title: ssDNA degradation along capillary electrophoresis process using a Tris buffer.
abstract: Tris-Acetate buffer is currently used in the selection and the characterization of ssDNA by capillary electrophoresis (CE). By applying high voltage, the migration of ionic species into the capillary generates a current that induces water electrolysis. This phenomenon is followed by the modification of the pH and the production of Tris derivatives. By injecting ten times by capillary electrophoresis ssDNA (50 nM), the whole oligonucleotide was degraded. In this paper, we will show that the Tris buffer in the running vials is modified along the electrophoretic process by electrochemical reactions. We also observed that the composition of the metal ions changes in the running buffer vials. This phenomenon, never described in CE, is important for fluorescent ssDNA analysis using Tris buffer. The oligonucleotides are degraded by electrochemically synthesized species (present in the running Tris vials) until it disappears, even if the separation buffer in the capillary is clean. To address these issues, we propose to use a sodium phosphate buffer that we demonstrate to be electrochemically inactive.
authors.affiliation: Laboratoire des IMRCP, UMR 5623, Université de Toulouse, Université Paul Sabatier, Toulouse, France.|CNRS, Institut de Pharmacologie et de BiologieStructurale, UMR 5089, Université de Toulouse, France.|Picometrics Technologies, Labège, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Ric
authors.affiliation: Laboratoire des IMRCP, UMR 5623, Université de Toulouse, Université Paul Sabatier, Toulouse, France.
authors.forename: Varravaddheay
authors.initials: V
authors.lastname: Ong-Meang
authors.affiliation: Laboratoire des IMRCP, UMR 5623, Université de Toulouse, Université Paul Sabatier, Toulouse, France.
authors.forename: Verena
authors.initials: V
authors.lastname: Poinsot
authors.affiliation: Service commun de spectrométrie de masse, institut de chimie de Toulouse, Université de Toulouse, Université Paul Sabatier, Toulouse, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Martins-Froment
authors.affiliation: Laboratoire de Génie Chimique, UMR 5503, Université de Toulouse, Université Paul Sabatier, Toulouse, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Chauvet
authors.affiliation: Picometrics Technologies, Labège, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Boutonnet
authors.affiliation: Picometrics Technologies, Labège, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Ginot
authors.affiliation: CNRS, Institut de Pharmacologie et de BiologieStructurale, UMR 5089, Université de Toulouse, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Ecochard
authors.affiliation: CNRS, Institut de Pharmacologie et de BiologieStructurale, UMR 5089, Université de Toulouse, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Paquereau
authors.affiliation: Laboratoire des IMRCP, UMR 5623, Université de Toulouse, Université Paul Sabatier, Toulouse, France.
authors.forename: François
authors.initials: F
authors.lastname: Couderc
mesh_terms: D002021:Buffers; D002851:Chromatography, High Pressure Liquid; D004277:DNA, Single-Stranded / Q000032:analysis* / Q000737:chemistry; D055664:Electrochemical Techniques; D019075:Electrophoresis, Capillary / Q000379:methods*; D004591:Electrophoresis, Polyacrylamide Gel; D005452:Fluoresceins / Q000737:chemistry; D005453:Fluorescence; D013058:Mass Spectrometry; D009841:Oligonucleotides / Q000032:analysis*
chemical_list: D002021:Buffers; D004277:DNA, Single-Stranded; D005452:Fluoresceins; D009841:Oligonucleotides; C024098:6-carboxyfluorescein
keywords: Biomolecules; Capillary electrophoresis; Oligonucleotides; Tris-Acetate buffer; ssDNA degradation