title: Thermal pretreatments of superficially porous silica particles for high-performance liquid chromatography: Surface control, structural characterization and chromatographic evaluation.
abstract: This study reports the impact of thermal pretreatment between 400 and 1100°C on superficially porous silica particles (e.g. core-shell, fused-core; here abbreviated as SPP silica). The different thermally pretreated SPP silica (400°C, 900°C and 1100°C) were chemically bonded with an octadecyl chain under microwave irradiation. The bare SPP silica, thermally untreated and pretreated, as well as the chemically bonded phases (CBPs) were fully characterized by elemental analysis, diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), and solid state cross polarization magic angle spinning (CP-MAS) (29)Si NMR. The chromatographic properties of the overall set of C18-thermally pretreated SPP silica stationary phases were determined using the Tanaka test. Complementary, the simplified Veuthey test was used to deeply study the silanol activity, considering a set of 7 basic solutes with various physicochemical properties. Both tests were also performed on different commercial SPP silica columns and different types of bonding chemistry (C18, Phenyl-hexyl, RP-amide, C30, aQ). Multivariate data analyses (hierarchical cluster analysis and principal component analysis) were carried out to define groups of stationary phases with similar chromatographic properties and situate them in relation to those commercially available. These different C18-thermally pretreated SPP silicas represented a wide range of stationary phases as they were spread out along the score plot. Moreover, this study highlighted that the thermal pretreatment improved the chemical stability of the SPP silica compare to untreated SPP silica and untreated porous silica. Consequently, higher thermal pretreatment can be applied (up to 900°C) before functionalization without destruction of the silica matrix. Indeed, a significantly lower dissolution of the thermally pretreated SPP silica under aggressive conditions could allow the use of the corresponding functionalized stationary phases at high temperature (60°C) with good lifetime of the columns.
authors.affiliation: Normandie Univ, EA3233, Sciences et Méthodes Séparatives, FR3038, IRCOF, 1 rue Tesniere, 76821 Mont Saint-Aignan Cedex, France.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Mignot
authors.affiliation: Normandie Univ, UMR 6014, Chimie Organique, Bioorganique: Réactivité et Analyse, FR3038, IRCOF, 1 rue Tesniere, 76821 Mont Saint-Aignan Cedex, France.
authors.forename: Muriel
authors.initials: M
authors.lastname: Sebban
authors.affiliation: Lip(Sys)(2) - LETIAM (FKA EA4041 Groupe de Chimie Analytique de Paris-Sud), Univ Paris-Sud, Université Paris-Saclay, IUT d'Orsay, Plateau de Moulon, F-91400 Orsay, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Tchapla
authors.affiliation: Interchim R&D, 211 bis avenue JF Kennedy, BP 1140, 03100 Montluçon, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Mercier
authors.affiliation: Normandie Univ, EA3233, Sciences et Méthodes Séparatives, FR3038, IRCOF, 1 rue Tesniere, 76821 Mont Saint-Aignan Cedex, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Cardinael
authors.affiliation: Normandie Univ, EA3233, Sciences et Méthodes Séparatives, FR3038, IRCOF, 1 rue Tesniere, 76821 Mont Saint-Aignan Cedex, France. Electronic address: valerie.agasse@univ-rouen.fr.
authors.forename: Valérie
authors.initials: V
authors.lastname: Peulon-Agasse
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation* / Q000379:methods; D016000:Cluster Analysis; D006358:Hot Temperature; D057927:Hydrophobic and Hydrophilic Interactions; D009682:Magnetic Resonance Spectroscopy; D016062:Porosity; D025341:Principal Component Analysis; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D012821:Silanes; C082343:silanol; D012822:Silicon Dioxide
keywords: High-performance-liquid-chromatography; Microwave irradiation; Octadecylsilane stationary phases; Principal component analysis; Silica thermal treatment; Superficially porous silica particles