Faculty

Christine Ortiz

 

Disciplines

Research

The focus of the Ortiz research program is on structural or load-bearing biological materials, in particular musculoskeletal (internal to the body) and exoskeletal (extermal to the body) tissues. Such systems have developed hierarchical and heterogeneous composite structures over millions of years of evolution in order to sustain the mechanical loads experienced in their specific environment. For this reason, they have enjoyed a long and distinguished history in the literature of more than a century with an emphasis on macroscopic, continuum-level biomechanics. The Ortiz research group studies these fascinating materials using expertise in the field of "nanomechanics," including the measurement and prediction of extremely small forces and displacements, the quantification of nanoscale spatially-varying mechanical properties, the identification of local constitutive laws, the formulation of molecular-level structure-property relationships, and the investigation of new mechanical phenomena existing at small length scales. Novel experimental and theoretical methods are employed, involving increasing levels of complexity from individual molecules to biomimetic molecular assemblies to the matrix associated with single cells and, lastly, to the nanoscale properties of the intact tissue. The result, and ultimate objective of the Ortiz research program, is a fundamental, mechanistic-based understanding of tissue function, quality, and pathology. The scientific foundation being formed has relevance to both the medical and engineering fields. Nanotechnological methods applied to the field of musculoskeletal tissues and tissue engineering hold great promise for significant and rapid advancements towards tissue repair and/or replacement, improved treatments, and possibly even a cure for people afflicted with diseases such as osteoarthritis. In addition, the discovery of new nanoscale design principles and energy-dissipating mechanisms will enable the production of improved and increasingly advanced biologically-inspired structural engineering materials and protective defense technologies that exhibit "mechanical property amplification"—that is, dramatic improvements in mechanical properties (e.g., increases in strength and toughness) for a material relative to its constituents. Their work in musculoskeletal tissues focuses on articular cartilage, bone, and intervertebral disc. Their work in exoskeletal structures involves natural flexible armor, transparent armor, armor for biochemical toxin resistance, kinetic attacks, thermal regulation, and blast dissipation. Model systems include armored fish, deep sea hydrothermal vent and antarctic molluscs, molluscs and echinoderms with articulating plate armor (e.g. chitons, C. atratus), the transparent exoskeletons of certain crustaceans and pteropods, etc.

Selected Publications

Bruet, B. J. F.; Song, J.; Boyce, M. C.; Ortiz, C., “Materials Design Principles of Ancient Fish Armor,” Nature Materials, 7(9), 748–756, 2008 (Cover of Issue)

Ortiz, C. and M. C. Boyce, “Bioinspired Structural Materials,” Science 319(5866), 1053–1054, 2008.

Tai, K.; Dao, M.; Suresh, S.; Palazoglu, A.; Ortiz, C., "Nanoscale heterogeneity promotes energy dissipation in bone," Nature Materials 2007, 6, (6) 454–46.

Ng, L.; Hung, H.-H.; Sprunt, A.; Chubinskaya, S.; Ortiz, C.; Grodzinsky, A., " Nanomechanical properties of individual chondrocytes and their developing growth factor-stimulated pericellular matrix," Journal of Biomechanics 2007, 40, (5), 1011–1023.

Tai, K.; Ulm, F. J.; Ortiz, C., "Nanogranular origins of the strength of bone," Nano Letters 2006, 6, (11), 2520–2525.

Dean, D.; Han, L.; Grodzinsky, A. J.; Ortiz, C., "Compressive nanomechanics of opposing aggrecan macromolecules," Journal of Biomechanics 2006, 39, (14), 2555–256.

Related News

MIT team examines effect of exercise on arthritis
MIT engineers find that in the earliest stages of arthritis, high-impact exercise may worsen cartilage damage.
April 26, 2013
Prof. Ortiz named dean for graduate education
Prof. Christine Ortiz will be the new dean for graduate education, effective Aug. 1.
June 29, 2010
DMSE faculty participate in Manufacturing Round Table discussion
Prof. Gerd Ceder and Prof. Christine Ortiz were participants in an MIT roundtable discussion titled, The Future of Manufacturing — Advanced Technologies.
April 1, 2010
Christine Ortiz promoted to full professor
Congratulations to Christine Ortiz who will be a full professor, effective July 1, 2010.
March 26, 2010
Prof. Christine Ortiz interviewed by Spectrum
See the Spring 2010 Spectrum to learn more about work performed by Prof.
March 24, 2010
DMSE professors publish research on snail shells
New insights about a tiny snail that lives on the ocean floor could help scientists design better armor for soldiers and vehicles, according to Professors Christine Ortiz and Subra Suresh.
January 19, 2010