Modern methods of Ta₂O₅ coatings deposition for biomedical applications
The study of e-beam evaporated Ta₂O₅ film structure and properties effect on cell/material response was performed. The surface properties and structure of e-beam evaporated Ta₂O₅ films were investigated by means of XPS and XRD methods. The cytotoxicity and cytocompatibility were estimated by in...
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| Zitieren: | Modern methods of Ta2O5 coatings deposition for biomedical applications / N. Donkov, A. Zykova, V. Safonov, E. Mateev // Вопросы атомной науки и техники. — 2009. — № 1. — С. 153-155. — Бібліогр.: 8 назв. — англ. |
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nasplib_isofts_kiev_ua-123456789-886442025-02-09T13:10:09Z Modern methods of Ta₂O₅ coatings deposition for biomedical applications Сучасні методи нанесення покриттів Ta₂O₅ для бiомедичного застосування Современные методы нанесения покрытий Ta₂O₅ для биомедицинского применения Donkov, N. Zykova, A. Safonov, V. Mateev, E. Низкотемпературная плазма и плазменные технологии The study of e-beam evaporated Ta₂O₅ film structure and properties effect on cell/material response was performed. The surface properties and structure of e-beam evaporated Ta₂O₅ films were investigated by means of XPS and XRD methods. The cytotoxicity and cytocompatibility were estimated by in vitro tests. Films of Ta₂O₅ are bio- and chemically inert, which allows their use in various medical applications, e.g., in diagnostic and treatment techniques employing short-range quasi-static electric fields for stimulation of positive biological processes in live organisms. Дослідження структури та властивостей покриттiв Ta₂O₅, які нанесено методом електронно-променевого випарювання, було зроблено методами рентгеноструктурного аналізу та фотоелектронної спектроскопії. Цитотоксичнiсть i цiтосумiснiсть були визначені in vitro. Плiвки Ta₂O₅ мають бiо- та хімічно- інертні властивості, що сприятиме їх застосуванню з метою діагностики та лікування з використанням близькодіючих квазiстацiонарних електричних полів, якi стимулюють позитивні біологічні процеси. Исследования структуры и свойств покрытий Ta₂O₅, нанесенных методом электронно-лучевого испарения, были проведены методами рентгеноструктурного анализа и фотоэлектронной спектроскопии. Цитотоксичность и цитосовместимость были определены in vitro. Пленки Ta₂O₅ являются био- и химически- инертными, возможно их применение для диагностики и лечения с использованием близкодействующих квазистационарных электрических полей, стимулирующих позитивные биологические процессы. The work was fulfilled due to financial support from the Bulgarian Academy of Science and National Academy of Science of Ukraine collaboration program. 2009 Article Modern methods of Ta2O5 coatings deposition for biomedical applications / N. Donkov, A. Zykova, V. Safonov, E. Mateev // Вопросы атомной науки и техники. — 2009. — № 1. — С. 153-155. — Бібліогр.: 8 назв. — англ. 1562-6016 PACS: 87.80 Rb https://nasplib.isofts.kiev.ua/handle/123456789/88644 en Вопросы атомной науки и техники application/pdf Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Низкотемпературная плазма и плазменные технологии Низкотемпературная плазма и плазменные технологии |
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Низкотемпературная плазма и плазменные технологии Низкотемпературная плазма и плазменные технологии Donkov, N. Zykova, A. Safonov, V. Mateev, E. Modern methods of Ta₂O₅ coatings deposition for biomedical applications Вопросы атомной науки и техники |
| description |
The study of e-beam evaporated Ta₂O₅ film structure and properties effect on cell/material response was performed.
The surface properties and structure of e-beam evaporated Ta₂O₅ films were investigated by means of XPS and XRD
methods. The cytotoxicity and cytocompatibility were estimated by in vitro tests. Films of Ta₂O₅ are bio- and
chemically inert, which allows their use in various medical applications, e.g., in diagnostic and treatment techniques
employing short-range quasi-static electric fields for stimulation of positive biological processes in live organisms. |
| format |
Article |
| author |
Donkov, N. Zykova, A. Safonov, V. Mateev, E. |
| author_facet |
Donkov, N. Zykova, A. Safonov, V. Mateev, E. |
| author_sort |
Donkov, N. |
| title |
Modern methods of Ta₂O₅ coatings deposition for biomedical applications |
| title_short |
Modern methods of Ta₂O₅ coatings deposition for biomedical applications |
| title_full |
Modern methods of Ta₂O₅ coatings deposition for biomedical applications |
| title_fullStr |
Modern methods of Ta₂O₅ coatings deposition for biomedical applications |
| title_full_unstemmed |
Modern methods of Ta₂O₅ coatings deposition for biomedical applications |
| title_sort |
modern methods of ta₂o₅ coatings deposition for biomedical applications |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2009 |
| topic_facet |
Низкотемпературная плазма и плазменные технологии |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/88644 |
| citation_txt |
Modern methods of Ta2O5 coatings deposition
for biomedical applications / N. Donkov, A. Zykova, V. Safonov, E. Mateev // Вопросы атомной науки и техники. — 2009. — № 1. — С. 153-155. — Бібліогр.: 8 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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2025-11-26T02:05:28Z |
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2025-11-26T02:05:28Z |
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| fulltext |
MODERN METHODS OF Ta2O5 COATINGS DEPOSITION
FOR BIOMEDICAL APPLICATIONS
N. Donkov, A. Zykova1, V. Safonov2, E. Mateev
Institute of Electronics, Bulgarian Academy of Sciences, Sofia, Bulgaria,
E-mail: nikolaidd@abv.bg;
1Institute of Surface Engineering, Kharkov, Ukraine;
2NSC „Kharkov Institute of Physics and Technology“, Kharkov, Ukraine
The study of e-beam evaporated Ta2O5 film structure and properties effect on cell/material response was performed.
The surface properties and structure of e-beam evaporated Ta2O5 films were investigated by means of XPS and XRD
methods. The cytotoxicity and cytocompatibility were estimated by in vitro tests. Films of Ta2O5 are bio- and
chemically inert, which allows their use in various medical applications, e.g., in diagnostic and treatment techniques
employing short-range quasi-static electric fields for stimulation of positive biological processes in live organisms.
PACS: 87.80 Rb
1. INTRODUCTION
The interest to dielectric materials and coatings
applications has considerably increased in various areas
of science and technique in recent years. Coatings based
on Ti, Al oxides exhibit unique properties: high
inductivity, density and fusion temperature, together with
high electret characteristics. Tantalum has a high potential
in the biomedical field. Ta-based implants show high
fracture toughness, corrosion and wear resistance,
chemical stability. The results of the animal implantation
test of Ta in both soft and hard tissue of rats showed good
biocompatibility and osteogenesis of this metal [1]. TaC
and TaN materials posses relatively high hardness due to
the covalent nature of their bond [2] and demonstrate high
thermal stability and superior corrosion resistance [3].
The blood compatibility of TaN films was shown to be
better than those of TiN and Ta [4]. Films of Ta2O5 are
also bio- and chemically inert, which allows their use in
various medical applications.
In the paper new Ta pentoxide ceramic coatings are
presented as perspective biomaterials for biomedical
applications like dental implants, coronary stents or
prosthesis. The study of e-beam evaporated Ta2O5 film
structure and properties effect on cell/material response
was performed.
2. MATERIALS AND METHODS
The samples were formed on glass substrates. The
electron beam evaporator consists of a heated tungsten
filament apertured by screen, surrounding the filament
(Fig.1). Both the apertured anode and the crucible are at a
ground potential. Accelerating voltage Ua is applied to the
filament and to the screen. The magnetic field is created
by an electromagnet. The evaporation power Pev needed to
heat the crucible containing the evaporated metal is the
product of the anode current Ia and Ua (7kV).
The evaporation process was carried out at initial
vacuum of 710−6 Torr, operational-mode vacuum of 3
10−5 Torr, anode current of 50 mA and calculated
evaporation power of 350 W [5]. The layer thickness and
the deposition rate were controlled by a digital thin-film
deposition monitor MSV-1843/H MIKI-EEV operating at
6 MHz. The deposition rate at those conditions was
50 nm/min. The control module consists of: a control
unit, a pulse time modulator, a ramp generator and a final
control element (FCE).
Fig.1. Electron beam evaporator: control unit, pulse time
modulator, ramp generator and final control element
The surface properties and structure of e-beam
evaporated Ta2O5 films were investigated by means of
XPS and XRD methods. X-ray photoelectron
spectroscopy was carried out using ESCALAB MkII (VG
Scientific) electron spectrometer at a base pressure in the
analysis chamber of 5x10-10 mbar (during the
measurement 1x10-8 mbar), using AlKalpha X-ray source
(excitation energy hn=1486.6 eV). The instrumental
resolution measured as the full width at a half maximum
(FWHM) of the Ag3d5/2, photoelectron peak is 1 eV. The
energy scale is corrected to the C1s - peak maximum at
285 eV for electrostatic charging.
The analysis of surface parameters such as
wettability, surface free energy was made. The contact
angles were measured by Wilhelm’s method in Kruss
K12 Tensiometer at temperature 20o C [6]. For next
calculations of surface free energy (SFE) were used the
values of advancing water contact angle by Roberson
equation, which is in a good agreement with values
obtained by means of Owens-Wendt-Rabel-Kaeble’
method.
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2009. № 1. 153
Series: Plasma Physics (15), p. 153-155.
The experiments on study of cytotoxicity and
cytocompatibility in vitro – in culture of fibroblasts were
carried out [7]. In process of cell cultivation with coated
samples the cell cytology, morphology and proliferation
activity were determined by means of optical microscopy
after 24h and 3, 5 days cultivation. Rat hypodermic
cellular tissue was extracted for initial fibroblast culture
obtaining. The suspension of extracted cells was
centrifuged at 750 orb/min during 15 min. Sowing cell
area was 3x105 cell/ml density of cultural medium. The
fibroblast cultivation at 3 ml of Dulbecco Modified
Eagle’s Medium (DMEM, Sigma) was made by methods
of mono layer culture at thermostat condition
(temperature 37o C during 5 days). After cultivation,
fixation at the acetic acid and methyl alcohol (1:3)
solution and azure-eosin coloration the cellular
proliferation on the cover glasses was determined by
optical microscopy (Micros). The experiments were
triplicate.
3. RESULTS AND DIDCUSSION
The XPS survey spectra of the e-beam evaporated
Ta2O5 films (initial, un annealed sample; sample annealed
at 450oC in O2) were obtained. All spectra consist of well
defined XPS lines of Ta 4f, 4d, 4p and 4s; O 1s; C 1s. All
binding energies of the high-resolution spectra were
calibrated with a C 1s binding energy of 285.0 eV. Fig. 2
show the high-resolution Ta4f and 4 O1s XPS spectra of
the investigated structures.
50 45 40 35 30 25 20 15 10 5
0
2000
4000
6000
8000
10000
12000
14000
16000
C
PS
binding energy (eV)
Y3686DA_TA4F.A1
Y3696DA_TA4F.A1
Y3700DA_TA4F.A1
Y3756DA_TA4F.A1
545 540 535 530 525 520 515
2000
4000
6000
8000
10000
12000
14000
16000
18000
20000
22000
24000
C
PS
binding energy (eV)
Y3686DA_O1S.A1
Y3696DA_O1S.A1
Y3700DA_O1S.A1
Y3756DA_O1S.A1
Fig. 2 The XPS high-resolution Ta 4f and 4 O 1s spectra
of the e-beam evaporated Ta2O5 films
A relatively strong C1s feature is observed at 285 eV
for the precursor and deposited films, most likely as a
result of hydrocarbon adsorptions on the samples surfaces
due to the exposure after the deposition to atmosphere
air.(In situ surface cleaning using an ion –gun was not
applied, in order to avoid the negative effects of the
sputtering on the film composition). The carbon signal
was used to take account the effect of the samples
charging during the measurements.
Ta 4f doublets are typical for e-beam evaporated
Ta2O5 and have two peaks: Ta 4f7/2 at ~ 26.3…26.6 eV
and Ta 4f5/2 at the binding energy 1.9 eV higher. The Ta
4f lines of the deposited films agree well with the Ta 4f
doublet representative of the Ta-0 bond in Ta2O5. The
Ta4f7/2 peak is placed at 26.5 and 26.6 eV, and the Ta
4f5/2 one is at 28.4 and 28.5 eV for the annealed and un
annealed films respectively. These results clearly
demonstrate that the annealed films are more
stoichiometric Ta2O5 composition. The O1s spectra
further support this assumption. The O 1s peaks of the
deposited layers are centered at binding energies of 530.9
and 530.8 eV for the for the annealed and un annealed
films respectively, which is consistent with reported data
for Ta205 [8]. The FWHM of both peaks is 1.9 eV. The
O/Ta ratio estimated from the spectra is ~ 3 for all
samples (see Table bellow).
The wettability of films was evaluated by Wilhelm’s
method in Kruss K12 Tensiometer at temperature 20o C.
The e-beam evaporated Ta2O5 films exhibited contact
angles ranging from 49.3±0.5° for un annealed film to
52.5±0.6° for annealed film. The value of contact angle
about 50° is considered as a positive indicator of good
cell attachment, spreading and proliferation. In our study
the values of water contact angle were measured in the
range 49…52o, and evaluated by expression [6] meaning
of SFE were in the range 40…45 mN/m.
After 3 days staying in the culture. fibroblast cells were
well spread both on the control and coated surfaces. Any
statistically significant dependence in the average area of
cultivated cell was observed. The cell morphology was
typical for cells on the coated surface. The cell structural
organization corresponded to initial fibroblast. After 5
days cultivation the density of cell increased for all
samples.
The concentration of O1s and Ta4f and binding energy
annealed, un annealed and initial samples obtained from
XPS spectra
The most of cells were ripe fibroblasts with strongly
marked phenotype. Fibroblast cells were well spread at all
coated surfaces. The effect of the surface properties on
cell proliferation is investigated by counting the cells
attached to the glass surfaces after incubation. The mean
cell counts vary when compared to uncoated glass
samples (control, n = 72): cell numbers decrease by 18%
154
Samples C, at.%
O 1s
C,
at.%
Ta4f
Ta/
/O
ratio
Binding
energy E
(eV)
O 1s
Binding
energy E
(eV)
Ta 4f
Initial 68 32 0.471 530.4 26.3
Anneal. at
450 oC 69 31 0.449 530.9 26.5
Un anneal. 74 26 0.361 530.8 26.6
for un annealed film (n= 59) and by 11% for annealed
e-beam evaporated Ta2O5 film (n = 64). The results
demonstrated the good biocompatibility of e-beam
evaporated Ta2O5 coatings especially in the case of
annealed films with stoichiometric Ta2O5 composition.
4. CONCLUSIONS
The results show that the surface properties are
strongly influenced by the preliminary treatment and the
deposition conditions. The XPS analysis results clearly
demonstrate that the annealed films are more
stoichiometric Ta2O5 composition. The O/Ta ratio
estimated from the spectra was ~ 3 for un annealed and
initial samples (see Table), The e-beam evaporated Ta2O5
films exhibited contact angles, ranging from 49.3±0.5° for
un annealed film to 52.5±0.6° for annealed film and
evaluated meaning of SFE were in the range 40-45
mN/m. The cyto toxicity and cyto compatibility of Ta2O5
films were estimated by in vitro tests. The cell
morphology was typical for cells on the coated surface.
The results demonstrated the good biocompatibility of e-
beam evaporated Ta2O5 coatings especially in the case of
annealed films with stoichiometric Ta2O5 composition.
The deposition process controlling allows one to control
the surface parameters of the e-beam evaporated Ta2O5
films and the next positive biological response of live
organisms.
ACKNOWLEDGEMENT
The work was fulfilled due to financial support from
the Bulgarian Academy of Science and National
Academy of Science of Ukraine collaboration program.
REFERENCES
1.H. Matsuno, A. Yokoyama, F. Watari, M. Uo,
T. Kawasaki //Biomaterials. 2001, v.22, p.1253.
2.T. Miyazaki, H.-M. Kim, T. Kokubo, C. Ohtsuki,
H. Kato, T. Nakamura//Biomaterials. 2002,v. 23, p.827.
3.G. Georgeiv, N. Fescheschiev, D. Popov, Z. Uzuuov //
Vacuum. 1986, v.36, p. 595.
4.Y.X. Leng, H. Sun, P. Yang, J.Y. Chen, J. Wang,
G.J. Wan, N. Huang, X.B. Tian, L.P. Wang, P.K. Chu //
Thin Solid Films. 2001, v. 398/399, p. 471.
5.Z. Todorova, N. Donkov, Z. Ristic, N. Bundaleski,
S. Petrovic, M. Petkov. Electrical and optical
characteristics of Ta2O5 thin films deposited by electron-
beam vapor deposition // J. Plasma process and polymers.
2006, v. 3/2, p. 174-178.
6.A. Zykova, V. Safonov, V. Luk’yan-chenko,
J. Walkowicz, R. Rogowska. The influence of surface
parameters of coatings deposited by various vacuum
plasma methods on the cell / material interection in vitro
tests // Problems of Atomic Science and Technology.
Series “Plasma Physics” (13). 2007, N 1, p.200-203.
7.Marshal Dhayal, Su-In Cho, Jun Young Moon, Su-Jin
Cho, Anna Zykova. S180 cell growth on low ion energy
plasma treated TiO2 thin films // J. Applied Surface
Science. 2008, v. 254, p. 3331-3338.
8.V. Georgieva, L. Spassov, D. Spassov, N. Donkov,
P. Petkov. Tantalum pentoxide –based quartz crystal
microbalance for NH3 detection//J. of optoelectronics and
advanced materials. 2007, v. 9, N 2, p. 252-255.
Article received 8.10.08
СОВРЕМЕННЫЕ МЕТОДЫ НАНЕСЕНИЯ ПОКРЫТИЙ Ta2O5
ДЛЯ БИОМЕДИЦИНСКОГО ПРИМЕНЕНИЯ
Н. Донков, Е. Матеев, А. Зыкова, В. Сафонов
Исследования структуры и свойств покрытий Ta2O5, нанесенных методом электронно-лучевого испарения,
были проведены методами рентгеноструктурного анализа и фотоэлектронной спектроскопии. Цитотоксичность
и цитосовместимость были определены in vitro. Пленки Ta2O5 являются био- и химически- инертными, возмож-
но их применение для диагностики и лечения с использованием близкодействующих квазистационарных элек-
трических полей, стимулирующих позитивные биологические процессы.
СУЧАСНІ МЕТОДИ НАНЕСЕННЯ ПОКРИТТІВ Ta2O5
ДЛЯ БIОМЕДИЧНОГО ЗАСТОСУВАННЯ
Н. Донков, Е. Матеев, Г. Зикова, В. Сафонов
Дослідження структури та властивостей покриттiв Ta2O5, які нанесено методом електронно-променевого
випарювання, було зроблено методами рентгеноструктурного аналізу та фотоелектронної спектроскопії.
Цитотоксичнiсть i цiтосумiснiсть були визначені in vitro. Плiвки Ta2O5 мають бiо- та хімічно- інертні
властивості, що сприятиме їх застосуванню з метою діагностики та лікування з використанням близькодіючих
квазiстацiонарних електричних полів, якi стимулюють позитивні біологічні процеси.
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