www.bioceramics.uni-bremen.deUniversität [email protected]
1
ETH Ceramics20 years5.9.2008
Bioceramics: Multiscale Engineering of Bioceramics: Multiscale Engineering of Advanced Ceramics at the Biology InterfaceAdvanced Ceramics at the Biology Interface
Kurosch RezwanKurosch Rezwan
krezwan@[email protected]
Bioceramics, FB4Bioceramics, FB4UniversitUniversitäät Brement BremenAm Biologischen Garten 2, IW3Am Biologischen Garten 2, IW3D D -- 28359 Bremen28359 BremenTel: +49 421 218 4507Tel: +49 421 218 4507Fax: +49 421 218 7404Fax: +49 421 218 7404
www.bioceramics.uniwww.bioceramics.uni--bremen.debremen.de
www.bioceramics.uni-bremen.deUniversität [email protected]
2
ETH Ceramics20 years5.9.2008
Global ChallengesGlobal Challenges
Filters, Sensors, CatalystsFilters, Sensors, CatalystsClean Air & Clean WaterClean Air & Clean Water
EnvironmentEnvironment
500 µm500 µm
HealthHealthGrowing and Ageing Growing and Ageing PopulationPopulation
Orthopaedic ImplantsOrthopaedic ImplantsBone Replacement MaterialBone Replacement Material
EnergyEnergy
BioreactorsBioreactorsSustainabilitySustainability
150 µm150 µm150 µm
www.bioceramics.uni-bremen.deUniversität [email protected] Ceramics
20 years5.9.2008
LongLong--term implants in Orthopaedics or Dentistryterm implants in Orthopaedics or Dentistry
Degu Dent
Complete Dental Bridge: ZrO2
Pearson Dental Group
Crowns
Hip implants: Al2O3 and ZrO2Ceramtec
www.bioceramics.uni-bremen.deUniversität [email protected] Ceramics
20 years5.9.2008
Use of Zirconia (ZrOUse of Zirconia (ZrO22) for dental bridges) for dental bridges
Wax model of a ceramicdental bridge
800
N80
0 N
800
N
www.bioceramics.uni-bremen.deUniversität [email protected]
5
ETH Ceramics20 years5.9.2008
How to fix implants inside bone?How to fix implants inside bone?
A bioactive coating is necessary to stimulate the bone connection
QUESTION:Which parameters are pivotal for bone connection?
dental implant
artificial hip joint
ww
w.z
fz.d
e
ww
w.m
unni
ch.c
l
HA coatedtitanium implant
ww
w.li
feco
re.c
om
www.bioceramics.uni-bremen.deUniversität [email protected]
6
ETH Ceramics20 years5.9.2008
Investigation of bone cell interactions with materials surfaceInvestigation of bone cell interactions with materials surface
Key Factors
→ geometry, microstructure
→ composition of material
→ roughness
→ porosity
→ biofunctionalisation
→ type of cells
biomoleculescells geometry
material
www.bioceramics.uni-bremen.deUniversität [email protected]
7
ETH Ceramics20 years5.9.2008
Microstructures by Microstructures by ““AirbrushAirbrush”” methodmethod
microchannels generated by M3D
height = ca. 20 µm
Cooperation withFraunhofer Institute forManufacturing Technology and Applied Materials Research(IFAM)
www.bioceramics.uni-bremen.deUniversität [email protected]
8
ETH Ceramics20 years5.9.2008
How do Bone Cells behave in these Microchannels?How do Bone Cells behave in these Microchannels?Tumorousbone cells in calcium phosphate microchannels (SEM)
www.bioceramics.uni-bremen.deUniversität [email protected]
9
ETH Ceramics20 years5.9.2008
Orientation of Bone Cells in MicrochannelsOrientation of Bone Cells in Microchannels
Ceramics without Microstructures
Ceramics with Microstructures
www.bioceramics.uni-bremen.deUniversität [email protected]
10
ETH Ceramics20 years5.9.2008
Orientation of Bone Cells in MicrochannelsOrientation of Bone Cells in Microchannels
• laser ablated HA surface
MG-63→ grew in all microchannels 40-220 µm→ disordered growth in 100 & 220 µm channel → cell alignment due to strut direction
HOB→ no cells in microchannels 40-100 µm→ disordered growth in 220 µm channel → prefered growth on the struts (100 µm)
Focus in microchannel Focus on strut 200 µm
Day 7: HOB40 µm
40 µm
40 µm
100 µm
100 µm
100 µm
220 µm
Focus on strut
Day 7: MG-63
Focus on microchannel 200 µm
40 µm
40 µm
100 µm
100 µm
100 µm
220 µm
40 µm
www.bioceramics.uni-bremen.deUniversität [email protected]
11
ETH Ceramics20 years5.9.2008
FurtherFurther Key Key QuestionsQuestions
• How do healthy and tumorous cells behave in these microchannels?
• Which Biomolecules affect cell growth (A-D) ?
• Which other type of ceramic materials can affect cell proliferation?
sketch of a biofunctionalized µ-structured substrate
A B
C D
www.bioceramics.uni-bremen.deUniversität [email protected]
12
ETH Ceramics20 years5.9.2008
Investigation of bone cell interactions with materials surfaceInvestigation of bone cell interactions with materials surface
Key Factors
→ geometry, microstructure
→ composition of material
→ roughness
→ porosity
→ biofunctionalisation
→ type of cells
biomoleculescells geometry
material
www.bioceramics.uni-bremen.deUniversität [email protected]
13
ETH Ceramics20 years5.9.2008
Hydroxyapatite doped with Silica: Influence on Cell ViabilityHydroxyapatite doped with Silica: Influence on Cell Viability
with SiO2
Ra= 6.1±0.8µm Ra= 4.9±0.6 µm
www.bioceramics.uni-bremen.deUniversität [email protected]
14
ETH Ceramics20 years5.9.2008
Cell ProliferationCell Proliferation
After 7 days we obtain the same cell density.
www.bioceramics.uni-bremen.deUniversität [email protected]
15
ETH Ceramics20 years5.9.2008
BUT: Different expression of collagen type IBUT: Different expression of collagen type I
3-st
aini
ngco
llage
n I
HA doped with SiO2 increases cell expression of proteins that are relevant for bone formation!
[S. Blindow,K. Rezwan, Biomaterialssubmitted]
www.bioceramics.uni-bremen.deUniversität [email protected]
16
ETH Ceramics20 years5.9.2008
ButBut: : HowHow to to healheal bonebone defectsdefects??
www.bioceramics.uni-bremen.deUniversität [email protected]
17
ETH Ceramics20 years5.9.2008
CompositionComposition and and StructureStructure of Boneof Bone
Composition:Bone apatite (~ 70 wt.%) + Collagen (~ 30 wt.%)
CO32-Hydroxyapatite
Macroscopicbone
Osteons(d ~ 100 µm)
Collagen fiber(d ~ 5 µm)
consisting of Collagen fibrils
Collagen fibril (d ~ 500 nm)consisting of collagen molecules
with embedded HAp-crystals(blue, d ~ 20 nm)
Collagen triple helix(d ~ 1.5 nm)
Structure(Compact bone)
1 cm 1 mm 1 µm 100 nm 1 nm
www.bioceramics.uni-bremen.deUniversität [email protected] Ceramics
20 years5.9.2008
What happens without Collagen?What happens without Collagen?
Mechanical testing of bone without Collagen
[AG Prof. Grathwohl, Universität Bremen]
www.bioceramics.uni-bremen.deUniversität [email protected] Ceramics
20 years5.9.2008
What happens without calcium phosphate?What happens without calcium phosphate?
Mechanical testing of bone without calcium phosphate
[AG Prof. Grathwohl, Universität Bremen]
www.bioceramics.uni-bremen.deUniversität [email protected]
20
ETH Ceramics20 years5.9.2008
Challenges• Open Porosity ingrowth of cells• Bioactivity bone bonding and bone healing • Degradability long-term replacement by bone
Further Requirements• Sufficient mechanical properties• Near-net-shape fabrication• Cost effectiveness
1 cm
Bone replacement material: Adjusting mechanicalBone replacement material: Adjusting mechanicaland functional properties to bone materialand functional properties to bone material
www.bioceramics.uni-bremen.deUniversität [email protected]
21
ETH Ceramics20 years5.9.2008
Adaption of Bone MicrostructureAdaption of Bone Microstructure
Goal: Near-net-shape fabrication of calciumphosphate/collagen composites
Freeze Casting Polymer Replica Method
Cortical BoneDense bone with
small pores (~50 µm)
Cancellous Bone (Spongiosa)Spongy bone with
larger pores (~200-500 µm)
www.bioceramics.uni-bremen.deUniversität [email protected]
22
ETH Ceramics20 years5.9.2008
20 µm
500 µm
20 µm
200 µm
Bone(Spongiosa)
Porous Components of Calcium phosphate
2 cm 2 cm
Fabrication of bone replacement material:Fabrication of bone replacement material:Polymer Replica Method and SpongiosaPolymer Replica Method and Spongiosa
www.bioceramics.uni-bremen.deUniversität [email protected]
23
ETH Ceramics20 years5.9.2008
HAp-Ceramic(1wt.% SiO2)
200 µm
Microstructure of unsintered ceramic (ABET= 64.4 ± 0.38 m²/g)
Microstructure of sin-tered ceramic (1100°C) (ABET= 2.6 ± 0.08 m²/g)
Microstructure of Bone(Bio-Oss®, ABET= 88.0 ± 0.12 m²/g)
200 µm
200 µm
20 µm
2 cm
FabricationFabrication of Bone of Bone ReplacementReplacement Material:Material:Freeze Freeze CastingCasting and and CorticalCortical bonebone
www.bioceramics.uni-bremen.deUniversität [email protected]
24
ETH Ceramics20 years5.9.2008
[Deville, et al., Acta Mater., 55, 6]
Casting Freezing and crystal growth
Δ T
- H2O
Drying
Δ T
Sintering
Fabrication method: Freeze CastingFabrication method: Freeze Casting
Water as dispersion medium: Layering of particles between growing column- or lamella shaped ice crystals
20 µm
www.bioceramics.uni-bremen.deUniversität [email protected]
25
ETH Ceramics20 years5.9.2008
Adjustment to Bone MorphologyAdjustment to Bone Morphology
Long bone
1. Variation of pore sizes
2. Polymer-Replica-Method
+ Freeze Casting
2 cm2 cm
2 cm
Micro-CT for MicrostructureVisualisation
www.bioceramics.uni-bremen.deUniversität [email protected]
26
ETH Ceramics20 years5.9.2008
VisualisationVisualisation of 3of 3--D D CeramicCeramic StructureStructure
Mic
ro-C
ompu
terto
mog
raph
y
Scanning Electron Microscopy
www.bioceramics.uni-bremen.deUniversität [email protected]
27
ETH Ceramics20 years5.9.2008
1 Freeze Casting
2 Polymer-Replica-Method
HAp
1.2 HAp
1.1 HAp + Protein
Functionalisationwith Protein
No Sintering2 cm
2 cm Sintering
Fabrication of Ceramic/Protein NanocompositesFabrication of Ceramic/Protein Nanocomposites
www.bioceramics.uni-bremen.deUniversität [email protected]
28
ETH Ceramics20 years5.9.2008
Protein Interaction with Calcium PhosphateProtein Interaction with Calcium Phosphate
Charge distribution of the proteins and particles at adsorption pH and the preferred adsorption directions.
www.bioceramics.uni-bremen.deUniversität [email protected]
29
ETH Ceramics20 years5.9.2008
Mechanical properties of Bone vs. available BiomaterialsMechanical properties of Bone vs. available Biomaterials
[Rezwan et al. Biomaterials. 2006]
0,0001
0,001
0,01
0,1
1
10
100
1000
0,01 0,1 1 10 100 1000 10000Compressive Strength [MPa]
Ela
stic
Mod
ulus
[GP
a]
DenseBiodegradable Polymers
Cortical Bone
SpongiosaBone
Porous Biodegradable Polymers
Porous Biodegradable Composites
Porous Bioactive Ceramics
DenseBioactive Ceramics
www.bioceramics.uni-bremen.deUniversität [email protected]
30
ETH Ceramics20 years5.9.2008
Global Global ChallengesChallenges
Filters, Sensors, Filters, Sensors, CatalystsCatalystsClean Air & Clean WaterClean Air & Clean Water
EnvironmentEnvironment
500 µm500 µm
HealthHealthGrowingGrowing and and AgeingAgeingPopulationPopulation
Orthopaedic ImplantsOrthopaedic ImplantsBone Bone ReplacementReplacement MaterialMaterial
EnergyEnergy
BioreactorsBioreactorsSustainabilitySustainability
150 µm150 µm150 µm
www.bioceramics.uni-bremen.deUniversität [email protected]
31
ETH Ceramics20 years5.9.2008
Biological Contamination of surfacesBiological Contamination of surfaces
Water pipe
Biofilm on indwelling medical device
20 µm 10 µm
Biofilm on a chip
Effects• Material break down• Growth of harmful microorganisms (e. g. Bacteria)
Technical Problems
- Water transport systems- Food Industry- Pharmaceutical / Medical Industry- Shipping
www.bioceramics.uni-bremen.deUniversität [email protected]
32
ETH Ceramics20 years5.9.2008
high durabilityself cleaningantibacterialnon polluting
Strategy for Strategy for selfcleaningselfcleaning surfacessurfaces
Ceramics- Hardness (α-alumina)- Chemical Stability
Natural Biomolecule
- Specific Enzyme withantibacteriel Activity
200 nm
α-Alumina Powder
Lysozyme
www.bioceramics.uni-bremen.deUniversität [email protected]
33
ETH Ceramics20 years5.9.2008
Mikrostructuring with α-Aluminiumoxide = abrasion consistency Biofunctionalisation with Lysozyme = antibacterial surface
Approach: Microstructured surface and BiofunctionalisationApproach: Microstructured surface and Biofunctionalisation
α-alumina surface
α-aluminamicrostructures
Active agent A
Active agent B
SEM images of α-Al2O3 sintered M3D-microstructures
www.bioceramics.uni-bremen.deUniversität [email protected]
34
ETH Ceramics20 years5.9.2008
αα--AlAl22OO33 Microstructure: Test Abrasion Consistency Microstructure: Test Abrasion Consistency
200 µm
After
200 µm
100 µm
Before
100 µm
SEM images of α-Al2O3 sintered microstructures
100 µm
100 µm
Sintered 1000°C
Sintered 1500°C
www.bioceramics.uni-bremen.deUniversität [email protected]
35
ETH Ceramics20 years5.9.2008
M. luteus grown on µ-structured α-Al2O3 surface
Dynamic conditions, after 40 hours
100 µm20 µm
Growth of Growth of BacteriaBacteria WITHOUT WITHOUT antibacterialantibacterial EnzymeEnzyme
Fluorescence microscopy images of bacteria biofilm grown on µ-structured alumina surface, Dead/Live Test
Light microscopy images of sintered (1500°C) α-aluminamicrostructures
50 µm
α-Al2O3 µ-structures on α-Al2O3 surface
--Formation of a dense Formation of a dense biofilm of living Bacteriabiofilm of living Bacteria
Bacteria stream: 500 µl/min
Alive Dead
www.bioceramics.uni-bremen.deUniversität [email protected]
36
ETH Ceramics20 years5.9.2008
Bacteria stream: 500 µl/min
50 µm
Fluorescence microscope images of dead bacteria on µ-structured alumina surface with lysozyme, Dead/Alive Test
Dynamic conditions, after 40 hours
20 µm
Dead bacteria Dye
Dead bacteria
20 µm
Dye
Aliv
eD
ead
Microstructures protect Lysozyme from Microstructures protect Lysozyme from abrasive components and sustain abrasive components and sustain
antibacterial Activity!antibacterial Activity!
WITH WITH antibacterialantibacterial Enzyme: NO growth of Enzyme: NO growth of bacteriabacteria
www.bioceramics.uni-bremen.deUniversität [email protected]
37
ETH Ceramics20 years5.9.2008
PorousPorous BacteriaBacteria filtersfilters withwith large large surfacesurface and high and high PermeabilityPermeability
AntibacterialAntibacterial
EnzymeEnzyme Oxi
de S
urfa
ceO
xide
Sur
faceShort
PeptideLinker
10 µm
nm µm cm
1 cm
Length Scale
200 µm
Scheme of the Molecular Surface Design
AntibacterialAntibacterial
EnzymeEnzyme Oxi
de S
urfa
ceO
xide
Sur
faceShort
PeptideLinker
AntibacterialAntibacterial
EnzymeEnzyme
AntibacterialAntibacterial
EnzymeEnzyme Oxi
de S
urfa
ceO
xide
Sur
faceShort
PeptideLinker
10 µm10 µm10 µm
nm µm cm
1 cm1 cm
Length Scale
200 µm200 µm
Scheme of the Molecular Surface Design
www.bioceramics.uni-bremen.deUniversität [email protected]
38
ETH Ceramics20 years5.9.2008
Multiscale Design of BioceramicsMultiscale Design of Bioceramics
Materials S
cienceM
aterials Science Li
fe S
cien
ces
Life
Sci
ence
s
Bridging the Gap between Materials Science and Biology:Fabrication and Multiscale Interface Engineering of Bioceramics
Colloidal Processing/Sol Gel Technology/
Fabrication of Advanced Ceramics
Biofunctionalisation/ Protein Immobilisation
Investigation ofCell & Bacteria
Responses
Complex Shaping/ Microstructuring/
Solid/Porous Ceramic Components
200 nm
Colloidal Processing/Sol Gel Technology/
Fabrication of Advanced Ceramics
Biofunctionalisation/ Protein Immobilisation
Investigation ofCell & Bacteria
Responses
Complex Shaping/ Microstructuring/
Solid/Porous Ceramic Components
200 nm200 nm
Materials S
cienceM
aterials Science Li
fe S
cien
ces
Life
Sci
ence
s
Bridging the Gap between Materials Science and Biology:Fabrication and Multiscale Interface Engineering of Bioceramics
Colloidal Processing/Sol Gel Technology/
Fabrication of Advanced Ceramics
Biofunctionalisation/ Protein Immobilisation
Investigation ofCell & Bacteria
Responses
Complex Shaping/ Microstructuring/
Solid/Porous Ceramic Components
200 nm
Colloidal Processing/Sol Gel Technology/
Fabrication of Advanced Ceramics
Biofunctionalisation/ Protein Immobilisation
Investigation ofCell & Bacteria
Responses
Complex Shaping/ Microstructuring/
Solid/Porous Ceramic Components
200 nm200 nm
Bioceramics = Ceramics at the Biology InterfaceBioceramics = Ceramics at the Biology Interface
www.bioceramics.uni-bremen.deUniversität [email protected]
39
ETH Ceramics20 years5.9.2008
The Bioceramics GroupThe Bioceramics Group
www.bioceramics.uni-bremen.deUniversität [email protected]
40
ETH Ceramics20 years5.9.2008
Collaborations and FundingCollaborations and FundingUniversity of Bremen
Prof. Grathwohl, CeramicsProf. Blohm, Biotechnology and Molecular GeneticsProf. Thöming, Environmental SciencesProf. Frauenheim, Bremer Centrum for Computational Materials ScienceProf. Lang, Institute for Microsensors, -actuators and -systems
Jacobs University, BremenProf. M. Zacharias, Bioinformatics and Computational BiologyProf. M. Fernandez-Lahore, Biochemical Engineering
Fraunhofer Institut für Fertigungstechnik und Materialforschung, BremenM. Maiwald, Dr. Zöllmer, Dr. Grunwald, Dr. Rischka, Prof. M. Busse
Max Planck Institute for Polymer Research, MainzDr. N. van der Vegt, Computational Chemistry
Imperial College London, UKProf. Dr. A. R. Boccaccini, Materials Department
Funding• European Research Council (Young Investigator Award 2008)• Deutsche Forschungsgemeinschaft (DFG)• Bundesministerium für Bildung und Forschung (BMBF)• Volkswagen Stiftung• Bundesministerium für Wirtschaft und Technologie (BMWi)• Investitionssonderprogramm, Bundesland Bremen