ResearchPDF Available

Synthesis and chemical and structural characterization of hydroxyapatite obtained from eggshell and tricalcium phosphate

Authors:

Abstract and Figures

This study reports an experimental methodology for the synthesis of hydroxyapatite from eggshell taking into consideration a variation in the content of CaO and tricalcium phosphate Ca3(PO4)2, in order to find the parameters that generate a high content of crystalline hydroxyapatite.
Content may be subject to copyright.
83
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
INGENIERÍA DE MATERIALES
Synthesis and chemical and structural characterization of
hydroxyapatite obtained from eggshell and tricalcium phosphate
MATERIALS ENGINEERING
Síntesis y caracterización química y estructural de hidroxiapatita
sintetizada a partir de cáscara de huevo y fosfato tricálcico
Alejandro Arboleda*, Manuel Franco*, Julio Caicedo**,*, Liliana
Tirado***, Clara Goyes*§
*Universidad Autónoma de Occidente. Cali, Colombia.
**Facultad de Ingeniería Universidad del Valle, Cali-Colombia.
***Universidad del Quindío. Armenia, Colombia.
alejandro.arboleda@outlook.com, mfranco9009@hotmail.com, jcaicedoangulo1@gmail.com,
litirado@uniquindio.edu.co, §cegoyes@uao.edu.co
(Recibido: Abril 24 de 2015 – Aceptado: Agosto 20 de 2015)
Resumen
La cáscara de huevo es un residuo común que generalmente se desecha sin darle uso alguno. En este trabajo
se presenta una metodología experimental que usa la cáscara de huevo para obtener un biocerámico muy
conocido en el campo de la ingeniería de los materiales y la biomédica, llamado hidroxiapatita (HA). La
HA es un fosfato de calcio, su fórmula química es Ca10(PO4)6(OH)2 y tiene características físico-químicas
muy similares a la del hueso humano, lo cual la convierte en uno de los biomateriales más usados como
injertos o sustitutos para reparación ósea. Este material generalmente tiene un alto costo y se presenta en
forma micro y nanoestructurada, ta última, la opción en nanotecnología más promisoria para la ingeniería
de tejidos. La caracterización en este estudio incluye difracción de rayos X, en donde los difragtogramas
obtenidos permiten la identicación de hidroxiapatita, con fase cúbica fcc (111), (102), (211), y la fase
hexagonal hcp (h-211) y (h-322). Por otro lado se presentan resultados de espectroscopia infrarroja con
transformada de Fourier, en donde se determinaron los modos activos de vibración correspondientes a la
hidroxiapatita. Finalmente, mediante microscopia electrónica de barrido se observó la topografía del polvo
cerámico así como también la distribución morfológica obtenida.
Palabras Clave: Biocerámicas, cáscara de huevo, hidroxiapatita, regeneración ósea.
Abstract
The eggshell is a common residue that is usually discarded without giving any use to it. In this paper the
results obtained from a proposed procedure to get hydroxyapatite (HA) from eggshell are shown. The HA
is a calcium phosphate which has been widely used as implant material due to the close similarity of its
composition with the inorganic phase of natural bone. HA generally has a high cost and it is presented
as micro and nanostructured bioceramics; the last one is a promising option for tissue engineering
nanotechnology. In this study, results of X-ray diffraction (XRD) showed the hydroxyapatite production
exhibiting the characteristic peaks of this material for the cubic phase fcc (111), (102), (211), and for the
hexagonal phase hcp (h-211) and (h-322). From the results of Fourier transform infrared spectroscopy
(FTIR), it was possible to determine the active modes of vibration corresponding to hydroxyapatite (Ca10
(PO4)6(OH)2). From the results of scanning electron microscopy, it was determined the topography of the
ceramic powder as well as its morphological distribution.
Keywords: Bioceramics, bone regeneration, eggshell, hydroxyapatite.
84
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
1. Introduction
The eggshell is considered as residue and it is made
up of calcium carbonate (94%), calcium phosphate
(1%), magnesium carbonate (1%), and organic
matter (4%) (Stadelman, 2000). The eggshell is
basically unused after the production of the egg and
its derivates. In the literature, there are few reports
on the use of this residue and the companies that
generate it, considering it as an industrial residue
that might contribute to pollution, since it favors
the microbial proliferation in the environment
(Rivera et al., 1999). As an important source of
calcium carbonate, the eggshell has been used
as raw material in different elds of materials
engineering, particularly as biosensor and in
medicine (Balaz, 2014). In the biomedical eld,
there are some reports showing that the eggshell
has been used in the manufacture of bioceramics
to repair bone injuries (Rivera et al., 1999; Lee &
Oh, 2003). In Colombia, this residue is discarded
and it is not common to nd scientic alternatives
that promote its reuse; this is why this study is
aimed at exploring an alternative of use for the
manufacturing of a type of bioceramics, with the
purpose of contributing to the biomedical eld, in
case its production is optimized. In order to have
an idea of the yearly production of eggshell in
Colombia, it is estimated in 11’529.250 units in
2014, being Valle (Departments of Cauca, Nariño,
and Valle del Cauca) the second most productive
region at national level, with an estimate of
2’972’388 units in 2014 (FENAVI, 2014). At
national level, 691,756 tons were produced
(FENAVI, 2014).
The material that will be produced, known as
hydroxyapatite (HA), has a structure composed
of calcium, phosphorus, and hydroxyl ions
(Ca10(PO4)6(OH)2). Its biological importance
is due to its capacity of allowing a perfect
osseointegration, the absence of local and systemic
toxicity, and the null genotoxic activity (Ginebra
et al., 2006; Franco et al., 2014). HA associates
with the surrounding bone in a tight and stable
way, both chemically and physically, allowing the
repairing processes develop as if they were two
bone tissues in close contact (Ginebra et al., 2006).
Recent publications have demonstrated that HA
at nanostructured scale increases signicantly the
biocompatibility and bioactivity of the man-made
biodevices (Sadat-Shojai et al., 2013). Therefore,
this study includes the comparison of the product
obtained with commercial nano-hydroxyapatite,
with the purpose of nding similar characteristics
that lead to its optimization. One of the reported
sources to synthesize HA is the eggshell (Rivera
et al., 1999; Lee & Oh, 2003), which comprises
processes that take place in a high temperature
environment and using phosphate solutions
(Rivera et al., 1999; Balázsi et al., 2007; Lee &
Oh, 2003). In these reports, the obtaining of HA
has been done from precursors, either tricalcium
phosphate, Ca3 (PO4)2 (Rivera et al., 1999) or
phosphoric acid, H3PO4 (Balázsi et al., 2007; Lee
& Oh, 2003). In the case of tricalcium phosphate
(TCP), it has been reported for producing HA in
an already established relation of Ca/P (Rivera et
al., 1999) but it is recommended to optimize the
composition of the solutions used, the time, and
the temperature of annealing (Rivera et al., 1999).
This study reports an experimental methodology
for the synthesis of hydroxyapatite from eggshell
taking into consideration a variation in the content
of CaO and tricalcium phosphate Ca3(PO4)2, in
order to nd the parameters that generate a high
content of crystalline hydroxyapatite.
2. Methodology
The process for manufacturing hydroxyapatite
(HA) starts with an eggshell mechanic milling
stage to get a white powder. A rst stage of heating
eggshells at 450°C for two hours is carried out
in order for the organic residue to be destroyed
and CaCO3 to be obtained (Rivera et al., 1999).
In this study, the particle grain size was taken into
consideration; therefore, a sieving was done using
different lter sizes starting from an average grain
size of 54 µm up to 74 µm. Afterwards, a heat
treatment of calcium carbonate powder CaCO3
was done during two hours at 900°C, using a Type
30400 Thermolyne furnace in order to ensure its
transformation into CaO through the release of
carbon dioxide (CO2), as presented in Ec. 1.
CaCO3 → CO2 + CaO (1)
85
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
Then, HA is obtained using the precursors tricalcium
phosphate (Ca3(PO4)2, calcium oxide CaO and
water (H2O), as described in Ec. 2.
3Ca3(PO4)2+CaO+H2OCa10 (PO4)6(OH)2
(2)
In this work, an experimental study for
manufacturing HA was carried out; in it, particle
size, temperature ramp, and concentration of
precursors are varied, as shown in Table 1.
Figure 1 shows a ow chart that summarizes the
experimental methodology used in this study.
Sample No. Sieve
size
Ramp of
temperature
[CaO] [Ca3(PO4)2]
Final temperatures of
thermal treatment
Timing
M1 54 µm 10 °C/min 95 % 5 % 1060 °C 7 h
M2 54 µm 10 °C/min 85% 15 % 1060 °C 7 h
M3 54 µm 10 °C/min 75% 25% 1060 °C 7 h
M4 54 µm 10 °C/min 50% 50% 1060 °C 7 h
M5 74 µm 15 °C/min 95 % 5 % 1060 °C 7 h
M6 74 µm 15 °C/min 85% 15 % 1060 °C 7 h
M7 74 µm 15 °C/min 75% 25% 1060 °C 7 h
M8 74 µm 15 °C/min 50% 50% 1060 °C 7 h
M9 54 µm 10 °C/min 100% - 900 °C 5 h
M10 74 µm 15 °C/min 100% - 900 °C 5 h
M11 Commercial HA
In order to determine the crystalline structure
of the hydroxyapatite, a Bruker D8 Advance
diffractometer in the coupled mode θ-2θ was used.
The analysis of vibrational mode of the material
were determined through spectroscopy in the
infrared with Fourier transform (FTIR) through a
Shimadzu 8000 spectrometer (550 – 1000 cm-1) in
transmittance mode, which uses a ceramic source
Nerst type. The spectra of FTIR and diffractograms
of X-ray, for all the cases are compared with
commercial nano-hydroxyapatite samples,
known as FLUIDINOVA - nanoXIM-HAp202.
The morphology of the samples was observed
Figure 1. Summary of the process used
to obtain hydroxyapatite from eggshell.
Tabla 1. Experimental design for obtaining the samples.
86
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
through a Scanning Electron Microscope
(SEM) FEI QUANTA 200, equipped with an
optical light that has a magnifying range of
525-24,000 X and a high sensibility detector
(multi-mode) for dispersion electrons.
3. Results and discussion
3.1 Analysis of infrared spectroscopy
In the spectra obtained through FTIR, numerous
transmission bands in the region of near and
middle infrared can be observed; however, the
most relevant are associated with the vibrations
corresponding to P-O, Ca-O y O-H. Figure 2a
shows the FTIR spectra of the M1 and M4 samples,
corresponding to the hydroxyapatite obtained
with different percentages of CaO, with particle
size 54 µm, heating rate 10ºC/min, at a sintering
temperature 1060 ºC and 7 hours; for comparison
purposes, the spectrum of the commercial sample
is included. When we analyze Figure 2a, an active
vibration mode is found around 571 cm-1 and 601
cm-1 for bonds O–P–O of HA exion type (v4),
which are moderately visible for spectra of the
samples of HA obtained from eggshell. On the
other hand, it is visible when compared to the
commercial sample, a transmittance band around
1415 cm-1 regarding to C-O of CO32- stretching
type (Siriphannon et al., 2002). The spectrum
of the commercial sample presents a band in
3570 cm-1 corresponding to the groups O-H of
symmetric stretching according to the reports
by Siriphannon and Delgado (Siriphannon et al.,
2002; Delgado et al., 1996). This band is also
moderately evident for the samples manufactured
for this study. The vibration centered in the
band of 3570 cm-1 corresponds to O-H bonds of
stretching type (Pramanik et al., 2005). Figure 2b
shows the band of absorbance around 1080 cm-1
of the FTIR spectrum in the sample of commercial
nano-hydroxyapatite. These results allow
determining the contribution corresponding to the
symmetrical stretching type P-O bonds of HA (v3)
(Siriphannon et al., 2002) and to the secondary
phase vibrations such as O-Ca-O, Ca-O, P-O and
Ca-O-P, which characterize hydrated calcium
phosphates and synthesized hydroxyapatite with
the stoichiometric relation of Ca10 (PO4)6(OH)2.
Figure 2. Spectra of FTIR (the graphs have been displaced in the transmittance scale to improve their
comprehension): (a) Hydroxyapatite obtained with different percentages of CaO, with particle size
of 54 µm, heating ramp of 10°C/min, at a sintering temperature of 1060°C and 7 hours (M1-M4),
and commercial nano-hydroxyapatite. (b) Deconvolution of the absorbance spectrum FTIR with high
resolution in the region between 800 cm-1 and 1400 cm-1.
(a) (b)
87
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
Figure 3 shows the spectra of samples M5 to M8
corresponding to the hydroxyapatite obtained
with different percentages of CaO, with
particle size of 74 µm, heating ramp of 15°C/
min, under a sintering temperature of 1060°C
and 7 hours. Additionally, it is presented a
spectrum of commercial nano-hydroxyapatite
in which the band around 1080 cm-1 associated
to the transition corresponding to the O-P-O
bonds HA exion type (v4) (Siriphannon et al.,
2002) are mainly identied. Analyzing Figure
3, it is very clear the presence of an active
mode of vibration around 571 cm-1 and 601
cm-1 corresponding to the O-P-O bonds of HA
exion type (v4) (Siriphannon et al., 2002).
The vibration centered in the band of 3670 cm-1
corresponds to the OH- bonds of stretching type
(Pramanik et al., 2005).
Figure 3. Spectra of FTIR (the graphs have been
displaced in the transmittance scale to improve their
comprehension): Hydroxyapatite obtained with
different percentages of CaO, with particle size of
74 µm, heating ramp of 15°C/min, under a sintering
temperature of 1060°C and 7 hours (M5-M8),
and commercial nano-hydroxyapatite.
Figure 4 shows the spectra of samples M9
and M10 corresponding to the hydroxyapatite
obtained with different heating ramps of 10°C/
min and 15°C/min, a fixed percentage of CaO
100%, with particle size of 54 µm and 74 µm,
under a sintering temperature of 900°C and 5
hours; additionally, it is presented a spectrum
of commercial nano-hydroxyapatite in which
the band around 1080 cm-1 associated to the
transition corresponding to the O-P-O bonds HA
exion type (v3) already described (Siriphannon
et al., 2002) is presented. Figure 4 shows the
vibration centered in the band of 3670 cm-1
corresponding to the O-H bonds of stretching
type (Pramanik et al., 2005). A transition band
around 1415cm-1 which corresponds to the C-O
stretching type of CO32- (Pramanik et al., 2005)
present in the sample is shown as well.
Figure 4. FTIR spectra for the hydroxyapatite
obtained with different heating ramps of (10°C/min),
a xed percentage of CaO 100%, with particle size
of 54 µm and 74 µm, under a sintering temperature
of 900°C and 5 hours (M9, M10) (the graphs have
been displaced in the transmittance scale to improve
its understanding), and spectrum of the sample of
commercial nano-hydroxyapatite.
On the other hand, in Figure 4 it is evident a
signicant reduction in the signal associated
to the bands around 1080 cm-1 compared to the
previous spectra. The gure shows an active
mode of vibration around 571 cm-1 and 601 cm-1
for the O–P–O exion type bonds of HA (v4), as
well as a transition band around 1415 cm-1 related
to the symmetrical stretching type C-O of CO32-
(Siriphannon et al., 2002). The vibration centered
in the band of 3670 cm-1 corresponds to the bonds
O-H- of stretching type (Delgado et al., 1996).
88
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
3.2 X ray diffraction
A characterization through X ray diffraction
for the commercial HA (Ca10(PO4)6(OH)2) was
conducted to determine its structural nature. It is
compared to the X-ray diffractograms obtained
for the samples synthesized from solid residues
of eggshells. International patterns of indexation
taken from the JCPDF 01-074-0565 database
obtained from the “Inorganic crystal structure
database” (ICSD) were considered for the X-ray
diffraction analysis. Figure 5 shows the X-ray
diffractograms obtained for the samples that are
between M1 and M4 with different percentages
of CaO, with particle size of 54 µm, heating ramp
of 10°C/min, under a sintering temperature of
1060°C and 7 hours of treatment.
15 30 45 60 75 90
Si-331
420
422
511
HA-101
HA-110
HA-002
HA-211
HA-202
HA-220
HA-222
HA-321
HA-104
HA-210
HA-502
HA-520
HA-323
HA-006
HA-130
Intensity (u. a.)
2θ
ο
Commercial
CaO 95%
CaO 85%
CaO 75%
CaO 50%
54 µm
10 °C/min
(o)
Figure 5. X-ray diffraction pattern for the hydroxyapatite
obtained with different percentages of CaO, with particle
size of 54 µm, heating ramp of 10°C/min, under a
sintering temperature of 1060°C and 7 hours (M1 –
M4). The diffraction pattern of the commercial nano-
hydroxyapatite sample is included.
Figure 6 shows the X-ray diffractograms obtained
for the samples that are between M5 and M8 with
different percentages of CaO, with particle size
of 74 µm, heating ramp of 15°C/min, under a
sintering temperature of 1060°C and 7 hours of
treatment. It can be analyzed from Figures 5 and 6
that the main peaks characteristic of the hexagonal
Hydroxyapatite with spatial group P63/m-176
appeared. The characteristic phases with the
high intensity crystallographic planes (110),
(210), (202), (220), (222), (321) y (104),
among others, are observed. It is also seen that
while the percentage of CaO decreases for both
sample groups, different crystallographic planes
appeared, which could imply defunctionalization
of the conjugated complexes conforming the
hydroxyapatite. For the particular case of CaO
50% the diffractograms of both samples (M4 and
M8) show variations in position and intensity
from the diffraction maximum values, suggesting
the emergence of secondary phases.
15 30 45 60 75 90
Si-331
420
422
511
HA-101
HA-110
HA-002
HA-211
HA-202
HA-220
HA-222
HA-321
HA-104
HA-210
HA-502
HA-520
HA-323
HA-006
HA-130
Intensity (u. a.)
2θ
ο
Commercial
CaO 95%
CaO 85%
CaO 75%
CaO 50%
74 µm
15 °C/min
(o)
Figure 6. X-ray diffraction pattern for the Hydro-
xyapatite obtained with different percentages of CaO,
with particle size of 74 µm, heating ramp of 15°C/min,
under a sintering temperature of 1060°C and 7 hours
M5 – M8). The diffraction pattern of the commercial
nano-hydroxyapatite sample is included.
3.3 Scanning electron microscopy
Figure 7 shows two micrographs obtained by
scanning electron microscopy (SEM) for a sample
of hydroxyapatite (Ca10(PO4)6(OH)2) synthesized
from solid residues of eggshells. Sample M1
presents morphology of irregular grains forming
agglomerates. The images show that the particles
present an irregular shape, with size close to 10
μm, forming agglomerate until forming groups
of 50 μm. These agglomerates are due to the
porogenic agent in the manufacturing
89
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
process of the samples, which is strongly related
to the molecular formation registered in the
vibrational modes of the HA, analyzed in the
FTIR results (Figs. 2 – 4) and the corresponding
present phases observed by the results of the
X-ray diffraction (Figs. 5 and 6). Additionally,
the particle surface in the synthesized HA has
high roughness. This result is signicant since
the particle shape and its geometry can be
determinant in the nal response at the moment of
the biomaterial implanting.
Figure 7. SEM micrography for ceramic
powder of HA obtained from eggshell.
4. Conclusions
The results of the X-ray diffraction conrm the
synthesis of hydroxyapatite (HA) obtained from
eggshell, due to the presence of constituent
phases of the (HA). For the M4 and M8 samples a
percentage equal to 50% of the CaO and Ca3(PO4)2
components is taken into account. The results
presented show the diffractions corresponding
to the crystallographic planes of the cubic and
hexagonal structures, forming a mixture of phases
of the Ca, PO4 y (OH)2 components, with small
quantities of beta-tricalcium phosphate. Active
modes of vibration corresponding to the CO3
bonds and vibrational bands associated to PO4
were also determined.
5. Acknowledgements
This work has been developed thanks to the support
of the seedbed of Research in Advanced Materials
for Micro and Nanotechnology (IMAMNT) of
the Universidad Autonoma de Occidente, to the
technological support of the Interdisciplinary
Institute of Sciences (IIC) of the Universidad del
Quindio, and to the Center of Excellence in New
Materials (CENM) of the Universidad del Valle.
6. References
Balaz, M. (2014). Eggshell membrane biomaterial
as a platform for applications in materials science.
Acta Biomaterialia 10 (9) 3827–3843.
Balázsi, C., Wéber, F., Kövér, Z., Horváth, E.
& Németh, C. (2007). Preparation of calcium-
phosphate bioceramis from natural resources.
Journal of the European Ceramic Society 27 (2-
3), 1601-1606.
Delgado, A., Paroli, R., & Beaudoin, J. (1996)
Comparison af IR techniques for the characterization
of construction cement minerals and hydrated
products. Applied Spectroscopy 50, 970-976.
90
Ingeniería y Competitividad, Volumen 18, No. 1, p. 69 - 71 (2016)
Ginebra, M.P., Traykova, T., & Planell, J.A.
(2006). Calcium phosphate cements as bone drug
delivery systems: a review. Journal of Controlled
Release 113 (2), 102–110.
Franco, G.R., Laraia, I.O., Maciel, A.A., Miguel,
N.M., Dos Santos, G.R., Fabrega-Carvalho,
C.A., Pinto, C.A., Pettian, M.S. & Cunha, M.R.
(2013) Effects of chronic passive smoking on
the regeneration of rat femoral defects lled with
hydroxyapatite and stimulated by laser therapy.
Injure 44 (7), 908 – 913.
FENAVI (2014). Producción público. [ONLINE]
Available at: http://www.fenavi.org/index.
php?option=com_content&view=article&id=247
2&Itemid=1330#. [Last Accessed 19 Abril 2015].
Lee, S.J., & Oh, S.H. (2003). Fabrication of
calcium phosphate bioceramics by using eggshell
and phosphoric acid. Materials Letters 57 (29).
4570–4574.
Sadat-Shojai, M., Khorasani, M., Dinpanah-
Khoshdargi, E. & Jamshidi, A. (2013). Synthesis
methods for nanosized hydroxyapatite with
diverse structures. Acta Biomaterialia 9 (8),
7591–7621.
Rivera, E.M., Araiza, M., Brostow, W.,
Castaño, V.M., Díaz-Estrada, J.R., Hernández,
R. & Rodríguez, J.R. (1999) Synthesis of
hydroxyapatite from eggshells. Materials Letters
41 (3), 128-134.
Siriphannon, P., Kameshima, Y., Yasumori, A.,
Okada, K., & Hayashi, S. (2002). Formation of
hydroxyapatite on CaSiO3 powders in simulated
body uid. Journal of the European Ceramic
Society 229 (4), 511-520.
Pramanik, S., Agarwaly, A.K. & Rai K.N. (2005).
Development of High Strength Hydroxyapatite
for Hard Tissue Replacement. Trends Biomater.
Artif Organs 19 (1), 46-51.
Revista Ingeniería y Competitividad por Universidad del Valle se encuentra bajo una licencia Creative
Commons Reconocimiento - Debe reconocer adecuadamente la autoría, proporcionar un enlace a la
licencia e indicar si se han realizado cambios. Puede hacerlo de cualquier manera razonable, pero no
de una manera que sugiera que tiene el apoyo del licenciador o lo recibe por el uso que hace.
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
Hydroxyapatite (HAp) is a suitable bioceramic material for hard tissue replacement. In this present work HAp has synthesized by solid state reactions in temperature near 1250°C and it exhibits hexagonal crystal structure. HAp samples exhibited improvement in mechanical properties with increasing cold compaction pressure as well as recrushing operation. It also showed high resistance to surface reaction with the simulated body fluid. Surface morphology, pore volume, and particle size of the material have studied by Scanning Electron Microscopy, Brunauer-Emmett-Teller technique, and Particle Size Analysis. Chemical bonding present in the newly produced hydroxyapatite material was confirmed by Fourier Transform Infrared Spectrometry.
Article
Full-text available
Defects associated with bone mass loss are frequently treated by autogenous bone grafting. However, synthetic biomaterials such as calcium phosphate ceramics can substitute autologous grafts as long as they are biocompatible with bone tissue. In addition, low-level laser therapy (LLLT) is used to enhance bone regeneration by stimulating the local microcirculation and increasing the synthesis of collagen by bone cells. However, bone health is fundamental for osseointegration of the graft and bone repair. In this respect, excessive tobacco consumption can compromise expected outcomes because of its deleterious effects on bone metabolism that predispose to the development of osteoporosis. The objective of this study was to evaluate the regeneration of bone defects implanted with biomaterial and stimulated by LLLT in rats submitted to passive cigarette smoking. Porous hydroxyapatite granules were implanted into critical-size defects induced experimentally in the distal epiphysis of the right femur of 20 female Wistar rats submitted to passive smoking for 8 months in a smoking box. The defect site was irradiated with a gallium-arsenide laser at an intensity of 5.0J/cm(2). The animals were divided into four groups: control (non-smoking) rates submitted (G2) or not (G1) to laser irradiation, and smoking rats submitted (G4) or not (G3) to laser irradiation. The animals were sacrificed 8 weeks after biomaterial implantation. The right femurs were removed for photodocumentation, radiographed, and processed for routine histology. The results showed good radiopacity of the implant site and of the hydroxyapatite granules. Histologically, formation of new trabecular bone was observed adjacent to the hydroxyapatite granules in G1 and G2. In G3 and G4, the granules were surrounded mainly by connective tissue. In conclusion, passive smoking compromised bone neoformation in the defects and the LLLT protocol was not adequate to stimulate local osteogenesis.
Article
Full-text available
The influence of FT-IR sampling techniques on the characterization of cement systems was investigated. Three FT-IR techniques were used to study tricalcium silicate (C3S), hydrated C3S, calcium hydroxide, and calcium silicate hydrate (C-S-H). They include transmission spectroscopy (TS), photoacoustic spectroscopy (PAS), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The TS technique (using KBr pellets) was the most labor-intensive but was found to give the simplest spectra with well-defined bands. The PAS technique was found to be the simplest technique but yielded bands at lower wavenumber than TS. DRIFTS was determined to be a good alternative for cement powders since it provided spectra similar to those for the TS technique. DRIFTS required more sample preparation than PAS but less sample preparation than the KBr pellet technique.
Article
Eggshell membrane is an unique biomaterial, which is generally considered waste. However, it has extraordinary properties which can be utilized in various fields and therefore its potential applications are widely studied in these days. In the first part of this review, the chemical composition and morphology of the ESM is the main issue. The main fields of ESM applications are discussed in the second part. They include its utilization as abiotemplate for the synthesis of nanoparticles,sorbent of heavy metals, organics, dyes, sulfonates and fluorides, the main component of biosensors, the material applicable in medicine and afew other. For each area of interest, adetailed literature survey is given.
Article
Hydroxyapatite (HAp) is the major mineral constituent of vertebrate bones and teeth. It has been well documented that HAp nanoparticles can significantly increase the biocompatibility and bioactivity of man-made biomaterials. Over the past decade, HAp nanoparticles have therefore increasingly been in demand, and extensive efforts have been devoted to develop many synthetic routes, involving both scientifically and economically new features. Several investigations have also been made to determine how critical properties of HAp can be effectively controlled by varying the processing parameters. With such a wide variety of methods for the preparation of HAp nanoparticles, choosing a specific procedure to synthesize a well-defined powder can be laborious; accordingly, in the present review, we have summarized all the available information on the preparation methodologies of HAp, and highlighted the inherent advantages and disadvantages involved in each method. This article is focused on nanosized HAp, although recent articles on microsized particles, especially those assembled from nanoparticles and/or nanocrystals, have also been reviewed for comparison. We have also provided several scientific figures and discussed a number of critical issues and challenges which require further research and development.
Article
CaSiO3 powders were prepared from ethanol solutions of Ca(NO3)2·4H2O and Si(OC2H5)4 using NaOH as a precipitant. The resultant powders were heated at three different temperature regimes, (1) 500°C, (2) 500 and 1000oC and (3) 500 and 1400°C, to obtain the amorphous phase (amorphous-CS), low temperature phase (β-CS), and high temperature phase (α-CS) of CaSiO3, respectively. The different amorphous and crystalline phases exhibited different microtextures and specific surface areas of the powders. The rough, porous particles of amorphous-CS and β-CS have higher specific surface areas than the smooth, dense particles of α-CS. These CaSiO3 powders were soaked in a simulated body fluid (SBF) at 36.5°C for 2 h to 30 days. Formation of hydroxyapatite (HAp) was observed on the surfaces of all samples, but the formation behavior and microstructures were different, resulting the differences in microstructure and crystal structure of the starting powders as well as particle size and specific surface area. The HAp formed on the amorphous-CS was a loose porous layer consisting of uniformly-sized tiny ball-like agglomerated particles, while that formed on the β-CS and α-CS was a dense layer consisting of larger ball-like agglomerated particles.
Article
Pure and highly sinterable hydroxyapatite (HAp) and β-tricalcium phosphate (β-TCP) ceramics were successfully fabricated by using recycled eggshell and phosphoric acid. The observed phases on the powder synthesis process were dependent on the mixing ratio (wt.%) of the calcined eggshell and phosphoric acid, and the calcination temperature. The HAp and β-TCP were stably synthesized in the 1:1.1–1:1.2 and 1:1.3–1:1.5 mixing ratios, respectively. Ball-milled β-TCP powder showed fine particles and was fully densified (having β-phase) by sintering at 1200 °C for 2 h. The crystalline development and microstructures of the synthesized powders and densified β-TCP were examined by X-ray diffractometry and scanning electron microscopy, respectively.
Article
A novel procedure to produce porous hydroxyapatite (HAp) from eggshells is reported. The process is carried out at an elevated temperature. HAp is the only apatite present in the reaction products, apart from minute fractions of certain other calcium compounds. The final product is characterized by X-ray diffraction and scanning electron microscopy (SEM).
Article
In this study, calcium phosphate based bioceramics have been synthesised by using eggshell derived raw materials and phosphoric acid at different mixing ratios. Development of the elaboration processes has been conducted to gain mono phase hydroxyapatite (HAP). The processing route of calcium phosphate ceramics and the end product characteristics have been found to be influenced by acid/CaO mixing ratio, milling time and heat treatment applied. Calcium phosphate foams resulted at higher acid/CaO mixing ratio with high specific surface area. At higher sintering temperatures, calcium phosphate thin and thick film coatings have been produced by a condensation method. The films contained a mixture of micron size crystals and nanofibrous cover layer. The good adherence of films to the calcium phosphate substrate assured a higher strength for these samples.
Article
Since calcium phosphate cements were proposed, several formulations have been developed, some of them commercialised, and they have proven to be very efficient bone substitutes in different applications. Some of their properties, such as the injectability, or the low-temperature setting, which allows the incorporation of different drugs, make them very attractive candidates as drug carriers. In this article, the performance of calcium phosphate cements as carriers of different types of drugs, such as antibiotics, analgesics, anticancer, anti-inflammatory, as well as growth factors is reviewed.