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Reversed-phase chromatography sorbents

General Characteristics of Reversed-Phase Chromatography Sorbents... [Pg.578]

Surface Modification Considerations for the Selection of Reversed-Phase Chromatography Sorbents for Peptide Isolation... [Pg.583]

Recently, new approaches of sorbent construction for reversed-phase chromatography have been developed. Silicas modified with hydrocarbon chains have been investigated the most and broadly utilized for these aims. Silica-based materials possess sufficient stability only in the pH 2-8 range. Polymeric HPLC sorbents remove these limitations. Tweeten et al. [108] demonstrated the application of stroongly crosslinked styrene-divinylbenzene resins for reversed-phase chromatography of peptides. [Pg.167]

These sorbents may be used either for selective fixation of biological molecules, which must be isolated and purified, or for selective retention of contaminants. Selective fixation of biopolymers may be easily attained by regulation of eluent polarity on the basis of reversed-phase chromatography methods. Effective isolation of different nucleic acids (RNA, DNA-plasmid) was carried out [115, 116]. Adsorption of nucleosides, nucleotides, tRN A and DNA was investigated. It was shown that nucleosides and nucleotides were reversibly adsorbed on... [Pg.167]

Chapter 3 through Chapter 8 deal with the basic aspects of the practical uses of PLC. Chapter 3 describes sorbent materials and precoated layers for normal or straight phase (adsorption) chromatography (silica gel and aluminum oxide 60) and partition chromatography (silica gel, aluminum oxide 150, and cellulose), and precoated layers for reversed-phase chromatography (RP-18 or C-18). Properties of the bulk sorbents and precoated layers, a survey of commercial products, and examples of substance classes that can be separated are given. [Pg.8]

The TLC process is an off-line process. A number of samples are chromatographed simultaneously, side-by-side. HPTLC is fast (5 min), allows simultaneous separation and can be carried out with the same carrier materials as HPLC. Silica gel and chemically bonded silica gel sorbents are used predominantly in HPTLC other stationary phases are cellulose-based [393]. Separation mechanisms are either NPC (normal-phase chromatography), RPC (reversed-phase chromatography) or IEC (ion-exchange chromatography). RPC on hydrophobic layers is not as widely used in TLC as it is in column chromatography. The resolution capabilities of TLC using silica gel absorbent as compared to C S reversed-phase absorbent have been compared for 18 commercially available plasticisers, and 52 amine and 36 phenolic AOs [394]. [Pg.221]

K. Kalghatgi and C. Horvath, Micropellicular sorbents for rapid reversed-phase chromatography of proteins and peptides, in Analytical Biotechnology, Capillary Electrophoresis, and Chromatography, C. Horvath and J.G. Nikelly (Eds.), American Chemical Society, Washington, D.C., 1990, p. 162. [Pg.64]

Sorbent and Mobile-Phase Considerations for Reversed-Phase Chromatography and Hydrophobic Interaction Chromatography... [Pg.578]

YF Maa, Cs Horvath. Rapid analysis of proteins and peptides by reversed-phase chromatography with polymeric micro-pellicular sorbents. J Chromatogr 445 71-86, 1988. [Pg.160]

Micropellicular Sorbents for Rapid Reversed-Phase Chromatography of Proteins and Peptides... [Pg.162]

For reverse-phase chromatography purposes, silica sorbents are commonly modified by hydrophobic ligands by means of silanes. These systems are therefore particularly suitable for water intrusion experiments [7]. We studied the influence of the chain nature (perfluorated, alkyl), the chain length and the type of bonding chemistry (mono or trifunctional, chloro- or alkoxy- silanes) on the hydrophobic properties of silica gels. [Pg.198]

Due to the medium polarity of polyamide 6, the sorbent can be made more or less hydrophobic than the mobile phase selecting appropriate polar and nonpolar eluents therefore, normal- and reversed-phase chromatography and also two-dimensional technique can be developed. [Pg.1638]

Reversed-phase chromatography widespread use of charcoal as a sorbent 1960 Bonded sorbents synthesized 1968 Polymeric sorbents, XAD resins developed... [Pg.19]

Chapter 1). The widespread use of the C-18 for reversed-phase sorption is a result of the popular use of C-18 columns in high-pressure liquid chromatography (HPLC). For this reason, it gained immediate popularity for SPE applications. Other reversed phases include, C-8, C-4 (wide pore), C-2, C-1, cyclohexyl, and phenyl groups. The most commonly used reversed-phase polymeric sorbent in SPE is the styrene-divinylbenzene, or SDB. Graphitized carbon is also used. [Pg.76]

Figure 4.10. Plot of the retention factor as a function of the volume fraction (% v/v) of organic solvent in reversed-phase chromatography. Stationary phase is an octadecylsiloxane-bonded silica sorbent with methanol-water as the mobile phase. Solute identification 1 = naphthalene 2 = bromobenzene 3 = acetophenone 4 = 2-phenylethanol and 5 = benzamide. Figure 4.10. Plot of the retention factor as a function of the volume fraction (% v/v) of organic solvent in reversed-phase chromatography. Stationary phase is an octadecylsiloxane-bonded silica sorbent with methanol-water as the mobile phase. Solute identification 1 = naphthalene 2 = bromobenzene 3 = acetophenone 4 = 2-phenylethanol and 5 = benzamide.
Influence of solvent type on the system constants of the solvation parameter model for a cyanopropylsiloxane-bonded silica sorbent in reversed-phase chromatography (r = 0 in all cases)... [Pg.310]

Figure 6.13. Separation mode selection guide for TLC. LSC = liquid-solid chromatography on an inorganic oxide adsorbent BPC = liquid-solid chromatography on a chemically-bonded sorbent RPC = reversed-phase chromatography with a water-containing mobile phase and chemically-bonded stationary phase IPC = ion-pair chromatography with reversed-phase separation conditions and PC = precipitation chromatography. (From ref. [151] Elsevier)... Figure 6.13. Separation mode selection guide for TLC. LSC = liquid-solid chromatography on an inorganic oxide adsorbent BPC = liquid-solid chromatography on a chemically-bonded sorbent RPC = reversed-phase chromatography with a water-containing mobile phase and chemically-bonded stationary phase IPC = ion-pair chromatography with reversed-phase separation conditions and PC = precipitation chromatography. (From ref. [151] Elsevier)...
Hennion MC and Coquart V (1993) Comparison of reversed-phase extraction sorbents for the on-line trace enrichment of polar organic compounds in environmental aqueous samples. Journal of Chromatography 642 211-224. [Pg.1214]

Solid-phase extraction is also often used to remove interfering coextracted compounds. Solid-phase extraction columns contain either non-polar reversed-phase Cig sorbents or polar sorbents (such as alumina, aminopropyl acid, and propylsulfonic acid). Matrix solid-phase dispersion cleanup using reversed-phase Cig material has been also employed for the determination of oxohnic acid in catfish muscle.In-tube solid-phase microextraction (SPME) based on poly(methacrylic acid-ethylene glycol dimethacrylate) (MAA-EGDMA) monolith coupled to high-preformance liquid chromatography (HPLC) with ultraviolet (UV) and fluorescence detection (FED) was... [Pg.930]

See other pages where Reversed-phase chromatography sorbents is mentioned: [Pg.161]    [Pg.408]    [Pg.516]    [Pg.300]    [Pg.61]    [Pg.296]    [Pg.60]    [Pg.66]    [Pg.547]    [Pg.1216]    [Pg.309]    [Pg.162]    [Pg.1342]    [Pg.416]    [Pg.20]    [Pg.269]    [Pg.309]    [Pg.319]    [Pg.327]    [Pg.609]    [Pg.85]    [Pg.200]    [Pg.3431]    [Pg.935]    [Pg.99]    [Pg.383]   
See also in sourсe #XX -- [ Pg.110 , Pg.111 , Pg.112 , Pg.113 , Pg.156 , Pg.157 , Pg.158 , Pg.159 , Pg.160 , Pg.161 ]



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