Long Distance Charge Transport through DNA: Quantification and Extension of the Hopping Model

Long distance charge transport through DNA occurs by a hopping mechanism. If the positive charge is injected into a guanine base, all guanines act as charge carriers. Because of the strong influence that the distance has on the charge-transfer step, DNA strands with long adenine:thymine sequences also involve adenine as charge carriers. A prerequsite for this mechanism is that the electron transfer to an adjacent adenine base is faster than the H2 O trapping reaction of the guanine radical cation. We have developed a model that can explain and qualitatively predict the product yields.