,
Heuer Daniel M.,
Archer Lynden A.
Publication year - 2004
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200305679
Subject(s) - electrophoresis , polymer , zeta potential , chemistry , polyethylene glycol , chain (unit) , chemical physics , materials science , chromatography , nanotechnology , physics , nanoparticle , organic chemistry , astronomy
Abstract We study the effect of matrix chain molecular weight M w and concentration c on the electrophoretic mobility μ of large linear and star‐like, branched DNA in polymer solutions. Polyethylene oxide (PEO) with narrow molecular weight distributions form the main focus of this study. For PEO concentrations ranging from one half the overlap concentration, c *, to 3 c *, the effective drag coefficient, ζ $\equiv {{\mu _0 } \over \mu } - 1$ , satisfies the following approximate scaling relationship, ζ $\sim cM_w^{0.7}$ . Here, μ 0 is the electrophoretic mobility in free solution. While the concentration dependence is consistent with predictions from the transient entanglement coupling (TEC) model, the molecular weight dependence is significantly weaker. Although a similar dependence of mobility on M w can be predicted when nonentangling collisions are the dominant source of drag, a model based on these collisions alone cannot reproduce the experimental observations. We also find that the architecture of large DNA does not affect either the concentration dependence or molecular weight dependence of the electrophoretic mobility.