Controlled Pore Glass-based oligonucleotide affinity support: towards High Throughput Screening methods for the identification of conformation-selective G-quadruplex ligands Chiara Platella a , Domenica Musumeci a , Angela Arciello a , Filippo Doria b , Mauro Freccero b , Antonio Randazzo c , Jussara Amato c , Bruno Pagano c , Daniela Montesarchio a, * a Department of Chemical Sciences, University of Naples Federico II, via Cintia 21, 80126, Naples, Italy b Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy c Department of Pharmacy, University of Naples Federico II, via D. Montesano 49, 80131, Naples, Italy highlights graphical abstract  A functionalized Controlled Pore Glass incorporating hexaethylene glycol was developed.  G-quadruplex-forming oligonucleo- tides were synthesized on this novel solid support.  These oligonucleotide-bound sup- ports allowed affinity chromatography-based screenings.  Putative G-quadruplex ligands were analyzed by a rapid, easy spectro- photometric test.  Fluorescence confocal microscopy discriminated G-quadruplex vs. duplex DNA on CPG. article info Article history: Received 6 March 2018 Received in revised form 27 April 2018 Accepted 30 April 2018 Available online xxx Keywords: Controlled Pore Glass G-quadruplex Hairpin duplex Affinity chromatography Conformation-selective ligand Confocal microscopy abstract Target selectivity is one of the main challenges in the search for small molecules able to act as effective and non-toxic anticancer and/or antiviral drugs. To achieve this goal, handy, rapid and reliable High Throughput Screening methodologies are needed. We here describe a novel functionalization for the solid phase synthesis of oligonucleotides on Controlled Pore Glass, including a flexible hexaethylene glycol spacer linking the first nucleoside through the nucleobase via a covalent bond stable to the final deprotection step. This allowed us preparing fully deprotected oligonucleotides still covalently attached to their supports. In detail, on this support we performed both the on-line synthesis of different sec- ondary structure-forming oligonucleotides and the affinity chromatography-based screenings of conformation-selective G-quadruplex ligands. By using a fluorescent core-extended naphthalene diimide with different emitting response upon binding to sequences folding into G-quadruplexes of different topologies, we have been able to discriminate not only G-quadruplex vs. duplex DNA structures, but also different G-quadruplex conformations on the glass beads by confocal microscopy. © 2018 Elsevier B.V. All rights reserved. * Corresponding author. E-mail address: daniela.montesarchio@unina.it (D. Montesarchio). Contents lists available at ScienceDirect Analytica Chimica Acta journal homepage: www.elsevier.com/locate/aca https://doi.org/10.1016/j.aca.2018.04.071 0003-2670/© 2018 Elsevier B.V. All rights reserved. Analytica Chimica Acta xxx (2018) 1e9 Please cite this article in press as: C. Platella, et al., Controlled Pore Glass-based oligonucleotide affinity support: towards High Throughput Screening methods for the identification of conformation-selective G-quadruplex ligands, Analytica Chimica Acta (2018), https://doi.org/ 10.1016/j.aca.2018.04.071