Temperature Effects on Threshold Counterion Concentration to Induce Aggregation of fd Virus

الأصل · EN

We seek to determine the mechanism of like-charge attraction by measuring the temperature dependence of critical divalent counterion concentration (Cc) for the aggregation of fd viruses. We find that an increase in temperature causes Cc to decrease, primarily due to a decrease in the dielectric constant (ε) of the solvent. At a constant ε, Cc is found to increase as the temperature increases. The effects of T and ε on Cc can be combined to that of one parameter: Bjerrum length (lB). Cc decreases exponentially as lB increases, suggesting that entropic effect of counterions plays an important role at the onset of bundle formation.