A biomaterial is any substance that has been engineered to interact
with biological systems for a medical purpose - either a therapeutic
(treat, augment, repair or replace a tissue function of the body) or a
diagnostic one. As a science, biomaterials is about fifty years old.
The study of biomaterials is called biomaterials science or
biomaterials engineering. It has experienced steady and strong growth
over its history, with many companies investing large amounts of money
into the development of new products.
Biomaterials science encompasses
elements of medicine, biology, chemistry, tissue engineering and
Note that a biomaterial is different from a biological material, such
as bone, that is produced by a biological system. Additionally, care
should be exercised in defining a biomaterial as biocompatible, since
it is application-specific. A biomaterial that is biocompatible or
suitable for one application may not be biocompatible in another.
Material exploited in contact with living tissues, organisms, or
4 Structural hierarchy
5.1 Heart valves
5.2 Skin repair
8 See also
11 External links
Biomaterials can be derived either from nature or synthesized in the
laboratory using a variety of chemical approaches utilizing metallic
components, polymers, ceramics or composite materials. They are often
used and/or adapted for a medical application, and thus comprises
whole or part of a living structure or biomedical device which
performs, augments, or replaces a natural function. Such functions may
be relatively passive, like being used for a heart valve, or may be
bioactive with a more interactive functionality such as
hydroxy-apatite coated hip implants.
Biomaterials are also used every
day in dental applications, surgery, and drug delivery. For example, a
construct with impregnated pharmaceutical products can be placed into
the body, which permits the prolonged release of a drug over an
extended period of time. A biomaterial may also be an autograft,
allograft or xenograft used as a transplant material.
Main article: Biomineralization
Biomineralization is the process by which living organisms produce
minerals, often to harden or stiffen existing tissues. Such tissues
are called mineralized tissues. It is an extremely widespread
phenomenon; all six taxonomic kingdoms contain members that are able
to form minerals, and over 60 different minerals have been identified
in organisms. Examples include silicates in algae and
diatoms, carbonates in invertebrates, and calcium phosphates and
carbonates in vertebrates. These minerals often form structural
features such as sea shells and the bone in mammals and birds.
Organisms have been producing mineralised skeletons for the past 550
million years. Other examples include copper, iron and gold deposits
involving bacteria. Biologically-formed minerals often have special
uses such as magnetic sensors in magnetotactic bacteria (Fe3O4),
gravity sensing devices (CaCO3, CaSO4, BaSO4) and iron storage and
mobilization (Fe2O3•H2O in the protein ferritin).
Self-assembly is the most common term in use in the modern scientific
community to describe the spontaneous aggregation of particles (atoms,
molecules, colloids, micelles, etc.) without the influence of any
external forces. Large groups of such particles are known to assemble
themselves into thermodynamically stable, structurally well-defined
arrays, quite reminiscent of one of the 7 crystal systems found in
metallurgy and mineralogy (e.g. face-centered cubic, body-centered
cubic, etc.). The fundamental difference in equilibrium structure is
in the spatial scale of the unit cell (or lattice parameter) in each
Molecular self-assembly is found widely in biological systems and
provides the basis of a wide variety of complex biological structures.
This includes an emerging class of mechanically superior biomaterials
based on microstructural features and designs found in nature. Thus,
self-assembly is also emerging as a new strategy in chemical synthesis
and nanotechnology. Molecular crystals, liquid crystals, colloids,
micelles, emulsions, phase-separated polymers, thin films and
self-assembled monolayers all represent examples of the types of
highly ordered structures which are obtained using these techniques.
The distinguishing feature of these methods is
Nearly all materials could be seen as hierarchically structured,
especially since the changes in spatial scale bring about different
mechanisms of deformation and damage. However, in biological materials
this hierarchical organization is inherent to the microstructure. One
of the first examples of this, in the history of structural biology,
is the early X-ray scattering work on the hierarchical structure of
hair and wool by Astbury and Woods. In bone, for example, collagen
is the building block of the organic matrix — a triple helix with
diameter of 1.5 nm. These tropocollagen molecules are
intercalated with the mineral phase (hydroxyapatite, a calcium
phosphate) forming fibrils that curl into helicoids of alternating
directions. These "osteons" are the basic building blocks of bones,
with the volume fraction distribution between organic and mineral
phase being about 60/40.
In another level of complexity, the hydroxyapatite crystals are
mineral platelets that have a diameter of approximately
70–100 nm and thickness of 1 nm. They originally nucleate
at the gaps between collagen fibrils.
Similarly, the hierarchy of abalone shell begins at the nanolevel,
with an organic layer having a thickness of 20–30 nm. This
layer proceeds with single crystals of aragonite (a polymorph of
CaCO3) consisting of "bricks" with dimensions of 0.5 and finishing
with layers approximately 0.3 mm (mesostructure).
Crabs are arthropods whose carapace is made of a mineralized hard
component (which exhibits brittle fracture) and a softer organic
component composed primarily of chitin. The brittle component is
arranged in a helical pattern. Each of these mineral ‘rods’ (1 μm
diameter) contains chitin–protein fibrils with approximately
60 nm diameter. These fibrils are made of 3 nm diameter
canals which link the interior and exterior of the shell.
Biomaterials are used in:
Intraocular lenses (IOLs) for eye surgery
Artificial ligaments and tendons
Dental implants for tooth fixation
Blood vessel prostheses
Skin repair devices (artificial tissue)
Drug delivery mechanisms
Surgical sutures, clips, and staples for wound closure
Pins and screws for fracture stabilisation
Biomaterials must be compatible with the body, and there are often
issues of biocompatibility which must be resolved before a product can
be placed on the market and used in a clinical setting. Because of
this, biomaterials are usually subjected to the same requirements as
those undergone by new drug therapies.
All manufacturing companies are also required to ensure traceability
of all of their products so that if a defective product is discovered,
others in the same batch may be traced.
In the United States, 45% of the 250,000 valve replacement procedures
performed annually involve a mechanical valve implant. The most widely
used valve is a bileaflet disc heart valve, or St. Jude valve. The
mechanics involve two semicircular discs moving back and forth, with
both allowing the flow of blood as well as the ability to form a seal
against backflow. The valve is coated with pyrolytic carbon, and
secured to the surrounding tissue with a mesh of woven fabric called
Dacron (du Pont's trade name for polyethylene terephthalate). The mesh
allows for the body's tissue to grow while incorporating the
Main article: Tissue engineering
Most of the time, ‘artificial’ tissue is grown from the
patient’s own cells. However, when the damage is so extreme that it
is impossible to use the patient's own cells, artificial tissue cells
are grown. The difficulty is in finding a scaffold that the cells can
grow and organize on. The characteristics of the scaffold must be that
it is biocompatible, cells can adhere to the scaffold, mechanically
strong and biodegradable. One successful scaffold is a copolymer of
lactic acid and glycolic acid.
Biocompatibility is related to the behavior of biomaterials in various
environments under various chemical and physical conditions. The term
may refer to specific properties of a material without specifying
where or how the material is to be used. For example, a material may
elicit little or no immune response in a given organism, and may or
may not able to integrate with a particular cell type or tissue. The
ambiguity of the term reflects the ongoing development of insights
into how biomaterials interact with the human body and eventually how
those interactions determine the clinical success of a medical device
(such as pacemaker or hip replacement). Modern medical devices and
prostheses are often made of more than one material—so it might not
always be sufficient to talk about the biocompatibility of a specific
Main article: Biopolymer
Biopolymers are polymers produced by living organisms.
starch, proteins and peptides, and
RNA are all examples of
biopolymers, in which the monomeric units, respectively, are sugars,
amino acids, and nucleotides.
Cellulose is both the most common
biopolymer and the most common organic compound on Earth. About 33% of
all plant matter is cellulose.
Surface modification of biomaterials with proteins
Synthetic biodegradable polymer
List of biomaterials
^ The notion of exploitation includes utility for applications and for
fundamental research to understand reciprocal perturbations as
^ The definition “non-viable material used in a medical device,
intended to interact with biological systems” recommended in ref.
cannot be extended to the environmental field where people mean
“material of natural origin”.
^ This general term should not be confused with the terms biopolymer
or biomacromolecule. The use of “polymeric biomaterial” is
recommended when one deals with polymer or polymer device of
therapeutic or biological interest.
^ Schmalz, G.; Arenholdt-Bindslev, D. (2008). "Chapter 1: Basic
Biocompatibility of Dental Materials. Berlin:
Springer-Verlag. pp. 1–12. ISBN 9783540777823. Archived
from the original on 9 December 2017. Retrieved 29 February
^ a b c d Vert, M.; Doi, Y.; Hellwich, K. H.; Hess, M.; Hodge, P.;
Kubisa, P.; Rinaudo, M.; Schué, F. O. (2012). "Terminology for
biorelated polymers and applications (IUPAC Recommendations 2012)".
Pure and Applied Chemistry. 84 (2).
^ Williams, D. F., ed. (2004). Definitions in Biomaterials,
Proceedings of a Consensus Conference of the European Society for
Biomaterials. Amsterdam: Elsevier.
^ Harris, Ph.D., Edward D. (1 January 2014). Minerals in Food
Nutrition, Metabolism, Bioactivity (1st ed.). Lancaster, PA: DEStech
Publications, Inc. p. 378. ISBN 978-1-932078-97-8. Retrieved
30 January 2015.
^ Astrid Sigel; Helmut Sigel; Roland K.O. Sigel, eds. (2008).
Biomineralization: From Nature to Application. Metal Ions in Life
Sciences. 4. Wiley. ISBN 978-0-470-03525-2.
^ Weiner, Stephen; Lowenstam, Heinz A. (1989). On biomineralization.
Oxford [Oxfordshire]: Oxford University Press.
^ Jean-Pierre Cuif; Yannicke Dauphin; James E. Sorauf (2011).
Biominerals and fossils through time. Cambridge.
^ Whitesides, G.; Mathias, J.; Seto, C. (1991). "Molecular
self-assembly and nanochemistry: A chemical strategy for the synthesis
of nanostructures". Science. 254 (5036): 1312–9.
^ Dabbs, D. M.; Aksay, I. A. (2000). "Self-Assembledceramicsproduced
Bycomplex-Fluidtemplation". Annual Review of Physical Chemistry. 51:
doi:10.1146/annurev.physchem.51.1.601. PMID 11031294.
^ Ariga, K.; Hill, J. P.; Lee, M. V.; Vinu, A.; Charvet, R.; Acharya,
S. (2008). "Challenges and breakthroughs in recent research on
self-assembly". Science and Technology of Advanced Materials. 9 (1):
014109. Bibcode:2008STAdM...9a4109A. doi:10.1088/1468-6996/9/1/014109.
PMC 5099804 . PMID 27877935.
^ Stroud, R. M. (2006). "Present at the flood: How structural biology
came about, by Richard E. Dickerson".
Protein Science. 16: 135–136.
^ Ibrahim, H.; Esfahani, S. N.; Poorganji, B.; Dean, D.; Elahinia, M.
(January 2017). "Resorbable bone fixation alloys, forming, and
post-fabrication treatments". Materials Science and Engineering: C. 70
(1): 870. doi:10.1016/j.msec.2016.09.069.
^ Pillai, C. K. S.; Sharma, C. P. (2010). "Review Paper: Absorbable
Polymeric Surgical Sutures: Chemistry, Production, Properties,
Biodegradability, and Performance". Journal of Biomaterials
Applications. 25 (4): 291–366. doi:10.1177/0885328210384890.
^ Pillai CK, Sharma CP (Nov 2010). "Review paper: absorbable polymeric
surgical sutures: chemistry, production, properties, biodegradability,
and performance". J Biomater Appl. 25 (4): 291–366.
doi:10.1177/0885328210384890. PMID 20971780.
^ Waris, E; Ashammakhi, N; Kaarela, O; Raatikainen, T; Vasenius, J
(December 2004). "Use of bioabsorbable osteofixation devices in the
hand". Journal of hand surgery (Edinburgh, Scotland). 29 (6): 590–8.
doi:10.1016/j.jhsb.2004.02.005. PMID 15542222.
^ Deasis, F. J.; Lapin, B; Gitelis, M. E.; Ujiki, M. B. (2015).
"Current state of laparoscopic parastomal hernia repair: A
meta-analysis". World Journal of Gastroenterology. 21 (28): 8670–7.
doi:10.3748/wjg.v21.i28.8670. PMC 4524825 .
^ Banyard, D. A.; Bourgeois, J. M.; Widgerow, A. D.; Evans, G. R.
(2015). "Regenerative biomaterials: A review". Plastic and
Reconstructive Surgery. 135 (6): 1740–8.
doi:10.1097/PRS.0000000000001272. PMID 26017603.
^ Meyers, M. A.; Chen, P. Y.; Lin, A. Y. M.; Seki, Y. (2008).
"Biological materials: Structure and mechanical properties". Progress
in Materials Science. 53: 1–206.
^ Espinosa, H. D.; Rim, J. E.; Barthelat, F.; Buehler, M. J. (2009).
"Merger of structure and material in nacre and bone – Perspectives
on de novo biomimetic materials". Progress in Materials Science. 54
(8): 1059–1100. doi:10.1016/j.pmatsci.2009.05.001.
^ a b Brown, Theodore L.; LeMay, H. Eugene; Bursten, Bruce E. (2000).
Chemistry The Central Science. Prentice-Hall, Inc. pp. 451–452.
^ Kammula, R. G. and Morris, G. M. (2001) "Considerations for the
Biocompatibility Evaluation of Medical Devices" Archived 2011-07-07 at
the Wayback Machine., Medical Device & Diagnostic Industry
^ Buehler, M. J.; Yung, Y. C. (2009). "Deformation and failure of
protein materials in physiologically extreme conditions and disease".
Nature Materials. 8 (3): 175–88. Bibcode:2009NatMa...8..175B.
doi:10.1038/nmat2387. PMID 19229265.
^ Stupp, S. I.; Braun, P. V. (1997). "Molecular manipulation of
microstructures: Biomaterials, ceramics, and semiconductors". Science.
277 (5330): 1242–8. doi:10.1126/science.277.5330.1242.
^ Klemm, D; Heublein, B; Fink, H. P.; Bohn, A (2005). "Cellulose:
Fascinating biopolymer and sustainable raw material". Angewandte
Chemie International Edition. 44 (22): 3358–93.
doi:10.1002/anie.200460587. PMID 15861454.
CREB – Biomedical Engineering Research Centre
Biomaterials at the Max Planck Institute of
Interfaces in Potsdam-Golm, Germany
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