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Highly Improved Electrospray Ionization-Mass Spectrometry Detection of G-Quadruplex-Folded Oligonucleotides and Their Complexes with Small Molecules.

ABSTRACT: G-quadruplexes are nucleic acids structures stabilized by physiological concentration of potassium ions. Because low stability G-quadruplexes are hardly detectable by mass spectrometry, we optimized solvent conditions: isopropanol in a triethylamine/hexafluoroisopropanol mixture highly increased G-quadruplex sensitivity with no modification of the physiological G-quadruplex conformation. G-quadruplexes/G-quadruplex-ligand complexes were also correctly detected at concentration as low as 40 nM. Detection of the physiological conformation of G4s and their complexes opens up the possibility to perform high-throughput screening of G-quadruplex ligands for the development of drug molecules effective against critical human diseases.

SUBMITTER: Scalabrin M

PROVIDER: S-EPMC5588092 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Highly Improved Electrospray Ionization-Mass Spectrometry Detection of G-Quadruplex-Folded Oligonucleotides and Their Complexes with Small Molecules.

Scalabrin Matteo M Palumbo Manlio M Richter Sara N SN

Analytical chemistry 20170824 17

G-quadruplexes are nucleic acids structures stabilized by physiological concentration of potassium ions. Because low stability G-quadruplexes are hardly detectable by mass spectrometry, we optimized solvent conditions: isopropanol in a triethylamine/hexafluoroisopropanol mixture highly increased G-quadruplex sensitivity with no modification of the physiological G-quadruplex conformation. G-quadruplexes/G-quadruplex-ligand complexes were also correctly detected at concentration as low as 40 nM. D ...[more]

PMID: 28787153

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