Preparation of iminodiacetic acid functionalized multi-walled carbon nanotubes and its application as sorbent for separation and preconcentration of heavy metal ions.
In this paper, a novel material was prepared with functionalizing multi-walled carbon nanotubes (MWCNTs) using iminodiacetic acid (IDA) and characterized by FT-IR. Isotherm and kinetics of adsorption were studied and the experimental data fitted the Langmuir model and pseudo-second-order equation very well. An on-line method for simultaneous determination of trace V (V), Cr (VI), Pb (II), Cd (II), Co (II), Cu (II) and As (III) in biological samples was developed using this material as sorbent coupled with inductively coupled plasma mass spectrometry (ICP-MS). A series of experimental parameters, including sample pH, sample flow rate and loading time, eluting solution and the effect of interfering ions have been investigated systematically. Under the optimum experimental conditions, the enrichment factors for above metal ions were ranged from 66 to 101. Detection limit (3 s) was achieved at 1.3, 1.2, 0.70, 0.40, 2.5, 3.4, 0.79 ng L(-1), respectively. At the 1.0 μg L(-1) level, the precision (RSD, %) for 11 replicate measurements was from 1.0 to 4.0. In spiked biological samples, good recoveries (n=3) were obtained in the range of 90-110%. These results had proved that the proposed method was with good accuracy and could be applied to the analysis of trace metal ions in biological samples.
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science & Technology, Tianjin 300457, China.
Junping
J
Wang
Xiaoxing
X
Ma
Guozhen
G
Fang
Mingfei
M
Pan
Xiaoke
X
Ye
Shuo
S
Wang
D000327:Adsorption; D000465:Algorithms; D006863:Hydrogen-Ion Concentration; D007098:Imino Acids / Q000138:chemical synthesis / Q000737:chemistry*; D007202:Indicators and Reagents; D007700:Kinetics; D019216:Metals, Heavy / Q000032:analysis*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D052616:Solid Phase Extraction; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics
D007098:Imino Acids; D007202:Indicators and Reagents; D019216:Metals, Heavy; D037742:Nanotubes, Carbon; C008109:iminodiacetic acid