Department of Materials Science and Engineering

Dr. Estroff’s early training was in the field of synthetic organic chemistry at Swarthmore College in Pennsylvania. She graduated from Swarthmore in 1997 with a B.A., with Honors, in chemistry and a minor in anthropology. Before beginning her graduate studies, Dr. Estroff spent a year at the Weizmann Institute of Science in Rehovot, Israel as a visiting researcher in the labs of Profs Lia Addadi and Steve Weiner. During this time, she was introduced to the field of biomineralization and studied chemical approaches to archeological problems. Dr. Estroff then spent five years in Prof. Andrew D. Hamilton’s laboratory developing bio-inspired synthetic approaches to inorganic and organic materials at Yale University. Based on her Ph.D. work, she received both a graduate fellowship from the Division of Organic Chemistry of the American Chemical Society and a graduate student silver award from the Materials Research Society. After receiving her Ph.D. in 2003, she spent two years as an NIH-funded postdoctoral researcher in Prof. George M. Whiteside's laboratory at Harvard University (2003-2005). During this time, she learned techniques as diverse as protein purification, nanoparticle synthesis, and soft lithography. Dr. Estroff has been a member of the Materials Science and Engineering department at Cornell University since August 2005. In Dec. 2006, she was awarded a J.D. Watson Young Investigator’s award from NYSTAR. She is a member of the Materials Research Society, the American Chemical Society, Phi Beta Kappa, and Sigma Xi.

Dr. Estroff’s research focus is on the bio-inspired synthesis of organic-inorganic composites. Biological organisms create multi-functional and adaptive materials (e.g., bone, teeth, sea shells) from inexpensive, readily available building blocks using mild, energy-efficient, and non-toxic processes. Accordingly, there is tremendous interest in mimicking and controlling biology both to create new synthetic materials and to maintain the health of naturally occurring tissues. The two major themes of Dr. Estroff’s research are: 1) The synthesis of new organic and inorganic materials with altered morphologies and mechanical properties. The design of these materials is based upon biological examples of mineralization. 2) The development of in vitro models to answer questions about the mechanisms of biomineralization. One primary research focus in the laboratory is the use of hydrogels to control the growth of crystals. A hydrogel, like Jell-O®, is a hydrated (usually > 95 w/v% water) organic matrix that does not exhibit flow (e.g., a vial containing a hydrogel can be turned upside down and the material will not flow). Hydrogels are associated with a number of biomineralizing systems, including the mother-of-pearl in mollusk shells and tooth enamel in mammals. An outstanding question is why organisms use hydrogels to control crystal growth. Dr. Estroff has established a research program to begin to address this question.

1. The integration of self-assembled monolayers with natural and synthetic hydrogels to create systems in which both nucleation and crystal growth are controlled. Examples include agarose and silk fibroin gels for controlling the growth of calcite (CaCO3) and agarose gels for growing bone-like carbonated apatite (Ca10(PO4,CO3)6(OH)2) crystals. Recent work in Estroff’s laboratory has revealed that when calcite is grown in an agarose hydrogel, the organic material is occluded inside of the crystal. Currently, they are investigating the mechanical properties of these composites.
2. The use of block copolymers to structure amorphous calcium phosphate and calcium carbonate nanoparticles. Our approach is to combine calcium phosphate minerals with the well-established ability of amphiphilic (hydrophobic/hydrophilic) block copolymers to direct the assembly of inorganic materials into mesostructured hybrids (with e.g., cylindrical, lamellar, or bicontinuous morphologies). We will start from amorphous calcium phosphate particles as a precursor phase, which, after structure formation with the block copolymers, will be crystallized to form robust composites with carbonated apatite nanocrystals as the inorganic component. In the future, these nanostructured composites will be used to form self-hardening composites. (In collaboration with the Wiesner group.)
3. The use of self-assembled monolayers as nucleating surfaces to screen pharmaceuticals and organic pigments for polymorphism.

1. Estroff, L. A.; Hamilton, A. D.* "Effective gelation of water using a series of bis-urea dicarboxylic acids" Angew. Chem. Int. Ed. Engl. 2000, 39, 3447-3450.
2. Estroff, L. A.; Hamilton, A. D.* "At the interface of organic and inorganic chemistry: Bio-inspired synthesis of composite materials" Chem. Mater. 2001, 13, 3227-3235.
3. Estroff, L.A.; Leiserowitz, L.; Addadi, L.; Weiner, S.; and Hamilton, A.D.* “Characterization of an Organic Hydrogel: A Cryo-TEM and X-ray Diffraction Study” Adv. Mater. 2003, 15, 38-42.
4. Estroff, L.A.; Incarvito, C.D.; Hamilton, A.D.* “Design of a Synthetic Foldamer that Modifies the Growth of Calcite Crystals” J. Am. Chem. Soc. 2004, 126, 2-3.
5. Estroff, L.A.; Addadi, L.; Weiner, S.; Hamilton, A.D.* “An Organic Hydrogel for the Growth of Calcium Carbonate” Org. & Biomol. Chem. 2004, 137-141.
6. Estroff, L.A.; Hamilton, A.D.* “Water Gelation by Small Organic Molecules” Chem. Rev., 2004, 104, 1201-1218.
7. Love, J.C.; Estroff, L.A.; Kriebel, J.K.; Nuzzo, R.G.*; Whitesides, G.M.* “Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology” Chem. Rev., 2005, 105, 1103-1170.
8. Li, H and Estroff, L.A.* “Hydrogels Coupled with SAMs: An in Vitro Matrix to Study Calcite Biomineralization.” 2007, Submitted for publication.

Education

• Swarthmore College, Swarthmore, PA Chemistry BA 1997
• Yale University, New Haven, CT Chemistry Ph.D. 2003

Appointments

• Assistant Professor of Mater. Sci. and Engin., Cornell, 8/05-present
• NIH-funded Post-doctoral Researcher, Harvard University, 8/03-7/05
• Visiting Researcher, Weizmann Institute of Science, Rehovot, Israel, 8/97-8/98