A solid-phase method for the quantitation of protein in the presence of sodium dodecyl sulfate and other interfering substances

Because of its superior surface properties, nanocalcium carbonate can be applied to the adsorption of heavy metals in wastewater. However, because of the easy aggregation of nanocalcium carbonate, high surface energy and poor dispersibility in water, it is not conducive to the process of adsorption. Therefore, surface modification of nanocalcium carbonate is needed. In this paper, nanocalcium carbonate was prepared by liquid phase method. And the nanocalcium carbonate was surface modified by sodium dodecyl sulfate. The effects of modifier amount, modification temperature, and modification time on the activation and absorbance of nanocalcium carbonate were investigated. And the morphology and particle size of modified nanocalcium carbonate were tested by SEM and XRD patterns.The results show that the dispersion and surface activity of the modified nanocalcium carbonate have been improved remarkably. Moreover, the Cu2+ was adsorbed by sodium dodecyl sulfate modified nanocalcium carbonate and unmodified nanocalcium carbonate under the optimum modification conditions. And the effects of nanocalcium carbonate initial concentration on the adsorption performance were studied. The results show that the adsorption performance of modified calcium carbonate is better than that of the unmodified. Moreover, the adsorption process is studied by adsorption isotherm. By drawing the adsorption isotherms lines and by comparing the fitting result of the experimental data based on the Langmuir model and that of Freundlich model, it is found that the adsorption of Cu2+ by modified nanocalcium carbonate meets the Langmuir model.

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Solid phase extraction of trace amounts of cadmium(II) ions in water and food samples using iron magnetite nanoparticles modified by sodium dodecyl sulfate and 2-mercaptobenzothiazole

Water Science & Technology ◽

10.2166/wst.2017.010 ◽

2017 ◽

Vol 75 (6) ◽

pp. 1440-1446

Author(s):

Shahriar Abbasi ◽

Mehdi ShanbehDehbalai ◽

Hossein Khani

Keyword(s):

Sodium Dodecyl Sulfate ◽

Solid Phase Extraction ◽

Magnetite Nanoparticles ◽

Solid Phase ◽

Sodium Dodecyl ◽

Food Samples ◽

Phase Extraction ◽

Cadmium Ions ◽

Relative Standard ◽

Dodecyl Sulfate

A new, simple and rapid method for solid phase extraction and preconcentration of trace amounts of cadmium ions using 2-mercaptobenzothiazole/sodium dodecyl sulfate immobilized on magnetite nanoparticles (MBT-SDS-MNPs) was proposed. The method is based on the extraction of cadmium ions via complexation with MBT immobilized on SDS-coated MNPs and their determination by flame atomic absorption spectrometry. The effects of different parameters – pH; eluent type, concentration and volume; amounts of salt and adsorbent; contact time and interfering ions – on the adsorption of cadmium ions were studied. Under optimized conditions, the calibration curve was linear in the range of 10–5,000 μg L−1. Detection limit and relative standard deviation of the proposed method were 0.009 μg L−1 and 2.2%, respectively. The adsorption data were analyzed by Langmuir and Freundlich isotherm models and a maximum adsorption amount of 24.80 mg g−1, a Langmuir adsorption equilibrium constant (b) of 4.62 and Freundlich constants Kf and n of 6.075 mg1–1/n L1/n g−1 and 2.391, respectively, were obtained. Finally, this adsorbent was successfully used for extraction of cadmium from water and food samples.

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