Ion par chromatography

Efeito do contra ion e de sua concentração na retenção de β-

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(A—caffenine, B—laudanozine, C—colchicine, D—boldine, E—strychnine, F—cinchonine, G—quinine) with different organicanions in the mobilephase.

Effect of anionic additive type on the retention of investigated alkaloids. (*) For emetine andberberine the strongest retention was observed when hexafluorophosphate salt was added tothe 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 andconcentration on the liquid chromatography retention of β-blockers." Journal ofChromatography A 964.1 (2002): 179-187.

Dependence of the retention factors for labetolol, acebutolol, and nadolol versus theconcentration of perchlorate counter-anion in the mobile phase. Chromatographicconditions: column: Zorbax Eclipse XDB-C18 (150×4.6 mm), mobile phase: aqueousadjusted 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 theconcentration of perchlorate counter-anion in the mobile phase. Chromatographicconditions: column: Zorbax Eclipse XDB-C18 (150×4.6 mm), mobile phase: aqueousadjusted 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 phasefor different counter-anions used. Chromatographic conditions: column: Zorbax Eclipse XDB-C18 (150×4.6 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 phasefor different counter-anions used. Chromatographic conditions: column: Zorbax Eclipse XDB-C18 (150×4.6 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 β-blockers and o-chloroaniline analyzed at constant pH and increasing perchlorate concentration.. Chromatographic conditions: column: Zorbax Eclipse XDB-C18 (150×4.6 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 chaotropicsalts. Journal of chromatography A, v. 1175, n. 2, p. 207-216, 2007

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

Graphic comparison of thedesolvation parametersobtained usinghexafluorophosphate asthe counter-anion for twoeluent systems: 25%THF/30 mM phosphatebuffer (THF) and 30%ACN/30 mM phosphatebuffer (ACN).

Chromatograms of mixtures of alkaloids obtained by the use of different mobile phases: (A) 35% ACN/10 mM phosphate buffer (pH 2.7) + 30 mM NaPF6, (B) 40% MeOH/10 mM phosphatebuffer (pH 2.7) + 30 mM NaPF6, (C) 25% THF/10 mM phosphate buffer (pH 2.7) + 30 mM 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 analyteload on: (A) N(h/2) and (B) tailing factor. Chromatographicconditions: 0.1% (v/v) H3PO4:acetonitrileeluent; benzylamine (5% acetonitrile), toluene (50% acetonitrile), Labetalol and 4-nitrophenol (25% acetonitrile), flowrate: 1.0 mL/min; temperature: 25 °C; analyte load: 0.5–50 μg.

Chromatographic overlays of Labetalol analyzed at different analyte concentrations usingincreasing mobile phase concentration of perchlorate anion. Chromatographic conditions:analyte load: 3.3, 6.5, 31.2 μg, (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 usingincreasing mobile phase concentration of perchlorate anion. Chromatographic conditions:Analyte load: 1.4, 5.2, 9.2, 48 μg, (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), andtailing factor. Chromatographic conditions: Mobile phase: 75% aqueous:25% acetonitrile.Effective counteranion concentration for each mobile phase indicated in figure legend, flow rate:1.0 mL/min; temperature: 25 °C; analyte load: 0.5 μg; wavelength: 225 nm.

FLIEGER, J. Application of perfluorinated acids as ion-pairing reagents for reversed-phase chromatography and retention-hydrophobicityrelationships studies of selected β-blockers. Journal of Chromatography A, v. 1217, n. 4, p. 540-549, 2010.

Effect of ion-pairing reagentconcentration inmethanol/water mobilephase (acetic acid, AA;trifluoroacetic acid, TFAA;pentafluoropropionic acid,PFPA; heptafluorobutyricacid, HFBA) on retentioncoefficient of investigatedβ-blockers.

Chromatograms of mixtures of β-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 = 2–8) at different percentages of ACN in the mobile phase when heptafluorobutyric acid [HFBA] is 9.2 mM. Column Waters XBridge Shield RP18 column (50 mm × 4.6 mm i.d.; pore size 135 Å, particle size 3.5 μm) thermostated at 35 °C. 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. The y axis is in a log scale in (a) and in a linear scale in (b).

XIE, Wenchun et al. Cooperative effect in ionpairing of oligolysine with heptafluorobutyricacid in reversed-phasechromatography. Journal of ChromatographyA, v. 1218, n. 43, p. 7765-7770, 2011.

LONG, Zhen et al. Strong cationexchange 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), XBridgeC18 column (B) and the XChargeSCX column (C); Loading amounts on columns were 0.09035 mg, 0.9035 mg, and 3.614 mg 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: 100 mmol/L NaH2PO4 (pH = 2.83) and C: water. The flow rate was 1.0 mL/min and peaks were recorded at 260 nm. 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 30 min. Mobile phases for the analysis of basic compounds on XBridge C18 column were A: acetonitrile, B: 100 mmol/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 10 min, and finally shifted to 60% A, 10% B from 10 to 40 min.