Influence of doping chromium ions on the electrical properties of hydroxyapatite

Abstract

Hydroxyapatite Ca 10 [PO 4 ] 6 [OH] is a biocompatible widely used in medicine and dentistry. Its applications depend greatly upon lattice substitution of Calcium sites in its structure by varies cations such as Na, Mg, Sr, Ag etc. Chromium plays an important role in reducing blood sugar level and improving insulin ability to convert glucose in cells to gain energy. In this paper we studied the effect of doping hydroxyapatite with chromium ions on its crystal dielectric properties. Pure hydroxyapatite and chromium loaded hydroxyapatite of chromium concentrations of 0.5, 1.0, 2.0, and 3.0 wt % forming samples S1, S2, S3 and S4 respectively were prepared by wet precipitation method. The dielectric parameters, permittivity ἐ, dielectric loss ἕ, conductivity σ, relaxation time t s and dielectric modulus M' and M'' were calculated at frequency of 20 Hz to 10 MHz. Results showed increase of ἐ, and ἕ, values of chromium loaded samples compared to pure hydroxyapatite. The conductivity of the doped samples was increased with chromium concentration increase. The relaxation times (t s ) chromium loaded samples showed increase of t s as chromium concentration increase. The dielectric properties showed that as chromium concentration increase, ἐ, ἕ, and σ of substance increase compared to the pure HA.

The Effect of Doping on the Electrical and Dielectric Properties of Hydroxyapatite for Medical Applications: From Powders to Thin Films

“…Compared with undoped HA, the Cr-doped HA (100 • C) samples displayed higher conductivity in the low-frequency region, merging with undoped HA's conductivity at approximately 10 6 Hz. This increase in HA conductivity due to Cr doping suggested an improvement in its bio-conductivity, which confirmed the successful incorporation of Cr ions into the HA structure [53]. In their study, Iqbal et al [169] evidenced that the effective conductivity of undoped HA exhibited a tendency to increase with the applied frequency, displaying a dispersive behavior at low applied frequencies.…”

“…It is known that, in patients with diabetes, the concentration of Cr tends to decrease. Additionally, Cr plays a vital role in augmenting insulin action, improving carbohydrate metabolism, and reducing insulin resistance [53][54][55]. Moreover, the corrosion and adhesion outcomes, coupled with the minimal release rate of Cr ions into Ringer's solution, could pave the way for advancements in the assessment of immune cell activation and other biocompatibility tests, which are crucial for diverse medical implant applications of Cr oxide coatings [56].…”

Correlation between positron annihilation lifetime and photoluminescence measurements for calcined Hydroxyapatite

“…It is also possible to convert it into a magnetic nanocomposite, which has potential uses in biomedical fields 6 . Doping HAp with transition metal ions such as chromium can enhance its electrical properties 7 . Furthermore, the optical properties of HAp can vary depending on several factors, including synthesis conditions 8 .…”

Impact of Dopants on the Electrical and Optical Properties of Hydroxyapatite

“…Further, the annealed iron-doped HAp revealed ferromagnetism, whereas the manganese and cobalt ions doped samples exhibited super-paramagnetic property [7]. The dielectric properties of the chromium-doped HAp were also studied [8]. Various anions such as nitrate, acetate, chloride, and egg shell precursors have been used to prepare HAp particles and their corresponding dielectric constant were 9.96, 13.22, 9.92, and 10.86 at 5 MHz [9].…”