Reversed-phase ion-pair chromatography of straight- and branched-chain dicarboxylic acids in urine as their 2-nitrophenylhydrazides

Hydrophilic sulfur sols prepared by reaction of aqueous sulfide and sulfite at low pH have been studied by chemical analysis, ion-pair chromatography, and reversed-phase HPLC. The approximate composition of the sol is x(NaHSO4/Na2SO4) ·ySn · zNa2SmO6 with n = 6-10 and m = 4-16. The elemental sulfur Sn accounts for 17% and the polythionate sulfur for 10% of the dry weight (sulfate: 18%). On aging of the sol at 20°C the long-chain polythionates decompose to elemental sulfur and tetrathionate as well as pentathionate. The higher chemical reactivity of this sol compared to S8 is explained by the fact that 45% of the zero oxidation state sulfur (S°) are present as non-S8 molecules.

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Reversed-phase ion-pair chromatography of hydroxyl functionalized imidazolium ionic liquid cations and its application in analysis of environmental water and measurement of hydrophobicity constants

Microchemical Journal ◽

10.1016/j.microc.2018.11.058 ◽

2019 ◽

Vol 145 ◽

pp. 988-995 ◽

Cited By ~ 10

Author(s):

Xinxin Jin ◽

Hong Yu ◽

Yajie Ma

Keyword(s):

Ionic Liquid ◽

Environmental Water ◽

Reversed Phase ◽

Ion Pair ◽

Imidazolium Ionic Liquid ◽

Ion Pair Chromatography

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Reversed-phase ion-pair chromatography with UV-absorbing ions in the mobile phase

Journal of Chromatography A ◽

10.1016/s0021-9673(00)82043-9 ◽

1981 ◽

Vol 218 ◽

pp. 31-43 ◽

Cited By ~ 168

Author(s):

M. Denkert ◽

L. Hackzell ◽

G. Schill ◽

E. Sjögren

Keyword(s):

Mobile Phase ◽

Reversed Phase ◽

Ion Pair ◽

Ion Pair Chromatography

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Studies in reversed-phase ion-pair chromatography I. Adsorption isotherms of tetraalkylammonium ion-pair reagents on lichrosorb rp-18 in methanol-water eluents

Journal of Chromatography A ◽

10.1016/0021-9673(83)80041-7 ◽

1983 ◽

Vol 260 ◽

pp. 337-345 ◽

Cited By ~ 55

Author(s):

A. Bartha ◽

Gy. Vigh

Keyword(s):

Adsorption Isotherms ◽

Reversed Phase ◽

Ion Pair ◽

Ion Pair Chromatography ◽

Tetraalkylammonium Ion

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Urinary free catecholamines determined by liquid chromatography--fluorometry.

Clinical Chemistry ◽

10.1093/clinchem/27.12.2060 ◽

1981 ◽

Vol 27 (12) ◽

pp. 2060-2063 ◽

Cited By ~ 20

Author(s):

G M Anderson ◽

J G Young ◽

P I Jatlow ◽

D J Cohen

Keyword(s):

Liquid Chromatography ◽

Ion Exchange ◽

Internal Standard ◽

Reversed Phase ◽

Ion Pair ◽

Native Fluorescence ◽

Exchange Column ◽

Ion Pair Chromatography ◽

Ion Exchange Column

Abstract Free norepinephrine, epinephrine, and dopamine are determined in urine after purification on a small ion-exchange column and concentration on alumina. The catecholamines are separated by reversed-phase ion-pair chromatography and are quantitated by measuring their native fluorescence (lambda ex 285 nm, lambda em 305 nm). The internal standard is dihydroxybenzylamine. Within-day CVs for the compounds ranged from 1.6 to 5.6%; between-day CVs were 6.6 to 9.8%.

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