Processes triggered in guanine quadruplexes by direct absorption of UV radiation: From fundamental studies toward optoelectronic biosensors

The primary processes induced in guanine quadruplexes (GQs) by direct UV absorption have been studied by time-resolved spectroscopy, associated with computational methods. The present  review highlights the outcomes of these fundamental studies that could contribute to the development of optoelectronic biosensors using GQ intrinsic signals (label-free, dye-free), explored recently by a few groups. It explains how certain structural factors, intervening during the excited state r elaxation, affect both fluorescence emission and low-energy photoionization generating charge carriers. Accordingly, these features can be tuned so that to optimize the desired signal. AbstractGuanine quadruplexes (GQs) are four-stranded DNA/RNA structures exhibiting an important polymorphism. During the past two decades, their study by time-resolved spectroscopy, from femtoseconds to milliseconds, associated to computational methods, shed light on the primary processes occurring when they absorb UV radiation. Quite recently, their utilization in label-free and dye-free biosensors was explored by a few groups. In view of such developments, this review discusses the outcomes of the fundamental studies that could contribute to the design of future optoelectronic biosensors using fluorescence or charge carriers stemming directly from GQs, without mediation of other molecules, as it is the currently the case. It explains how the excited state relaxation influences both the fluorescence intensity and the ...

Source: Photochemistry and Photobiology - June 27, 2023 Category: Science Authors: Dimitra Markovitsi Tags: INVITED REVIEW Source Type: research