Two different glasses, one biocompatible but with a low bioactivity index (G1) and the other with an higher bioactivity index (G2), the ceramic version of the second glass and a titanium alloy (Ti6Al4V) have been functionalizated by anchoring alkaline phosphatase (ALP) on their surfaces. The enzyme has been chosen because it is involved in mineralization processes of hard tissues and is a model for more complex ones. ALP has been grafted on glasses and glass-ceramics surfaces both with and without samples silanization and on metallic surfaces with and without tresyl chloride activation. Samples have been analyzed at each step of the functionalization process in order to verify i

Bianchi, C.

Cassinelli, C.

Ferraris, Sara

Morra, M.

Spriano, Silvia Maria

Verne', Enrica

Vitale Brovarone, Chiara

PORTO Publications Open Repository TOrino

Politecnico di Torino
Porto Institutional Repository
[Proceeding] Surface Functionalisation of biomaterials with alkaline
phosphatase
Original Citation:
Verne’ E.; Ferraris S; Vitale Brovarone C; Spriano S; Bianchi C; Morra M; Cassinelli C (2008).
Surface Functionalisation of biomaterials with alkaline phosphatase. In: Bioceramics 20. pp. 593-
596
Availability:
This version is available at : http://porto.polito.it/1652119/ since: April 2016
Publisher:
Trans Tech
Terms of use:
This article is made available under terms and conditions applicable to Open Access Policy Article
("Public - All rights reserved") , as described at http://porto.polito.it/terms_and_conditions.
html
Porto, the institutional repository of the Politecnico di Torino, is provided by the University Library
and the IT-Services. The aim is to enable open access to all the world. Please share with us how
this access benefits you. Your story matters.
(Article begins on next page)
  
Surface Functionalization of Biomaterials with Alkaline Phosphatase 
 
Enrica Vernè*,a, Sara Ferraris*,b, Chiara Vitale Brovarone*,c, Silvia Spriano*,d, 
Claudia Letizia Bianchi§,e, MarcoMorra#,f, Clara Cassinelli#,g 
 
*Material Science and Chemical Engineering Departement, Turin Politechnich C.so Duca degli 
Abruzzi 24, 10129, Turin, Italy 
§ Dept. Physical Chemistry and Electrochemistry, Milan University, V. Golgi 19, 20133 Milan (Italy) 
#NobilBio Ricerche, V. San Rocco 32, 14018 Villafranca d’Asti (AT) 
aenrica.verne@polito.it, bsara.ferraris@polito.it, cchiara.vitale@polito.it, dsilvia.spriano@polito.it, 
eclaudia.bianchi@unimi.it, fmmorra@nobilbio.it, gccassinelli@nobilbio.it  
Keywords: functionalization, biomimetic surfaces, osteointegration 
 
Abstract 
Two different glasses, one biocompatible but with a low bioactivity index (G1) and the other with 
an higher bioactivity index (G2), the ceramic version of the second glass and a titanium alloy 
(Ti6Al4V) have been functionalizated by anchoring alkaline phosphatase (ALP) on their surfaces. 
The enzyme has been chosen because it is involved in mineralization processes of hard tissues and 
is a model for more complex ones. ALP has been grafted on glasses and glass-ceramics surfaces 
both with and without samples silanization and on metallic surfaces with and without tresyl chloride 
activation. Samples have been analyzed at each step of the functionalization process in order to 
verify it . 
Introduction 
The success of prosthetic surgery is strictly connected to integration between implant and tissue and 
the rapid healing of bad quality bone. In this way an interesting solution is the realization of 
biomimetic surfaces for implants, this means that surface is able to send signals directly to cells in 
order to promote tissue regeneration. A so characterized material is bioactive not only from a 
physicochemical point of view (hydroxyapatite precipitation in simulated body fluid), but also from 
a biological one. 
Bioactive glasses have been widely studied for orthopaedic and dental applications, as coatings on 
metallic substrates or for the realization of small bone substitutes. They have an excellent 
This is the author post-print version of an article published on Key 
Engineering Materials, Vol. 361-363, pp. 593-596, 2007 (ISSN 
1662-9795). 
 
The final publication is available at  
lhttp://www.scientific.net/KEM.361-363.593 
http://dx.doi.org/10.4028/www.scientific.net/KEM.361-363.593 
 
This version does not contain journal formatting and may contain 
minor changes with respect to the published edition. 
 
The present version is accessible on PORTO, the Open Access 
Repository of the Politecnico of Torino, in compliance with the 
publisher’s copyright policy. 
 
Copyright owner: Scientific.net 
 biocompatibility and promote osteoinduction proportionally to their bioactivity index. Titanium 
alloys are extensively employed in prosthetic surgery (orthopaedic and dental implants) because of 
their biocompatibility and good mechanical properties. It could be very interesting for clinical 
application that these materials also be able to send cells signals to promote their adhesion, 
proliferation, differentiation, migration and matrix mineralization. So the aim of this research work 
is the grafting of a biomolecule involved in bone regeneration processes (alkaline phosphatase) to 
their surface. 
Materials and Method 
A glass belonging to the system SiO2-CaO-Na2O-Al2O3 (G1) and one to the system SiO2-P2O5-
CaO-MgO-Na2O-K2O (G2) were prepared through traditional melting and quenching technique. 
Glasses have been poured on brass plate in order to obtain bars then annealed in furnace to relax 
residue tensions. Bars have then been cut and polished to prepare samples. G2 has also thermally 
treated to promote crystallization (G2cer). Ti6Al4V samples have been prepared cutting and 
polishing a metallic bar. 
The firs step in functionalization process is the cleaning of surfaces to remove any contaminants 
and the exposition of hydroxyl groups. As for glasses samples have been washed for 5minutes in 
acetone in an ultrasonic bath for contaminant removing, then they have been washed three times in 
distilled water for 5 minutes in ultrasonic bath. Contact angle measurements have been carried out 
in order to verify OH groups exposition as an increase in surface hydrophilicity. 
As for titanium samples an acid attack and a thermo-chemical treatment have been realized. 
Hydroxyls groups have been observed by means of XPS and FTIR analysis. 
The second step is the introduction of specific functional groups or a surface activation in order to 
promote and stabilize the bonding with enzyme molecule. In this research work the activation 
method selected for glasses is silanization [1] with 3-amminopropyltriethoxysilane, which is 
characterized by amino groups that support biomolecule bonding. Samples have been immersed for 
6 hours in a  solution of silane in ethanol, thermally dried in a furnace (1 hour at 100°C) to stabilize 
bonding between surface hydroxyls and silane molecule, then washed three times in ethanol in 
ultrasonic bath to remove not-bound molecule and finally thermally dried in furnace 1 hour at 
100°C. In order to verify silane grafting on glass surface contact angle measurements and XPS 
analysis have been carried out. In order to analyze the stability of silane-surface bonding some 
samples have been washed in TRIS and then observed. 
As for titanium an activation with Tresyl Chloride has been selected [2,3].  
The last step is alkaline phosphatase grafting. Alkaline phosphatase is a glycoprotein containing 
zinc and magnesium, it is employed in in-vitro tests as a marker for osteoblast differentiation and 
some studies underline that it promote new bone forming and mineralization [4,5]. 
Samples have been incubated in a solution of alkaline phosphatase in PBS for 20 hours at 4°C. 
Reaction has been stopped by a TRIS washing. As for control also samples without silanization 
(treated only for hydroxyl exposition) have been grafted with ALP. Some samples have been 
washed in TRIS in ultrasonic bath after ALP anchoring, in order to investigate bond stability. The 
same grafting process has been applied to both glasses and metal. 
Samples have been then analyzed in order to examine enzyme grafting, by means of XPS and UV-
vis spectroscopy. The first technique studies the chemical elements present on the surface and their 
state, while the second allows to determine enzyme activity. This last test has been carried out by 
dipping functionalized samples in a solution containing p-nitrophenilphosphate, which is 
hydrolyzed by ALP to produce p-nitrophenol which has a yellow coloration, this has been 
quantified by UV-vis spectroscopy. 
   
Results and Discussion 
As for hydroxyls exposition tests show that, as expected, surface became hydrophilic. The initial 
value of contact angle is about 70° and after the different washings it was comprised between 20° 
 and 30° for all glasses and glass ceramics studied. Titanium samples show OH characteristic peaks 
both on XPS detailed analysis of oxygen region and on FTIR spectra. 
As for silanization contact angle measurements exhibit that surface became hydrophobic, values 
change to 70°-80°. Results show also that the bonding is resistant to TRIS washings, in fact contact 
angle values remains unvaried after washings (Fig. 1).  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Fig. 1: Contact angle measurement on silanized samples 
 
XPS spectra on samples surfaces show the appearance of nitrogen peak, characteristic of silane 
amino groups (Table 1). 
FTIR spectra of tresylated titanium exhibit characteristic peaks for C-F vibrations. 
As for enzymatic activity evaluations graphs show that the molecule is anchored in active state to 
the surface of all glasses and glass ceramics tested. After washing the weakly bonded portion of 
ALP is taken off from sample but a significant part remains on surface (Fig. 2). An aliquot of 
enzyme could be grafted also onto not-silanized samples (exploiting OH groups), but the bond is 
weaker, in fact after washings the amount of enzyme that remain on sample’s surface is lower. 
 
Enzymatic activity
0
0,01
0,02
0,03
0,04
0,05
0,06
0,07
0,08
0,09
0,1
Sil-glass+ALP Sil-glass+ALP+wash
ab
so
rb
an
ce G1
G2
G2cer
 
Fig. 2: Enzymatic activity on silanized samples 
 
XPS spectra show an enrichment in carbon and nitrogen  that hide glass constituents on surface of 
functionalized samples (Table 1).  
 
Table 1: XPS data for samples at different step of functionalization process 
Sample O Na N Ca C Si Mg Cl S P 
G1+sil 40.1 0.8 4.1 0.9 32.6 19.5 - - - - 
Silanization
0
10
20
30
40
50
60
70
80
90
100
Sil Sil+wash
Co
n
ta
ct
 
an
gl
e 
[°]
G1
G2
 G1+sil+ALP 23.8 0.8 7.8 - 61.7 - - 4.5 0.3 1.1 
G1 37.1 1.9 - 1.8 49.1 10.1 - - - - 
G1+ALP 23.7 0.8 10.6 - 57.7 - - 6.5 - 0.8 
G2 39.4 1.9 1.8 1.7 32.1 16.7 5.7 - - - 
G2+sil 18.0 2.6 2.6 - 69.9 4.8 1.8 - - - 
G2+ALP 26.5 0.7 9.2 - 57.3 1.6 - 3.6 - 1.1 
G2cer 41.3 1.5 2.0 3.4 31.9 16.4 3.1 - - - 
G2cer+ALP 31.2 0.7 6.7 2.0 46.3 9.6 - 2.3 - 1.3 
G2cer+sil 32.7 2.0 3.5 2.1 46.1 13.0 - - - - 
G2cer+sil+ALP 25.8 0.2 8.7 0.9 53.3 8.6 - 1.3 1.2 - 
 
Besides a detailed analysis of carbon region exhibit a peak characteristic of C-O and C-N bonds 
(286 eV) and a peak related to aromatic rings (292-293 eV) that are a mark of ALP presence. 
It could be noted that on less reactive materials (G1 and G2cer) the bonding with silane and with 
ALP is stronger and more stable, this happens because in this case bioactivity reactions doesn’t 
interfere with bonding processes.  
Similar results have been obtained for metallic samples. Enzymatic activity tests underline that pure 
metallic samples didn’t anchor ALP, hydroxylated ones are able to graft an aliquot of biomolecule 
but a significant amount is anchored only to tresylated samples. As for washing tests results are 
analogous to glasses ones. 
Conclusions 
It is possible to anchor alkaline phosphatase to the surface of glasses and glass-ceramics with 
different degrees of bioactivity, and to titanium alloy (Ti6Al4V). As for glasses the grafting is 
realizable both with and without surface silanization, but silane presence on sample’s surface 
strengthens and stabilizes the bond. 
Enzyme activity is preserved on all materials after anchoring. 
In order to evaluate biocompatibility of functionalized materials and investigate cellular response to 
biological stimuli, in-vitro tests are in progress. 
Both for cellular test and for future clinical applications of this processes, is in progress a study of 
the possibility of sterilize functionalized samples without reducing enzyme activity. 
 
References 
[1]. M. Ma, Y. Zhang, W. Yu, H. Shen, H. Zhang, N. Gu, Colloids and Surface A: Physicochem. 
Eng. Aspects 212, 2003: 219-226 
[2]. D.A.Puleo (1996) Biomaterials 17: 217-222 
[3]. T. Hayakawa, M. Yoshinari, K. Nemoto (2003) Wiley Periodicals Inc.684-688 
[4] M.C. Groeneveld, V Everts, W. Beertsen, J Dent Res 74(7) (1995) 
[5] A. Piattelli, A. Scarano, M. Corigliano, M. Piattelli,  Biomaterials 17 (1996) 
 
 
 


Surface Functionalisation of biomaterials with alkaline phosphatase

Two different glasses, one biocompatible but with a low bioactivity index (G1) and the other with
an higher bioactivity index (G2), the ceramic version of the second glass and a titanium alloy
(Ti6Al4V) have been functionalizated by anchoring alkaline phosphatase (ALP) on their surfaces.
The enzyme has been chosen because it is involved in mineralization processes of hard tissues and
is a model for more complex ones. ALP has been grafted on glasses and glass-ceramics surfaces
both with and without samples silanization and on metallic surfaces with and without tresyl chloride
activation. Samples have been analyzed at each step of the functionalization process in order to
verify it 

VERNE', Enrica

FERRARIS, SARA

VITALE BROVARONE, CHIARA

SPRIANO, Silvia Maria

BIANCHI C

MORRA M

CASSINELLI C.

PORTO@iris (Publications Open Repository TOrino - Politecnico di Torino)

05 August 2020POLITECNICO DI TORINORepository ISTITUZIONALESurface Functionalisation of biomaterials with alkaline phosphatase / VERNE' E.; FERRARIS S; VITALE BROVARONEC; SPRIANO S; BIANCHI C; MORRA M; CASSINELLI C. - 361-363(2008), pp. 593-596. ((Intervento presentato alconvegno Bioceramics 20.OriginalSurface Functionalisation of biomaterials with alkaline phosphatasePublisher:PublishedDOI:Terms of use:openAccessPublisher copyright(Article begins on next page)This article is made available under terms and conditions as specified in the  corresponding bibliographic description inthe repositoryAvailability:This version is available at: 11583/1652119 since: 2016-04-11T10:44:29ZTrans Tech  Surface Functionalization of Biomaterials with Alkaline Phosphatase  Enrica Vernè*,a, Sara Ferraris*,b, Chiara Vitale Brovarone*,c, Silvia Spriano*,d, Claudia Letizia Bianchi§,e, MarcoMorra#,f, Clara Cassinelli#,g  *Material Science and Chemical Engineering Departement, Turin Politechnich C.so Duca degli Abruzzi 24, 10129, Turin, Italy § Dept. Physical Chemistry and Electrochemistry, Milan University, V. Golgi 19, 20133 Milan (Italy) #NobilBio Ricerche, V. San Rocco 32, 14018 Villafranca d’Asti (AT) aenrica.verne@polito.it, bsara.ferraris@polito.it, cchiara.vitale@polito.it, dsilvia.spriano@polito.it, eclaudia.bianchi@unimi.it, fmmorra@nobilbio.it, gccassinelli@nobilbio.it  Keywords: functionalization, biomimetic surfaces, osteointegration  Abstract Two different glasses, one biocompatible but with a low bioactivity index (G1) and the other with an higher bioactivity index (G2), the ceramic version of the second glass and a titanium alloy (Ti6Al4V) have been functionalizated by anchoring alkaline phosphatase (ALP) on their surfaces. The enzyme has been chosen because it is involved in mineralization processes of hard tissues and is a model for more complex ones. ALP has been grafted on glasses and glass-ceramics surfaces both with and without samples silanization and on metallic surfaces with and without tresyl chloride activation. Samples have been analyzed at each step of the functionalization process in order to verify it . Introduction The success of prosthetic surgery is strictly connected to integration between implant and tissue and the rapid healing of bad quality bone. In this way an interesting solution is the realization of biomimetic surfaces for implants, this means that surface is able to send signals directly to cells in order to promote tissue regeneration. A so characterized material is bioactive not only from a physicochemical point of view (hydroxyapatite precipitation in simulated body fluid), but also from a biological one. Bioactive glasses have been widely studied for orthopaedic and dental applications, as coatings on metallic substrates or for the realization of small bone substitutes. They have an excellent This is the author post-print version of an article published on Key Engineering Materials, Vol. 361-363, pp. 593-596, 2007 (ISSN 1662-9795).  The final publication is available at  lhttp://www.scientific.net/KEM.361-363.593 http://dx.doi.org/10.4028/www.scientific.net/KEM.361-363.593  This version does not contain journal formatting and may contain minor changes with respect to the published edition.  The present version is accessible on PORTO, the Open Access Repository of the Politecnico of Torino, in compliance with the publisher’s copyright policy.  Copyright owner: Scientific.net  biocompatibility and promote osteoinduction proportionally to their bioactivity index. Titanium alloys are extensively employed in prosthetic surgery (orthopaedic and dental implants) because of their biocompatibility and good mechanical properties. It could be very interesting for clinical application that these materials also be able to send cells signals to promote their adhesion, proliferation, differentiation, migration and matrix mineralization. So the aim of this research work is the grafting of a biomolecule involved in bone regeneration processes (alkaline phosphatase) to their surface. Materials and Method A glass belonging to the system SiO2-CaO-Na2O-Al2O3 (G1) and one to the system SiO2-P2O5-CaO-MgO-Na2O-K2O (G2) were prepared through traditional melting and quenching technique. Glasses have been poured on brass plate in order to obtain bars then annealed in furnace to relax residue tensions. Bars have then been cut and polished to prepare samples. G2 has also thermally treated to promote crystallization (G2cer). Ti6Al4V samples have been prepared cutting and polishing a metallic bar. The firs step in functionalization process is the cleaning of surfaces to remove any contaminants and the exposition of hydroxyl groups. As for glasses samples have been washed for 5minutes in acetone in an ultrasonic bath for contaminant removing, then they have been washed three times in distilled water for 5 minutes in ultrasonic bath. Contact angle measurements have been carried out in order to verify OH groups exposition as an increase in surface hydrophilicity. As for titanium samples an acid attack and a thermo-chemical treatment have been realized. Hydroxyls groups have been observed by means of XPS and FTIR analysis. The second step is the introduction of specific functional groups or a surface activation in order to promote and stabilize the bonding with enzyme molecule. In this research work the activation method selected for glasses is silanization [1] with 3-amminopropyltriethoxysilane, which is characterized by amino groups that support biomolecule bonding. Samples have been immersed for 6 hours in a  solution of silane in ethanol, thermally dried in a furnace (1 hour at 100°C) to stabilize bonding between surface hydroxyls and silane molecule, then washed three times in ethanol in ultrasonic bath to remove not-bound molecule and finally thermally dried in furnace 1 hour at 100°C. In order to verify silane grafting on glass surface contact angle measurements and XPS analysis have been carried out. In order to analyze the stability of silane-surface bonding some samples have been washed in TRIS and then observed. As for titanium an activation with Tresyl Chloride has been selected [2,3].  The last step is alkaline phosphatase grafting. Alkaline phosphatase is a glycoprotein containing zinc and magnesium, it is employed in in-vitro tests as a marker for osteoblast differentiation and some studies underline that it promote new bone forming and mineralization [4,5]. Samples have been incubated in a solution of alkaline phosphatase in PBS for 20 hours at 4°C. Reaction has been stopped by a TRIS washing. As for control also samples without silanization (treated only for hydroxyl exposition) have been grafted with ALP. Some samples have been washed in TRIS in ultrasonic bath after ALP anchoring, in order to investigate bond stability. The same grafting process has been applied to both glasses and metal. Samples have been then analyzed in order to examine enzyme grafting, by means of XPS and UV-vis spectroscopy. The first technique studies the chemical elements present on the surface and their state, while the second allows to determine enzyme activity. This last test has been carried out by dipping functionalized samples in a solution containing p-nitrophenilphosphate, which is hydrolyzed by ALP to produce p-nitrophenol which has a yellow coloration, this has been quantified by UV-vis spectroscopy.    Results and Discussion As for hydroxyls exposition tests show that, as expected, surface became hydrophilic. The initial value of contact angle is about 70° and after the different washings it was comprised between 20°  and 30° for all glasses and glass ceramics studied. Titanium samples show OH characteristic peaks both on XPS detailed analysis of oxygen region and on FTIR spectra. As for silanization contact angle measurements exhibit that surface became hydrophobic, values change to 70°-80°. Results show also that the bonding is resistant to TRIS washings, in fact contact angle values remains unvaried after washings (Fig. 1).                 Fig. 1: Contact angle measurement on silanized samples  XPS spectra on samples surfaces show the appearance of nitrogen peak, characteristic of silane amino groups (Table 1). FTIR spectra of tresylated titanium exhibit characteristic peaks for C-F vibrations. As for enzymatic activity evaluations graphs show that the molecule is anchored in active state to the surface of all glasses and glass ceramics tested. After washing the weakly bonded portion of ALP is taken off from sample but a significant part remains on surface (Fig. 2). An aliquot of enzyme could be grafted also onto not-silanized samples (exploiting OH groups), but the bond is weaker, in fact after washings the amount of enzyme that remain on sample’s surface is lower.  Enzymatic activity00,010,020,030,040,050,060,070,080,090,1Sil-glass+ALP Sil-glass+ALP+washabsorbance G1G2G2cer Fig. 2: Enzymatic activity on silanized samples  XPS spectra show an enrichment in carbon and nitrogen  that hide glass constituents on surface of functionalized samples (Table 1).   Table 1: XPS data for samples at different step of functionalization process Sample O Na N Ca C Si Mg Cl S P G1+sil 40.1 0.8 4.1 0.9 32.6 19.5 - - - - Silanization0102030405060708090100Sil Sil+washContact angle [°]G1G2 G1+sil+ALP 23.8 0.8 7.8 - 61.7 - - 4.5 0.3 1.1 G1 37.1 1.9 - 1.8 49.1 10.1 - - - - G1+ALP 23.7 0.8 10.6 - 57.7 - - 6.5 - 0.8 G2 39.4 1.9 1.8 1.7 32.1 16.7 5.7 - - - G2+sil 18.0 2.6 2.6 - 69.9 4.8 1.8 - - - G2+ALP 26.5 0.7 9.2 - 57.3 1.6 - 3.6 - 1.1 G2cer 41.3 1.5 2.0 3.4 31.9 16.4 3.1 - - - G2cer+ALP 31.2 0.7 6.7 2.0 46.3 9.6 - 2.3 - 1.3 G2cer+sil 32.7 2.0 3.5 2.1 46.1 13.0 - - - - G2cer+sil+ALP 25.8 0.2 8.7 0.9 53.3 8.6 - 1.3 1.2 -  Besides a detailed analysis of carbon region exhibit a peak characteristic of C-O and C-N bonds (286 eV) and a peak related to aromatic rings (292-293 eV) that are a mark of ALP presence. It could be noted that on less reactive materials (G1 and G2cer) the bonding with silane and with ALP is stronger and more stable, this happens because in this case bioactivity reactions doesn’t interfere with bonding processes.  Similar results have been obtained for metallic samples. Enzymatic activity tests underline that pure metallic samples didn’t anchor ALP, hydroxylated ones are able to graft an aliquot of biomolecule but a significant amount is anchored only to tresylated samples. As for washing tests results are analogous to glasses ones. Conclusions It is possible to anchor alkaline phosphatase to the surface of glasses and glass-ceramics with different degrees of bioactivity, and to titanium alloy (Ti6Al4V). As for glasses the grafting is realizable both with and without surface silanization, but silane presence on sample’s surface strengthens and stabilizes the bond. Enzyme activity is preserved on all materials after anchoring. In order to evaluate biocompatibility of functionalized materials and investigate cellular response to biological stimuli, in-vitro tests are in progress. Both for cellular test and for future clinical applications of this processes, is in progress a study of the possibility of sterilize functionalized samples without reducing enzyme activity.  References [1]. M. Ma, Y. Zhang, W. Yu, H. Shen, H. Zhang, N. Gu, Colloids and Surface A: Physicochem. Eng. Aspects 212, 2003: 219-226 [2]. D.A.Puleo (1996) Biomaterials 17: 217-222 [3]. T. Hayakawa, M. Yoshinari, K. Nemoto (2003) Wiley Periodicals Inc.684-688 [4] M.C. Groeneveld, V Everts, W. Beertsen, J Dent Res 74(7) (1995) [5] A. Piattelli, A. Scarano, M. Corigliano, M. Piattelli,  Biomaterials 17 (1996)    

English

https://iris.polito.it/retrieve/handle/11583/1652119/48400/S_Ferraris_1652119.pdf

Surface Functionalisation of biomaterials with alkaline phosphatase

Abstract

Similar works

Full text

Available Versions

PORTO Publications Open Repository TOrino

PORTO@iris (Publications Open Repository TOrino - Politecnico di Torino)