Influence of alkyl chain length on the stability of n-alkyl-modified reversed phases. 1. Chromatographic and physical analysis

Abstract

Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Link to publication• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Several factor$ affecting long-term stability of modern reversed-phase htgh-performance llquld chromatography (RP-HPLC) phases are consldered and their lndlvldual contrlbutlons are evaluated In this paper and the following paper In this Issue. Tho stationary phases under study were Identically modifled on the same batch of slllca substrate to ellmlnate dmerences In substrate properties and synthesis conditions. Modtflcatlons with llgand alkyl chain length between C1 and C18 were performed such that an approxknately equal llgand density was obtained for the seven RP-HPLC phases studled. These n-alkyldimethyldloxydlane bonded phases were exposed to sknulated aglng experlments. A subsequent chromatographk characterlzatlon regarding changes In capacity, llp6phlUc and polar sdectlvlty, and slllca degradatlon related separation performance was carried out.

Comparison of the Chromatographic Retention in Octadecyl-Bonded Silica/(Methanol-Water) System with Partition Coefficient in Dodecane/(Methanol-Water) System

“…The free energy for the partition in the dodecane/ (methanol-water) system is represented by, -R T In P = A G s,dod -0 Gs,mw (2) where R the molar gas constant, T the temperature, and P is the partition coefficient of the solute. And the subscripts dod and mw indicate the dodecane phase and the methanol-water phase, respectively.…”

Temperature and pH‐stability of commercial stationary phases

“…It is interesting to note that the RX-C 8 column shows a very high resistance to hydrolysis although it consists of octyl-modified silica. As Hetem et al [38] have shown, the ligand alkyl chain length has a major influence on the stability of the column. The longer the alkyl ligands, the better the protection against the dissolution of the underlying silica matrix.…”

Evaluation of a monolithic epoxy silica support for penicillin G acylase immobilization

“…1). According to literature [15][16][17], the chemical shift values found for the 5,6-epoxypropoxy-3-propyl-1-silyl-silica (the abbreviation used in chromatography is epoxy) and 5,6-dihydroxypropoxy-3-propyl-1-silyl-silica (the abbreviation used in chromatography is diol) modified silica gels are summered in Table 2 Table 2 Chemical shift values found in literature [15][16][17] for the 5,6-epoxypropoxy-3-propyl-1-silyl-silica and 5,6-dihydroxypropoxy-3-propyl-1-silylsilica modified silica gels …”