Properties of chemically bonded phases

Engelhardt, H.; Ahr, G.

doi:10.1007/bf02260156

Cited by 122 publications

(35 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The synthesis and/or size classification of silica particles is easily done to provide monodisperse particles of the desired pore size [22][23][24]. In addition, a large variety of silanes are available to modify silica's surface through silanization and make different bonded phases [25,26]. The high mechanic strength and the high efficiency ensured by the fast mass transfer characteristics of bonded phases are also major advantages of silica-based stationary phases over polymer-based stationary phases [27][28][29].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of silica-based hyper-crosslinked sulfonate-modified reversed stationary phases

Luo

Carr

2008

Journal of Chromatography A

View full text Add to dashboard Cite

A novel type of silica-based sulfonate-modified reversed phase ( − SO 3 -HC-C 8 ) has been synthesized; it is based on a newly developed acid stable "hyper-crosslinked" C 8 derivatized reversed phase, denoted HC-C 8 . The − SO 3 -HC-C 8 phases containing controlled amounts of sulfonyl groups were made by sulfonating the aromatic hyper-crosslinked network of the HC-C 8 phase at different temperatures. The − SO 3 -HC-C 8 phases are only slightly less hydrophobic than the parent HC-C 8 phase. The added sulfonyl groups provide a unique strong cation-exchange selectivity to the hydrophobic hyper-crosslinked substrate as indicated by the very large C coefficient as shown by Snyder's hydrophobic subtraction reversed-phase characterization method. This cation-exchange activity clearly distinguishes the sulfonated phase from all other reversed phases as confirmed by the extraordinary high values of Snyder's column comparison function F s . In addition, as was found in previous studies of silica-based and zirconia-based reversed phases, a strong correlation between the cation-exchange interaction and hydrophobic interaction was observed for these sulfonated phases in studies of the retention of cationic solutes. The overall chromatographic selectivity of these − SO 3 -HC-C 8 phases is greatly enhanced by its high hydrophobicity through a "hydrophobically assisted" ion-exchange retention process.

show abstract

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of silica-based hyper-crosslinked sulfonate-modified reversed stationary phases

Luo

Carr

2008

Journal of Chromatography A

View full text Add to dashboard Cite

show abstract

“…Basing on these data it can be stated, that the values of such parameters as specific surface area (SBET) , pore diameter (D) and pore volume (Vp) are within the range of values corresponding to that of a theoretically optimal adsorbent [16,[19][20][21]. This conclusion concerns also the pH of a 5 % aqueous suspension of the gel defined in the literature as a measure of purity of the surface [22][23][24]. The actual pH value differs only slightly (by 2 %) from the theoretical value (pH = 5.6).…”

Section: Characteristics Of the Surface Of The Packing Materialsmentioning

confidence: 98%

“…Referring to the relevant literature [16,19,21,[23][24][25] one can presume that the silica used was relatively pure.…”

Section: Characteristics Of the Surface Of The Packing Materialsmentioning

confidence: 99%

Polyfunctional chemically bonded stationary phase for reversed phase high-performance liquid chromatography

et al. 1998

View full text Add to dashboard Cite

“…Methylene selectivity depends on the hydrophobic interaction between the stationary phase and the compounds investigated. It has been reported that methylene selectivity increases with chain length of ligand [91,92,93], with bonded phase carbon loading [94,95], as well as with bonded phase coverage [96,97]. Hydrophobic or methylene selectivity of a column is generally defined as the relative retention of ethylbenzene (EB) and toluene (T).…”

Section: Hydrophobic or Methylene Selectivitymentioning

confidence: 99%

Evaluation of column characteristics in RPLC using linear solvation energy relationships (LSERs)

Szepesy¹

2003

J of Separation Science

View full text Add to dashboard Cite

Evaluation of column characteristics in RPLC using linear solvation energy relationships (LSERs)An overview is given of our studies on the use of linear solvation energy relationships (LSERs) for evaluation and comparison of RP-HPLC columns. From among the columns investigated, 19 columns of different types, viz. 12 narrow-pore, 7 wide-pore silicas containing various ligands (C18, C8, C4, CN) and obtained from 7 manufacturers, were compared and evaluated. Retention factors of 32 solutes of widely differing chemical properties were measured and evaluated to determine the effect of stationary phase properties on the retention of various types of solutes. When the same mobile phase is used with the different columns, the regression coefficients determined by multivariate regression characterize the various stationary phases. The columns investigated were evaluated on the basis of the relative importance of the various types of interactions reflecting the various surface properties of the stationary phases. Since the selectivity of separation is more important than is absolute selectivity, we have investigated and compared the various selectivity terms, hydrophobic, polar, and specific selectivity, displayed by the various columns, for the separation of different types of compounds. As the selectivity of separation depends also on the type and composition of the mobile phase, the effect of mobile phase on the various selectivity terms was evaluated.

show abstract

Properties of chemically bonded phases

Cited by 122 publications

References 49 publications

Synthesis and characterization of silica-based hyper-crosslinked sulfonate-modified reversed stationary phases

Synthesis and characterization of silica-based hyper-crosslinked sulfonate-modified reversed stationary phases

Polyfunctional chemically bonded stationary phase for reversed phase high-performance liquid chromatography

Evaluation of column characteristics in RPLC using linear solvation energy relationships (LSERs)

Contact Info

Product

Resources

About