Electrical properties of hydroxyapatite thin films grown by pulsed laser deposition

Hontsu, Shigeki; Matsumoto, Toshirou; Ishii, Junya; Nakamori, Masaya; Tabata, Hitoshi; Kawai, Tomoji

doi:10.1016/s0040-6090(96)09146-8

Cited by 69 publications

(32 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the dielectric constant-porosity relationship found in this study for bulk HAp also holds for thin films, then from Equation (4) and the coefficients listed for 1.641 MHz in Table I 10 but other ceramic thin films fabricated by laser ablation can exhibit high porosities. 22 In addition to the k data for HAp from the Hontsu et al 10 and the Fanovich et al 21 studies, the results of this study may be compared with measurements of k for bone in Marino et al 8 For frequencies of 1 to 100 kHz, Marino et al 8 determined the effect of water content on k for human cortical bone (HCB). For dry HCB with densities of 1.76 g/cm 3 to 1.90 g/cm 3 , k for the HCB ranged from about 5.7 to 6.5, independent of frequency.…”

Section: Dielectric Constant As a Function Of Porosity At Fixed Frequmentioning

confidence: 68%

“…In agreement with what has been observed in many studies of k as a function of P, the MaxwellGarnett mixing law (Eq. 3) gave only relatively broad upper and lower bounds for the k-P data 10 (Fig. 3).…”

Section: Resultsmentioning

confidence: 95%

“…In another study involving the room-temperature measurement of the dielectric constant of HAp, Hontsu et al 10 used a pulsed laser deposition tech- For each data set, the coefficient of determination is given by r 2 . nique to form 1-micron-thick films of HAp onto various substrates.…”

Section: Dielectric Constant As a Function Of Porosity At Fixed Frequmentioning

confidence: 99%

“…10 Such coatings could be useful not only in applications in which biocompatibility is an asset (as would be the case for implantable devices), but more generally as a dielectric material to electrically insulate other devices.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The porosity dependence of the dielectric constant for sintered hydroxyapatite

Hoepfner

Case

2002

J. Biomed. Mater. Res.

View full text Add to dashboard Cite

Hydroxyapatite (HAp) is the major mineral constituent of bone, and as such, the dielectric properties of HAp are of interest because electromagnetic fields have been shown to accelerate healing in bone fractures. In addition, an interest in the dielectric properties of HAp stems from the suggestion that electrically insulating HAp coatings might be used on implantable devices. In this study, the dielectric constant of polycrystalline hexagonal HAp was measured at nine different frequencies, from 45 kHz to 7.3 MHz for relative porosities ranging from 0.05 to 0.42. At a fixed frequency, the decrease in k as a function of increasing porosity is described well by an exponential function of porosity such that k = k(0)exp(-bP), where k(0) is the dielectric constant at zero porosity and b is a constant. In addition, the entire data set of 108 data points (representing the 12 specimens of differing porosity measured at each of the nine frequencies) was fit to a candidate function formed from the product k(0)exp(-bP) and a simple expression relating frequency to the dielectric constant. The candidate function fit the data relatively well, with a coefficient of determination of 0.91.

show abstract

Section: Dielectric Constant As a Function Of Porosity At Fixed Frequmentioning

confidence: 68%

Section: Resultsmentioning

confidence: 95%

Section: Dielectric Constant As a Function Of Porosity At Fixed Frequmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The porosity dependence of the dielectric constant for sintered hydroxyapatite

Hoepfner

Case

2002

J. Biomed. Mater. Res.

View full text Add to dashboard Cite

show abstract

“…An initial step to consider such application would be investigation of electrical properties of hydroxypatite coating. The properties, including dielectric constant, loss tangent and breakdown voltage were investigated for 1 lm thin HA film obtained by pulsed laser deposition (PLD) [2]. Similar properties of nanosized HA obtained by ball milling were tested by Silva et al [3].…”

Section: Introductionmentioning

confidence: 99%

Optimization of Dielectric Properties of Suspension Plasma Sprayed Hydroxyapatite Coatings

Jaworski

Pierlot

Tomaszek

et al. 2007

Materialwissenschaft Werkst

View full text Add to dashboard Cite

Conventional plasma torch was adapted to spray very fine Ca 5 (PO 4 ) 3 OH (hydroxyapatite, HA) precursors having sizes ranging from a few hundreds of nanometers to a few micrometers. The powders were put in suspension with distilled water and antidispersive agent. A home made suspension feeder, including two peristaltic pumps, delivered the suspension into atomizer and therefrom injected into plasma jet. The suspension flow rate was electronically controlled. The resulting coatings had the thickness of a few tenths of lm. The electrical properties of the coatings including breakdown voltage and loss factor of suspension sprayed hydroxyapatite coatings sprayed onto aluminium substrates were also tested.The influence of such experimental factors as power input to plasma, pressure of atomizing gas, spray distance and suspension feed rate on the responses being the electrical properties was investigated using a 2 4 design of experiments (DOE). The mathematical models relating the responses with the factors were created and the significant factors were selected.

show abstract

In vitro stability predictions for the bone/hydroxyapatite composite system

Oppermann

Crimp

Bement³

1998

J. Biomed. Mater. Res.

View full text Add to dashboard Cite

Electroacoustic measurements of the zeta (zeta) potential as a function of pH were collected and used to probe the nature of the ionic contributions to the bond formed between synthetic hydroxyapatite (HA) and bone. HA powder and wet bone powder were dispersed into an electrolyte solution comprised of physiologic saline (0.154M NaCl), electroacoustic measurements collected, and the zeta potential calculated as a function of pH. The zeta potential and particle size then were used to calculate the stability of the composite dispersion, where stability is the ability of a particulate suspension to remain unagglomerated. The stability was used to predict the homo- (HA to HA and bone to bone) versus heterocoagulation (HA to bone) behaviors for the HA/bone system. Although single component bone and HA demonstrated stability against agglomeration, the HA/bone interaction was determined to be unstable for all pH levels tested, including pH 7.4, the normal in vivo pH. These results establish one factor responsible for the observed physicochemical bonding between bone and HA noted by many in the orthopedic community.

show abstract

Electrical properties of hydroxyapatite thin films grown by pulsed laser deposition

Cited by 69 publications

References 11 publications

The porosity dependence of the dielectric constant for sintered hydroxyapatite

The porosity dependence of the dielectric constant for sintered hydroxyapatite

Optimization of Dielectric Properties of Suspension Plasma Sprayed Hydroxyapatite Coatings

In vitro stability predictions for the bone/hydroxyapatite composite system

Contact Info

Product

Resources

About