Determination of aluminum in the human serum of a dialysis patient by ion-pair reversed-phase partition high-performance liquid chromatography

Abstract

An ion-pair reversed-phase partition high-performance liquid chromatography-spectrophotometric method is described for the determination of aluminum in human serum, based on its complexation with 2,2'-dihydroxyazobenzene. The chelate is separated on C18-bonded silica packing by using an aqueous methanol mobile phase containing tetrabutylammonium bromide and is detected with 0.005 AU full-scale at 510 nm. The proposed system offers a simple, sensitive, and selective method. The detection limits defined as twice the standard deviation of the blank signal, are 0.2 micrograms L-1 in pure solution and 6 micrograms L-1 in serum. The sample solution is prepared from 0.4 mL of serum after protein precipitation with hydrochloric acid and methanol. There was good agreement between the values obtained by this method and graphite furnace atomic absorption spectrophotometry. The aluminum concentrations in 121 patients on hemodialysis were 6-201 micrograms L-1.

Morin applied in speciation of aluminium in natural waters and biological samples by reversed-phase high-performance liquid chromatography with fluorescence detection

“…From the other point of view, since the toxic Al species are "labile monomeric", especially "the most toxic" forms, there is a need for a selective strategy for the species group rather than for each species [18]. A number of reports have published on reversed-phase high-performance liquid chromatographic (RP-HPLC) separation and determination of Al after pre-column complexation with 8-HQ [19], 2,2′-dihydroxyazobenzene [20], lumogallion [21], and the like. However, most of these reagents are excessively aggressive i.e.…”

Visual fluorimetry of trace aluminium by specific immobilization with o,o′-dihydroxyazobenzene on an octadecylsilanized silica thin layer

“…22 Kirby et al 21 reported that dhab forms 1+1 and 1+2 chelates with aluminium, gallium and indium in waterethanol mixtures. In our previous study, dhab was investigated for the determination of trace metal ions with HPLC [5][6][7][8][9] and visual methods. [10][11][12][13] However, the reaction of dhab with aluminium ion was not well characterized.…”

“…Precautions to reduce the aluminium contamination were discussed in our previous reports on HPLC. 7,8 In conventional TLC, the spotted sample solution spreads through the capillary of the substrates, such as filter paper or a thin layer. Therefore, these methods suffer from a lack of sensitivity.…”

“…As part of our studies on HPLC, it was previously reported that such a kinetic differentiation may serve as an effective technique for separating metal chelates. [5][6][7] Magnesium(II) and calcium(II) ions, which form fluorescent dhab chelates in the alkaline region, 21 do not interfere with the determination of aluminium under the pH conditions employed (pH 6.8). Thus none of these common metal ions has any significant effect on the samples studied in this work.…”

“…Furthermore, application of the specific immobilization has been extended to the determination of aluminium in water and tea samples. The reagent, dhab, has been used previously for the determination of trace metal ions through ion-pair reversed-phase partition HPLC, [5][6][7][8][9] ionpair adsorption film colorimetry 10,11 and micro ring fluorimetry. 12,13 We showed that visual methods have various advantages compared with instrumental ones.…”