Strong cation exchange column

Figure 8.24 Separation of the major deoxyribonucleosides and their 5 - monophosphate deoxynucleotides on a strong cation exchange column (column one) and a reversed-phase column. The unseparated nucleosides. A, on the ion- exchange column were switched to the reversed-ptose column. Pe2dc Identification A = nucleosides, B d-CMP, C d-AMP, D - d-GJIP, E - d-CVD, P d-UKO, G THD, and H = d-AOO. (Reproduced with permission from ref. 298. Copyright Preston Publications, Inc.)...

Figure 5 Separation of pharmaceuticals, including amines, on strong cation exchange. Column 0.46 x 15 cm Merckosorb SI-60-SCX, 5 p. Eluent 50 mM aqueous ammonium formate-10% ethanol, pH 4.8. Flow 1 ml/min. Temperature 50°C. The peaks are (1) aspirin, (2) paracetamol, (3) phenacetin, (4) caffeine, (5) phenylephrine, (6) salbutamol. (Reproduced with permission of Elsevier Science from Cox, G. B., Loscombe, C. R., Slucutt, M. J., Sugden, K., and Upheld, J. A., /. Chromatogr., 117, 269, 1976).

The polyamines putrescine, cadaverine, spermidine, and spermine, which are seen at elevated levels in some victims of cancer, were separated on a Technicon (The Technicon Company Chauncey, NY) TSM Amino Acid Analyzer packed with an 8% divinylbenzene-co-polystyrene sulfonated resin with post-column ninhydrin detection.111 Amines such as ethanolamine, noradrenaline, hexamethylene diamine, methoxytryptamine, spermine, and spermidine were separated from amino acids on a DC-4A cation exchange resin.112 A similar approach, using a Beckman Model 121M amino acid analyzer equipped with an AA-20 column, was also successful.113 A Polyamin-pak strong cation exchange column (JASCO) was eluted with a citrate buffer for the detection of putrescene, spermine, cadaverine, and 1,5-diaminohex-ane from rat thymus.114 A post-column o-phthaldehyde detection system was used. 

Ion-exchange chromatography techniques that provide cationic surfactant residues suitable for a conductivity analysis are also developed [47,48]. They usually employ strong cation exchange columns and a mobile-phase based on an organic solvent (acetonitrile or... 

Fig. 1.43 Strategies for protein identification. (A) 2D gel electrophoresis approach. (B) 2D liquid chromatography approach. lEF Isoelectric focusing, sex strong cation exchange column, RP reverse phase column, SDS-PAGE sodium dodecyl sulfate polyacrylamide gel electrophoresis.

Fig. 1.45 Example of a 2D nano LC-MS/MS analysis of a C elegans extract. (A) Fraction 2, 4 mM KCI salt elution on the strong cation exchange column. (B) Full scan MS spectrum of the peak eluting at RT 26.3 min in (A). (C) product ion spectrum of the doubly charged precursor of (B) at m/z 784.8. Y fragments are typical for C-terminal fragments while b ions are typical for N-terminal fragments.

Analysis of adrenaline (adr), noradrenaline (nadr) and dopamine (DA) in urine using (A) An ODS column with ionpairing agent in citrate buffer pH 5.0 with 2% tetrahydrofuran (THF) as the mobile phase (B) a strong cation exchange column with citrate buffer pH 5.0 with 7% THF as the mobile phase. The eluent was monitored by electrochemical detection at a potential of 0.7 V. Methyidopamine (MDA) was used as an internal standard and added to the urine before extraction. Reproduced with permission from J. Chromatogr. Biomed. Apps. (see Reference 10). 

Persson and Irgum have described a method for the determination of DMM A in sea water in the sub-ppm range by electrothermal atomic absorption spectrometry after preconcentration on a strong cation exchange column and elution with ammonia. 

Since 2002, on-line nanoscale LC-ESI-MS/MS was used for the analysis of the peptidome of. Drosophila samples. This combination greatly improves the sensitivity of detection. Starting from only 50 larval Drosophila CNS, 28 peptides were isolated and sequenced in an on-line quadrupole time-of-flight mass spectrometer [27]. Later, two-dimensional capillary LC-ESI-MS/MS has enhanced the coverage of this peptidomics analysis with the identification of twenty additional peptides [31]. The CNS extract has been first fractionated onto a strong cation-exchange column then onto a reversed-phase column before ESI-MS/MS analysis. Recently this approach has been applied to Drosophila larvae hemolymph to identify new peptides induced by a septic injury [22]. Most of the identified molecules correspond to truncated forms or propeptides of known AMPs and DIMs [15,20,21], but two previously unknown peptide precursors, potentially involved in the innate immune response, have been also detected by this way. 

Figure 12 Separation of a mixture of protein standards on two strong cation-exchange columns. ICkromatographic conditions Sample (1) myoglobin (2) libcmuc-lease A (3) chymotrypsinogen A (4) cytochrome c (S) lysozyme. Columns top— Protein-Pak SP 8 HR Minicolumn, S mm x SO mm. Waters Corp4 bottom—Mono S, S mm X SO mm, Pharmacia. Buffer A—20 mM sodium phosphate pH 7 bulfer B—buffer A -i-1 M sodium chloride. Gradient 0-S0% buffer B in 40 min at 0i4 mL/min. Detection 280 nm.] (Chromatograms courtesy of Waters Cotp.)...

Figure 7 Monitoring effect of pH on a strong cation-exchange column with synthetic peptide standards. Column SynChropak S300 (250 x 4,1 mm ID, 6.5 (im particle size, 300 A pore size SynChrom (Lafayette, IN). Mobile phase linear AB gradient, where buffer A is 5mM aqueous KHaP04 [pH 6.5 (top) or pH 3.0 (bottom)] and buffer B is buffer A plus 1 M NaCI gradient rate, 20 mM NaCI/min following 5-min isocratic elution with buffer A flow rate, 1 mL/min temperature, 26 C. Peptide standards Cl, C2, C3, and C4 (see Table 1 for sequences) contain net charges of -f 1, -i-2, -i-3, and -i-4, respectively. (From Ref. 38.)...

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