Surface functionalization of natural hydroxyapatite by polymerization of β-cyclodextrin: application as electrode material for the electrochemical detection of Pb(II)

Abstract

A composite material prepared by polymerization of β-cyclodextrin (β-CD) on the surface of natural hydroxyapatite using citric acid as cross linker, was employed as electrode material for the detection of Pb(II). Hydroxyapatite was obtained from bovine bones, following a three-step procedure including precalcination, chemical treatment with (NH 4 ) 2 HPO 4 and calcination. The structure of the pristine hydroxyapatite (NHAP P0.5 ) and its functionalized counterpart (NHAP p0.5 -CA-β-CD) materials was examined using XRD and FTIR. Upon deposition as thin lm on a glassy carbon electrode (GCE), the ion exchange ability of NHAP p0.5 -CA-β-CD was exploited to elaborate a sensitive sensor for the detection of lead. The electroanalytical procedure was based on the chemical accumulation of lead ions under opencircuit conditions, followed by the detection of the preconcentrated species using differential pulse anodic stripping voltammetry. The reproducibility of the proposed method based on different measurements in a solution containing 2 µM lead gave a coe cient of variation of 1.27%. Signi cant parameters that can affect the lead stripping response were optimized: a linear calibration curve for lead (II) in the concentration range of 2 × 10 − 8 mol L − 1 − 20 × 10 − 8 mol L − 1 (R 2 = 0.998) was obtained. The detection limit (DL = 3S/M) and the sensitivity of the proposed sensor were 5.06 × 10 − 10 mol L − 1 and 100.80 µA.µM − 1 , respectively. The interfering effect of several ions expected to affect the stripping determination of lead was evaluated, and the proposed sensor was also successfully applied in the determination of Pb 2+ ions in spring water and well water.

Perspective Chapter: Sample Preparation Techniques for Electrochemical Analysis of Pesticides and Heavy Metals in Environmental and Food Samples

“…A practical example of the ASV analysis and control of traces of Pb in drinking water is given in Figure 3. Figure 3A shows the influence of modification of the electrode for the ASV determination of Pb 2+ [25], while Figure 3B shows the influence of the concentration and the calibration curve for the determination of the limit of detection (LOD) of Pb 2+ using the ASV method [26].…”

Hydroxyapatite/L-Lysine Composite Coating as Glassy Carbon Electrode Modifier for the Analysis and Detection of Nile Blue A

“…The resort to these materials aims at improving either the sensitivity or the selectivity of the bare solid electrode. In recent years, the scientific community in analytical electrochemistry has shown great interest in the development of hydroxyapatite-based sensors [29][30][31]. Hydroxyapatite is a low-cost material that can be produced from high calcium phosphate biominerals present, for example, in seashells and animal bones [32,33].…”

“…Along these lines, Kanchana and Sekar [38] proposed an electrochemical sensor of uric acid, based on EDTA/HA nanoparticles. The electroanalysis of both diquat and lead ions was successfully achieved by Tchoffo and coworkers [31,39], using a glassy carbon electrode modified with a hybrid material from HA and β-cyclodextrin.…”