XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
90
T3: O–9
Octavinyl and ctaphenyl silsesquioxane thin films
Bartosz Handke
1
, and Natalia Gębicka
1
1
AGH University of Science and Technology, Faculty of Material Science and Ceramics, Al.
Mickiewicza 30, 30-059 Kraków, Poland, e-mail: bhandke@agh.edu.pl
The cage shaped molecules with empirical formula (RSiO
1,5
)
n
in which R stands for organic
substituent called polyhedral oligomeric silsesquioxane (POSS) are recently intensively studied
among many hybrid, organic-inorganic materials. The inorganic core, based on Si-O bonds
provides excellent thermal and mechanical stability and the organic substitute provide desire
functionality of the POSS molecule. The well-defined molecular structure makes POSS
molecules a perfect candidate for the nano blocks in design of the new materials. In our studies,
we focused on cubic shaped POSS molecules with vinyl or phenyl organic groups attached at
each corner. In terms of electronic properties both, phenyl and vinyl groups are closely related,
because of sp
2
hybridized carbon atoms. Moreover, both silsesquioxane crystalize well in form
of molecular crystals. Nevertheless, as thin films, thus material with broken symmetry, vinyl and
phenyl POSS exhibit extremely different growth behavior and thin film structures.
Thin films were fabricated by means of molecular beam deposition techniques under UHV
conditions. Clean silicon wafers were used as a template for thin film growth. In order to fully
investigate the structure and morphology, research has been based on X-Ray Reflectivity
spectroscopy, Grazing Incidence X-Ray Diffraction and Atomic Force Microscopy.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
91
T3: O–10
Spectroscopic studies of nanocomposite ceramic layers
Aleksandra Wesełucha-Birczyńska
1
, Elżbieta Długoń
2
, Jan Pukalski
1
,
Wiktor Niemiec
2
, and Marta Błażewicz
2
1
Faculty of Chemistry, Jagiellonian University, Ingardena 3, Krakow, Poland, e-mail:
birczyns@chemia.uj.edu.pl
2
Faculty of Materials Science and Ceramics, AGH-University of Science and Technology,
Mickiewicza 30, 32-043 Kraków, Poland
Discovery and introduction of new or improved materials and nanomaterials stimulate the
progress in medical diagnosis, and therapy [1]. For biomaterials the most important attribute is their
biofunctionality and biocompatibility, which means type and character of the interaction with host
cells and fluids [2].
Two types of novel nanocomposite layers, produced using the electrophoretic deposition, have
been tested. The base for both layers was stainless steel. First nanocomposite layer was constructed of
nano-hydroxyapatite (nHAp) covered with a layer of carbon nanotubes (CNTs), and the second of
carbon nanotubes (CNTs) covered with nano-silica layer (nSiO
2
). The layers were tested by
incubating them for 21 days in simulation body fluid (SBF) solution. Additionally as a target a human
serum albumin (HSA) was used to check the the interaction of the protein with surface. The
incubation periods set to: 2 min, 5 min, 10 min and 15 min, allowed us to estimate the dynamics of
the interfacial interaction between nanomaterial and protein surfaces.
A Renishaw inVia Raman micro-spectrometer, connected to a Leica microscope, was used for the
measurements of the Raman spectra. The 514.5 nm beam from an Ar
+
ion laser was focused on a
samples by 100× magnifying, a high numerical aperture (NA=0.9) Leica objective. Atomic force
microscopy (AFM), performed on a Bruker atomic force microscope MultiMode 8, was used to image
the outer atomic layers of the studied surfaces.
The degree of crystallinity of studied layers, as D1/G Raman bands intensity ratio, was estimated
[3]. It is equal to 1.06±0.02, 1.16±0.02, and 1.33±0.02 for reference CNTs layer, nHAp/CNT and
nHAp/CNTs/SBF sample, respectively. The layers with nano-silica show cystallinity parameter equal
to 1.06±0.02, 0.656±0.02, and 0.59±0.02 for reference CNTs layer, CNTs/nSiO
2
and
CNTs/nSiO
2
/SBF sample, respectively. Obtained data show the significant effect of the nanoceramic
layer crystallinity of the nanocomposite surfaces and consequently on hydroxyapatite nucleation.
Another parameters useful to estimate the degree of organization on the surface is
D1/(G+D1+D2) area ratio (R2 ratio) [3]. R2 is equal to 0.55±0.01, 0.56±0.01, and 0.66±0.01 for
reference CNTs layer, nHAp/CNTs and nHAp/CNTs/SBF sample, respectively. R2 parameter is
equal to 0.55±0.01, 0.44±0.02, and 0.38±0.02 for reference CNTs layer, CNTs/nSiO
2
and
CNTs/nSiO2/SBF sample, respectively. There is observed an increase of disorder in the plane for
nHAp /CNTs, while the increase in order for the CNTs/nSiO
2
layer.
The interaction of the surface of both nanomaterials with the HSA protein leads to a significant
decrease in crystallinity. These data as well as AFM images specify kinetics of both proteins
deposition ratio.
Keywords: Carbon nano-tubes (CNT); nHAp; nSiO
2
; Raman microspectroscopy; AFM
Acknowledgment
This project was financed from the National Science Centre (NCN, Poland) granted on the decision number DEC-
2013/09/B/ST8/00146 and UMO-2014/13/B/ST8/01195.
References
[1] W.M. Saltzman, Biomed. Eng., Bridging Medicine and Technology, 2nd ed., Cambridge Univ. Press,
Cambridge, 2015.
[2] Biological and Biomedical Coatings Handbook: Applications, S. Zhang (Ed.), CRC Press, 2011.
[3] O. Beyssac, B. Goffe, J.-P. Petitet, E. Froigneux, M. Moreau, J.-N. Rouzaud, Spectrochim. Acta A 59 (2003)
2267.
[4] A. Wesełucha-Birczyńska, E. Stodolak-Zych, Sylvia Turrell, F. Cios, M. Krzuś, E. Długoń, A. Benko,
W.Niemiec, M. Błażewicz, Vib. Spectrosc., 85 (2016) 185–195.
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