Efeito do contra ion e de sua concentrao na reteno de -bloqueadores.

Efeito do contra ion e de sua concentrao na reteno de -bloqueadores.

FLIEGER, J. The effect of chaotropic mobile phase additives on the separation of selected alkaloids in reversed-phase high-performance liquid chromatography. Journal of Chromatography A, v. 1113, n. 1, p. 37-44, 2006.

Chromatograms of a mixtures of alkaloids (Acaffenine, Blaudanozine, Ccolchicine, Dboldine, Estrychnine, Fcinchonine, Gquinine) with different organic anions in the mobile phase.Effect of anionic additive type on the retention of investigated alkaloids. (*) For emetine and berberine the strongest retention was observed when hexafluorophosphate salt was added to the mobile phase. Their retention factors were higher than 25.

The effect of different anionic additives on retention, peak symmetry and efficiency of narcotine.Jones, Alan, Rosario LoBrutto, and Yuri Kazakevich. "Effect of the counter-anion type and concentration on the liquid chromatography retention of -blockers."Journal of Chromatography A964.1 (2002): 179-187.

Dependence of the retention factors for labetolol, acebutolol, and nadolol versus the concentration of perchlorate counter-anion in the mobile phase. Chromatographic conditions: column: Zorbax Eclipse XDB-C18(1504.6 mm), mobile phase: aqueous adjusted with perchloric acid and/or sodium perchlorate (pH 3.0)acetonitrile (70:30), flow-rate: 1 ml/min, detection: UV at 225 nm.

Dependence of the retention factors for metoprolol, pindolol, and nadolol versus the concentration of perchlorate counter-anion in the mobile phase. Chromatographic conditions: column: Zorbax Eclipse XDB-C18(1504.6 mm), mobile phase: aqueous adjusted with perchloric acid and/or sodium perchlorate (pH 3.0)acetonitrile (70:30), flow-rate: 1 ml/min, detection: UV at 225 nm.

Plot of the acebutolol retention factors versus counter-anion concentration in the mobile phase for different counter-anions used. Chromatographic conditions: column: Zorbax Eclipse XDB-C18(1504.6 mm), mobile phase: aqueous (pH 3.0)acetonitrile (70:30), flow-rate: 1 ml/min, detection: UV at 225 nm.

Plot of the acebutolol retention factors versus counter-anion concentration in the mobile phase for different counter-anions used. Chromatographic conditions: column: Zorbax Eclipse XDB-C18(1504.6 mm), mobile phase: aqueous (pH 3.0)acetonitrile (70:30), flow-rate: 1 ml/min, detection: UV at 225 nm.

Chromatograms of a mixture of -blockers ando-chloroaniline analyzed at constant pH and increasing perchlorate concentration.. Chromatographic conditions: column: Zorbax Eclipse XDB-C18(1504.6 mm), mobile phase: aqueous (pH 3.0)acetonitrile (70:30), flow-rate: 1 ml/min, detection: UV at 225 nm.FLIEGER, J. Effect of mobile phase composition on the retention of selected alkaloids in reversed-phase liquid chromatography with chaotropic salts. Journal of chromatography A, v. 1175, n. 2, p. 207-216, 2007

Experimental retention factors obtained for investigated alkaloids vs. trifluoroacetate and hexafluorophosphate concentration in mobile phase: 30% ACN/10mM phosphate buffer (dashed lines) and 30% ACN/30mM phosphate buffer pH=2.7 (continuous lines).

Graphic comparison of the desolvation parameters obtained using hexafluorophosphate as the counter-anion for two eluent systems: 25% THF/30mM phosphate buffer (THF) and 30% ACN/30mM phosphate buffer (ACN).

Chromatograms of mixtures of alkaloids obtained by the use of different mobile phases: (A) 35% ACN/10mM phosphate buffer (pH 2.7)+30mM NaPF6, (B) 40% MeOH/10mM phosphate buffer (pH 2.7)+30mM NaPF6, (C) 25% THF/10mM phosphate buffer (pH 2.7)+30mM NaPF6.

PAN, Li et al. Influence of inorganic mobile phase additives on the retention, efficiency and peak symmetry of protonated basic compounds in reversed-phase liquid chromatography.Journal of Chromatography A, v. 1049, n. 1, p. 63-73, 2004.

Effect of analyte load on: (A)N(h/2)and (B) tailing factor. Chromatographic conditions: 0.1% (v/v) H3PO4:acetonitrile eluent; benzylamine (5% acetonitrile), toluene (50% acetonitrile), Labetalol and 4-nitrophenol (25% acetonitrile), flow rate: 1.0mL/min; temperature: 25C; analyte load: 0.550g.

Chromatographic overlays of Labetalol analyzed at different analyte concentrations using increasing mobile phase concentration of perchlorate anion. Chromatographic conditions: analyte load: 3.3, 6.5, 31.2g, (a) 75%:0.1% (v/v) H3PO4:25% acetonitrile; (b) 75%:0.05% (v/v) HClO4:25% acetonitrile; (c) 75%:0.3% (v/v) HClO4:25% acetonitrile; (d) 75%:0.4% (v/v) HClO4:25% acetonitrile; (e) 75%:0.5% (v/v) HClO4:25% acetonitrile.

Chromatographic overlays of Dorzolamide HCl analyzed at different analyte concentrations using increasing mobile phase concentration of perchlorate anion. Chromatographic conditions: Analyte load: 1.4, 5.2, 9.2, 48g, (a) 90%:0.1% (v/v) H3PO4:10% acetonitrile; (b) 90%:0.05% (v/v) HClO4:10% acetonitrile; (c) 90%:0.3% (v/v) HClO4:10% acetonitrile; (d) 90%:0.4% (v/v) HClO4:10% acetonitrile; (e) 90%:0.5% (v/v) HClO4:10% acetonitrile.

Effect of counteranion type and concentration on analyte retention, peak efficiency,N(h/2), and tailing factor. Chromatographic conditions: Mobile phase: 75% aqueous:25% acetonitrile. Effective counteranion concentration for each mobile phase indicated in figure legend, flow rate: 1.0mL/min; temperature: 25C; analyte load: 0.5g; wavelength: 225nm.FLIEGER, J. Application of perfluorinated acids as ion-pairing reagents for reversed-phase chromatography and retention-hydrophobicity relationships studies of selected -blockers.Journal of Chromatography A, v. 1217, n. 4, p. 540-549, 2010.

Effect of ion-pairing reagent concentration in methanol/water mobile phase (acetic acid, AA; trifluoroacetic acid, TFAA; pentafluoropropionic acid, PFPA; heptafluorobutyric acid, HFBA) on retention coefficient of investigated -blockers.

Chromatograms of mixtures of -blockers obtained by the use of different mobile phases. The peaks order: atenolol, pindolol, nadolol, metoprolol, acebutolol.

SIR mass chromatograms of a mixture of oligolysine (dp=28) at different percentages of ACN in the mobile phase when heptafluorobutyric acid [HFBA] is 9.2mM. Column Waters XBridge Shield RP18 column (50mm4.6mm i.d.; pore size 135, particle size 3.5m) thermostated at 35C. The number on the top of each peak represents dp. Peaks corresponding to dp=7 and 8 are shown as an inset for 23% ACN.XIE, Wenchun; TERAOKA, Iwao; GROSS, Richard A. Reversed phase ion-pairing chromatography of an oligolysine mixture in different mobile phases: effort of searching critical chromatography conditions.Journal of Chromatography A, v. 1304, p. 127-132, 2013.

Effect of the HFBA concentration on the retention of oligolyisne. The number of lysine residues is indicated adjacent to each curve. (a) Results for all concentrations of HFBA. (b) Results at low concentrations. Theyaxis is in a log scale in (a) and in a linear scale in (b).XIE, Wenchun et al. Cooperative effect in ion pairing of oligolysine with heptafluorobutyric acid in reversed-phase chromatography.Journal of Chromatography A, v. 1218, n. 43, p. 7765-7770, 2011.LONG, Zhen et al. Strong cation exchange column allow for symmetrical peak shape and increased sample loading in the separation of basic compounds.Journal of Chromatography A, v. 1256, p. 67-71, 2012.Chromatograms of basic compounds separated on the Sunfire C18 column (A), XBridge C18 column (B) and the XCharge SCX column (C); Loading amounts on columns were 0.09035mg, 0.9035mg, and 3.614mg from (a) to (c). Peaks: 1=propranolol, 2=berberine, 3=amitriptyline.The mobile phases used for the separation of basic compounds on XCharge SCX column were A: acetonitrile, B: 100mmol/L NaH2PO4(pH=2.83) and C: water. The flow rate was 1.0mL/min and peaks were recorded at 260nm. Mobile phase composition on the XCharge SCX column was 50% A, 30% B. The optimized mobile phases on Sunfire C18 column were A: 0.1% FA in ACN (v/v) and B: 0.1% FA in water (v/v). Mobile phase composition on Sunfire C18 column started at 10% A and shifted to 35% A over 30min. Mobile phases for the analysis of basic compounds on XBridge C18 column were A: acetonitrile, B: 100mmol/L NH4HCO3(pH adjusted to 10.12 with ammonia solution) and C: water. Mobile phase composition on XBridge C18 column started at 20% A, 10% B, shifted to 30% A, 10% B from 0 to 10min, and finally shifted to 60% A, 10% B from 10 to 40min.