Amberlite XAD-4 Resin Column Research Articles

Chromium Speciation Using an Aminated Amberlite XAD-4 Resin Column Combined with Microsample Injection-Flame Atomic Absorption Spectrometry

Amberlite XAD-4 resin (AXAD-4) was chemically modified to an aminated Amberlite XAD-4 (AAXAD-4) resin and characterized by infrared spectroscopy. AAXAD-4 resin was used as an efficient solid phase for the preconcentration and speciation of Cr(III) and Cr(VI) ions by column technique. The concentration of chromium species was determined by microsample injection system-flame atomic absorption spectrometer (MIS-FAAS). Selective retention of Cr(III) ions was achieved at pH 8.0 and eluted using 1.0 mL of 3.0 mol L-1 HCl and 1.0 mL of 2.0 mol L-1 NaOH, successively, at the flow rate of 5.0 mL min-1. The maximal sorption capacity of AAXAD-4 resin for Cr(III) ions was found to be 67.0 mg g-1. The limit of detection (LOD) and limit of quantitation (LOQ) for Cr(III) ions were found to be 0.041 and 0.131 ∆g L-1, respectively, with preconcentration factor (PF) of 375 and relative standard deviation (RSD) of 3.75% (n = 11). The method was validated using certified reference materials (CRMs) and successfully applied to the real samples, spiked with Cr(III) and Cr(VI) ions.

Flame Atomic Absorption Spectrometry Determination of Trace Amounts of Cadmium and Zinc in Water Samples after Preconcentration onto Modified Amberlite XAD‐4 Resin

AbstractIn the present article, a procedure for the simultaneous separation and preconcentration of trace amounts of cadmium and zinc is proposed. It is based on the adsorption of cadmium and zinc ions onto a column of Amberlite XAD‐4 resin loaded with aluminon reagent. Cadmium and zinc ions are quantitatively retained on the column in the pH range from 6.5–7.5, at a flow rate of 2 mL min–1. The cadmium and zinc ions are eluted with 5.0 mL of 5 mol L–1 HNO3 solution. Cadmium and zinc are measured by flame atomic absorption spectrometry (FAAS). In the present case, 0.1 μg of cadmium and 0.5 μg of zinc can be concentrated in the column from 1000 mL of aqueous sample, where their concentrations are as low as 0.1 and 0.5 ng mL–1, respectively. The relative standard deviations, for seven replicated determinations of 1.0 μg mL–1 of cadmium and zinc, are 1.2 and 1.1%, respectively. The detection limits for cadmium and zinc in the original solution are 0.02 and 0.11 ng mL–1, respectively. The interference of a large number of anions and cations has been studied and the optimized conditions are utilized for the determination of trace amounts of cadmium and zinc in different environmental and standard samples.

Determination of Trace Amounts of Lead and Manganese in Water Samples After Simultaneous Preconcentration onto Modified Amberlite XAD-4 Resin

A procedure for simultaneous separation and preconcentration of trace amounts of manganese and lead has been proposed. It is based on the adsorption of manganese and lead ions onto a column of Amberlite XAD-4 resin loaded with pyrocatechol reagent. Manganese and lead were quantitatively retained on the column in the pH range 4.0-6.5 at a flow rate of 2 mL/min. The manganese and lead ions were eluted with 5.0 mL of 4 M HNO3 solutions. Manganese and lead were measured by flame atomic absorption spectrometry. In this case, 100.0 ng manganese and 1000.0 ng lead were concentrated in the column from 800 mL of aqueous sample, where their concentrations were as low as 0.125 and 1.25 ng/mL, respectively. Seven replicate determinations of mixtures of 1.0 microg/mL manganese and 2.0 microg/mL lead in the final solution gave a mean absorbance of 0.1926 and 0.0832 with RSD values of +/- 1.1 and +/- 1.2%, respectively. The LODs were 1.76 ng/mL for Mn(ll) and 37.28 ng/mL for Pb(ll) (3 delta(bl)/m) in the final solution, with a preconcentration factor of 160. Sensitivities for 1% absorbance for Mn(ll) and Pb(ll) were 7.0 and 74.7 ng/mL, respectively. The interference of a large number of anions and cations has been studied and the optimized conditions were used for determination of trace amounts of manganese and lead in various environmental and standard samples.

Solid phase extraction of chromium(VI) from aqueous solutions by adsorption of its diphenylcarbazide complex on an Amberlite XAD-4 resin column

A method has been developed for the solid phase extraction of chromium(VI) based on the adsorption of its diphenylcarbazide complex on an Amberlite XAD-4 resin column. The influence of acidity, stability of the column, sample volume, flow rate and interfering ions were studied in detail. The adsorbed complex could be eluted using acetone–sulfuric acid mixture and the concentration of chromium was determined using visible spectrophotometry. A detection limit of 6 μg L −1 could be achieved. A preconcentration factor of 27 could be obtained for 400 mL sample volume. The validity of the method was checked in spiked water samples and electroplating wastewater.

The use of Bacillus subtilis immobilized on Amberlite XAD-4 as a new biosorbent in trace metal determination

The present work proposes the use of Bacillus subtilis immobilized on Amberlite XAD-4 as new biosorbent in trace metal determination. The procedure is based on the biosorption of Cu and Cd ions on a column of Amberlite XAD-4 resin loaded with dried, dead bacterial components prior to their determination by flame AAS. Various parameters such as pH, amount of adsorbent, eluent type and volume, flow rate of solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH values of quantitative sorption for Cu and Cd were found to be 7.0 and 7.5, respectively. These metal ions can be desorbed with 1 M HCl (recovery, 96–100%). The sorption capacity of the resin was 0.0297 and 0.035 mmol g −1 for Cu 2+ and Cd 2+, respectively. The tolerance limit of some electrolytes were also studied. This procedure was applied to Cu 2+ and Cd 2+ determination in aqueous solutions, including river and well water systems. In order to evaluate the accuracy of the proposed procedure, the certified reference materials, NRCC-SLRS-4 Riverine water and LGC7162 Strawberry leaves were analyzed.

Synthesis, characterization, and analytical applications of 1,3-dimethyl-4-acetyl-2-pyrazolin-5-one

The synthesis of a new chelating reagent, 1,3-dimethyl-4-acetyl-2-pyrazolin-5-one (DMAP), is described. The reagent is characterized by physical, spectral and thermal methods. The reagent is soluble in water and forms neutral, water-soluble complexes with a number of metal ions, including Zr(IV), Th(IV), and U(VI). The complexed metal ions can be concentrated from dilute aqueous solution by adsorption onto a small column of Amberlite XAD-4 resin. The synthesis and characterization of the uranium (VI) complex of DMAP are described. The complex has the formula UO 2 (DMAP) 2, with a logarithmic formation constant of 8.64. A procedure is given for concentrating trace levels of U(VI) from solution by complexation with DMAP and sorption on XAD-4 resin. The method shows good recovery and precision for the concentration of trace U(VI) from artificial seawater.

Xenobiotic metabolism of p‐nitrophenol derivatives by the rice field crayfish (procambarus clarkii)

AbstractThe extent and routes of metabolism affect the bioconcentration and toxicity of xenobiotics in crayfish. To investigate the in vivo xenobiotic metabolism of three p‐nitrophenol derivatives, rice field crayfish were exposed to 0.1 to 0.01 mg L−1 14C‐substrate solutions for 15 h. At apparent steady‐state uptake, the crayfish were transferred to a recycling flow‐through metabolism chamber for 24 h where the depurated products were collected and concentrated on a column of Amberlite XAD‐4 resin. The tissue absorption and distribution of 14C‐compounds at the apparent steady‐state and post depuration periods were measured by complete tissue combustion and recovery of evolved 14CO2. The structure and concentration of metabolites in resin and soft tissue extracts were determined by cochromatography with authentic standards in HPLC and TLC systems. The crayfish rapidly absorbed the radiolabeled chemicals from solution and depurated metabolites of oxidation and conjugation reactions. The most prominent metabolites were the β‐D‐glucosides of the free phenols, with lesser amounts of the corresponding sulfate esters. Observed oxidations included O‐demethylation, aromatic sidechain oxidation and phosphorothioate deesterification. Body burdens of the original p‐nitrophenol derivatives were markedly reduced by the presence of these metabolic transformations.

Resin Hemoperfusion for Drug Intoxication - An Update

Hemoperfusion through Amberlite XAD-4 resin column has been shown to effectively remove sedative-hypnotics, analgesics and other drugs causing acute intoxication. There is no appreciable clinical toxicity and dramatic shortening of coma time and possible decrease in mortality may be achieved. Thrombocytopenia and clotting may be diminished by pre-perfusion coating with 2.5% albumin. Albumin coating may facilitate the repeated use of hemoperfusion without any complications. More recently, resin hemoperfusion has been used for procainamide, N-acetylprocainamide and theophylline intoxication achieving exceptionally high clearance rates.

Inhibition of seedling growth of crop species by recirculating root exudates ofBidens pilosa L.

The allelopathic effects of root exudates ofBidens pilosa L. on seedling growth ofLactuca sativa L.,Phaseolus vulgaris L.,Zea mays L., andSorghum bicolor (L.) Moench were studied using a root exudate recirculating system that allows continuous exposure of crop plants to allelopathic chemicals. This system maintains an undisturbed rhizosphere and eliminates competition and physical contact between the donor and acceptor plants. Comparison of responses to hydrophobic and hydrophilic root exudates is made possible by removal of hydrophobic compounds using XAD-4. Treatments consisted ofB. pilosa, B. pilosa with an Amberlite XAD-4 resin column attached to the donor pot to remove hydrophobic allelochemicals, and a donor pot without weeds.B. pilosa significantly inhibited seedling growth of all crop species tested. The crop species varied in response to the root exudates, withL. sativa being most sensitive. Larger and olderB. pilosa plants caused greater inhibition of seedling growth ofL. sativa andP. vulgaris than did smaller (younger)B. pilosa plants.B. pilosa with XAD-4 caused significantly less inhibition to all crop species, exceptZ. mays, thanB. pilosa without XAD-4, indicating that the hydrophobic exudates played an important role in the allelopathic growth inhibition. Variability in species response toB. pilosa with and without XAD-4 was probably due to differences in sensitivity to hydophobic and hydrophilic allelochemicals.

Resin Hemoperfusion For Acute Drug Intoxication

To the Editor.— In his latest contribution to the study of the treatment of severe drug intoxication, Dr Rosenbaum and associates 1 described ten hemoperfusions performed on eight patients. The procedure used a 650-gm column of Amberlite XAD-4 resin and was shown to be more effective than any known method of removing barbiturates and glutethimide from the blood of patients with drug overdoses. Previous publication by Rosenbaum and associates dating back to 1970 2-5 have established that this macroreticular resin is effective in the treatment of drug overdose with methaqualone, ethchlorvynol, and all intermediate and long-acting barbiturates or combinations thereof. No clinical data have been published regarding the effectiveness of this resin in the treatment of patients with meprobamate intoxication. We recently were asked to see a 35-year-old woman who had ingested 20 gm of meprobamate 12 hours prior to her transfer to Memorial Medical Center. During those first 12 hours

Resin hemoperfusion for acute drug intoxication

Eight patients with drug intoxication were hemoperfused on ten occasions at a blood-flow rate of 300 ml/min with a 650-gm column of Amberlite XAD-4 resin, which is a macroreticular resin with a specific adsorptive attraction for lipid-soluble organic molecules. Column clearances of glutethimide and a variety of barbiturates ranged from 207 to 300 ml/min for treatment sessions extending from 2 1/2 to ten hours. After ingestion of 75 gm of glutethimide, one patient received hemoperfusion on three successive days for nine, ten, and eight hours, respectively. She recovered after the column removed over 30 gm of drug. The patients demonstrated dramatic clinical responses with no evidence of meaningful toxic reactions. Column hemoperfusion with Amberlite XAD-4 resin was simpler and more effective than any known method of removing barbiturates and glutethimide from the blood of patients with drug overdoses. (<i>Arch Intern Med</i>136:263-266, 1976)

Resin Hemoperfusion for Acute Drug Intoxication

Eight patients with drug intoxication were hemoperfused on ten occasions at a blood-flow rate of 300 ml/min with a 650gm column of Amberlite XAD-4 resin, which is a macroreticular resin with a specific adsorptive attraction for lipid-soluble organic molecules. Column clearances of glutethimide and a variety of barbiturates ranged from 207 to 300 ml/min for treatment sessions extending from 2 1/2 to ten hours. After ingestion of 75 gm of glutethimide, one patient received hemoperfusion on three successive days for nine, ten, and eight hours, respectively. She recovered after the column removed over 30 gm of drug. The patients demonstrated dramatic clinical responses with no evidence of meaningful toxic reactions. Column hemoperfusion with Amberlite XAD-4 resin was simpler and more effective than any known method of removing barbiturates and glutethimide from the blood of patients with drug overdoses.