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LC-CAP

The principle of the liquid chromatography under critical conditions (LC CC) was elucidated in Section 16.3.3. The mutual compensation of the exclusion—entropy and the interaction—enthalpy-based retention of macromolecules can be attained when applying in the controlled way the interactions that lead to either adsorption or enthalpic partition. The resulting methods are called LC at the critical adsorption point (LC CAP) or LC at the critical partition point (LC CPP), respectively. The term LC at the point of exclusion-adsorption transition (LC PEAT) was also proposed for the procedures employing compensation of exclusion and adsorption [161]. It is anticipated that also other kinds of enthalpic interactions, for example the ion interactions between column packing and macromolecules can be utilized for the exclusion-interaction compensation. [Pg.478]

Scheme 4.4 Chemical structure of glassy chiral LC capping agent 12... Scheme 4.4 Chemical structure of glassy chiral LC capping agent 12...
Fig. 2. Schematic representation of LC-CAP, LC-LCA, and LC-LCD. Reprinted from [50] with permission... Fig. 2. Schematic representation of LC-CAP, LC-LCA, and LC-LCD. Reprinted from [50] with permission...
Many chromatographic method combinations are possible and have indeed been used e.g. SEC, LAC, LC-CAP, GC, SEC, CE, TREE [2]. Obviously, techniques such as GC and SEC, which destroy the mobile phase, can only be used as the final dimension. Most popular to date have been HPLCxGPC combinations, because comprehensive 2D chromatography was first established in synthetic polymer work. Details on the methodology and experimental implementation can be foimd in the literature [3]. [Pg.530]

Data are presented manifesting the role of column packings from the point of view of both their pore size and surface chemistry. Bare silica gels that are the most commonly used LC CAP column packings and model macromolecules, viz. narrow PMMA, were investigated. 20 refs. [Pg.115]

Several mixtures of hexanethiol capped gold nanopartides and triphenylene based discotic LCs have been studied. These mixtures display liquid crystal behavior (columnar mesophases) and an enhancement in the DC conductivity, due to the inclusion of gold nanoparticies into the matrix of the organic LC [70]. Other studies of mixtures of gold nanoparticies with mesogens indude a series of cholesteryl phenoxy alkanoates. The inclusion of the nanopartides does not change the inherent liquid crystal properties of the cholesteryl derivative but the mesophases are thermally stabilized [71]. [Pg.389]

Water samples, received from the respective groundwater trials, are analyzed by direct aqueous injection (DAI) by LC/ESI-MS/MS. A 1-mL volume of the water is pipetted into a 1.8-mL autosampler vial. The internal standard solution is added (200 qL) and mixed. The vials are capped and analyzed by LC/ESI-MS/MS using the selected reaction monitoring (SRM) mode. [Pg.1321]

Prepare a calibration curve in the following manner. Measure 1 mL of control water into a series of 1.8-mL autosampler vials. Fortify each water sample with 200 o.L of the appropriate calibration standard to make a 0.1, 0.5 and 2.5ngmL calibration curve. Mix the sample by vortexing or shaking the vial and analyze 200 iL by LC/ESI-MS/MS. For well and lysimeter water, mix 1 mL of sample water with 200 uL of the lOngmL" mixed internal standard solution in a 1.8-mL autosampler vial, cap the vial, mix the contents and analyze 200 iL by LC/ESIMS/MS. [Pg.1323]

Figures 10 and 11 show the structure of the hindered phenolic antioxidant Irganox 1010 (Ciba) and its negative ion APCI mass spectra, respectively. Separation was achieved under the following LC conditions Column Aqua Cl 8 (Phenomenex) 3 pm, 150x2.00 mm, 15% carbon loading, proprietary end capping. Column Temp 50°C. Injection volume 5 pi. Figures 10 and 11 show the structure of the hindered phenolic antioxidant Irganox 1010 (Ciba) and its negative ion APCI mass spectra, respectively. Separation was achieved under the following LC conditions Column Aqua Cl 8 (Phenomenex) 3 pm, 150x2.00 mm, 15% carbon loading, proprietary end capping. Column Temp 50°C. Injection volume 5 pi.
The FTIR spectra (KBr discs) were recorded in the 4,000 00 cm range on a Mattson 1000 FTIR spectrometer. The spectra and absorbance measurements were recorded on a Agilent 8453 UV-visible Spectroscopy System. Proton NMR spectra were recorded on a Bracker AC-400 MHz (CDCy spectrometer. The elemental analyses and mass spectra (LC-MS) were determined in the TUBITAK Laboratory (Center of Science and Technology Research of Turkey). Melting points were obtained with a Gallenkamp CAP MPD-350 apparatus in open capillaries. [Pg.376]

Chloramphenicol, FLO, and TAP have strong UV absorption, and they could be determined directly by HPLC (9). Unlike many of the more polar antibiotics, these three compounds could be extracted with an organic solvent. A single shake-out with ethyl acetate was sufficient for the quantitative extraction of CAP and FLO from milk (5). The extract was cleaned up using C18 and Florisil SPE cartridges. A review of methods for the determination of three amphenicol residues in food, including eight GC methods and six LC methods for CAP in milk, has also been reported (9). [Pg.653]


See other pages where LC-CAP is mentioned: [Pg.274]    [Pg.480]    [Pg.370]    [Pg.357]    [Pg.113]    [Pg.305]    [Pg.145]    [Pg.3]    [Pg.9]    [Pg.10]    [Pg.10]    [Pg.38]    [Pg.38]    [Pg.274]    [Pg.480]    [Pg.370]    [Pg.357]    [Pg.113]    [Pg.305]    [Pg.145]    [Pg.3]    [Pg.9]    [Pg.10]    [Pg.10]    [Pg.38]    [Pg.38]    [Pg.415]    [Pg.172]    [Pg.335]    [Pg.594]    [Pg.1183]    [Pg.1184]    [Pg.5]    [Pg.173]    [Pg.193]    [Pg.288]    [Pg.54]    [Pg.467]    [Pg.530]    [Pg.81]    [Pg.82]    [Pg.368]    [Pg.265]    [Pg.99]    [Pg.5]    [Pg.727]    [Pg.654]    [Pg.655]   
See also in sourсe #XX -- [ Pg.9 , Pg.10 ]




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Analysis of CAP in Herbs and Grass (Feed) Using LC-MS

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