37-4
26 h Eu opean Con e ence on Bioma e ials, Li e pool, 31s Augus – 3 d Sep embe 2014
Su ace unc ionalisa ion o sol-gel-based bioac i e glass sca olds o d ug deli e y
A. Philippa 1*, A. M. Bel án2, L. Pon i oli3, C.Vi ale-B o a one3, E. Spiecke 2 and A. R. Boccaccini1
1Ins i u e o Bioma e ials, Uni e si y E langen-Nü nbe g, Ge many, anahi.philippa [email p o ec ed]e
2Cen e o Nanoanalysis and Elec on Mic oscopy (CENEM), Uni e si y E langen-Nü nbe g, Ge many
3Ins i u e o Ma e ials Physics and Enginee ing, Applied Science and Technology Dep ., Poli ecnico di To ino, I aly
INTRODUCTION
Bioac i e glasses a e widely used in bone issue
enginee ing (BTE) since hey can de elop s ong bonds
wi h bone h ough he o ma ion o a hyd oxyapa i e
(HA) laye 1. Wi hin hese ma e ials, sol-gel-based
bioac i e glasses (SGBGs) a e a ac i e due o hei
enhanced bioac i i y and eso babili y and hei
capaci y o being unc ionalised wi h a la ge a ie y o
moie ies2-3.
Su ace unc ionalisa ion is an in e es ing app oach o
load d ugs in o he ma e ial and allow hei elease in a
con olled manne 3.
The aim o his s udy is he de elopmen o new
SGBGs o 3D po ous sca olds and unc ionalisa ion o
hei su ace by wo di e en me hods4-5 in o de o
enhance he d ug deli e y capabili y.
EXPERIMENTAL METHODS
Bioac i e glass sca olds wi h composi ion (in mol%)
60SiO2 30CaO 5Na2O 5P2O5 we e p epa ed by he sol
gel me hod and he oam eplica echnique. Sca olds
we e cha ac e ised by scanning elec on mic oscopy
(SEM) and µ-CT, in o de o e alua e he
mac os uc u e and po osi y and by ansmission
elec on mic oscopy (TEM) and N2 adso p ion
po osime y using he B unaue -Emme -Telle (BET)
app oach o mesopo osi y cha ac e isa ion. Bioac i i y
was e ealed by Fou ie ans o m in a ed
spec oscopy (FTIR) cha ac e isa ion o he sca olds
a e SFB imme sion.
A e hea ea men a 700°C, he sca olds su ace was
unc ionalised by pos -condensa ion o aminosilane,
ollowing he eac ion shown below:
A second s ep was conside ed o a oid s e ic
in e e ence by adding a space and allowing an op imal
loading o he model d ug.
Bo h sys ems we e loaded wi h a model d ug, and he
d ug elease capabili ies we e s udied in wo di e en
media by UV-Vis spec oscopy.
RESULTS AND DISCUSSION
Sca olds exhibi ed he equi ed mac opo e size
(~500μm) as well as high and in e connec ed po osi y,
o up o 90% as shown in Fig.1 (a-c). TEM (Fig.1 d)
e ealed he mesopo osi y, con i med by BET analysis
(po e size: ~4nm; SBET=150m2/g). Bo h po osi ies a e
ea u es equi ed by sca olds o BTE and d ug
deli e y applica ions1-2.
Figu e 1. Images o sca old a,b)SEM mic og aphs,
c) µ-CT econs uc ion, d)TEM mic og aph
Amino- unc ionalisa ion o he su ace was con i med
by ze a po en ial measu emen s, ninhyd ine es as well
as by elemen mapping in SEM.
The di e en d ug elease p o iles showed ha by
su ace unc ionalisa ion i was possible o achie e a
educed ini ial bu s elease o he d ug in he es ed
media and a long- e m sus ained elease.
CONCLUSION
Acco ding o SEM and µ-CT econs uc ions, 3D
po ous sca olds we e success ully p epa ed, exhibi ing
mac o- and mesopo osi y. Fu he mo e, amino-
unc ionalised su ace allowed he sys em o exhibi a
sus ain elease o he model d ug compa ed o non-
unc ionalised sca olds.
REFERENCES
1. Ge ha d L.C. e al.,Ma e ials 3:3867-3910, 2010
2. Jones J. R. e al., Bioma e ials 27:964-973, 2006
3. Valle Regi M.e al., Phil. T ans. R. Soc. A
370:1400-1421, 2012
4. Balas F. e al., J. Am. Chem. Soc. 128:8116-8117,
2006
5. Schneide M. e al., Langmui 29:6983-88, 2013
ACKNOWLEDGMENTS
The au ho s would like o hank ITN FP-7 p ojec
“GlaCERCo” o p o iding inancial suppo ; P. Rosne
o he help p o ided in TEM; P o . E. Ve né and D .
Sonia Fio illi o he assis ance in he ma e ial
cha ac e isa ion; D . A. Inaya o BET analysis.