General

 
Krause's research interests focus on structure-property relationships of macromolecules (polymers) with an emphasis on their mechanical (rheological) properties and their response to mechanical stimulus. Of great personal interest to Krause are biologically and medically relevant macromolecules and fibers (two related projects are highlighted below). In addition, Krause continues to be fascinated by polyelectrolyte solution dynamics, rheology and structure of colloids, electrostatic self assembly of nanolayers, the mechanical properties of nanocomposites, lubrication and biolubrication, tribology as it relates to lubrication, gels, tissue engineering, and biomaterials. 

Synovial Fluid

Synovial fluid is the fluid that lines our freely moving (synovial) joints, and is vital to joint lubrication. Normal synovial joints exhibit an extremely low coefficient of friction--similar to an ice skate on ice--and their cartilage does not abrade over several decades. This is not the case for arthritic joints. In comparison to healthy synovial fluid, diseased fluid has a reduced viscosity. In OA this reduction in viscosity results from a decline in both the molecular weight and concentration of hyaluronic acid (HA). The polyelectrolyte HA is a glycosaminoglycan and an important component of synovial fluid. Its presence results in highly viscoelastic solutions with excellent lubricating and shock-absorbing properties. To advance our understanding of how HA contributes to the vital mechanical properties of synovial fluid, an experimental model will be refined, characterized, and compared to bovine/equine synovial fluid. The rheological properties of bovine/equine synovial fluid, the synovial fluid model (SFM), and its components will be investigated in the presence and absence of anti-inflammatory drugs.

Biopolymer Nanofibers

Tissue engineering is a promising field which may resolve problems with organ and tissue transplantation (i.e., donor shortage and immune rejection) through fabrication of biological alternatives for harvested organs and tissues. One approach to tissue engineering utilizes a biodegradable scaffold onto which cells are seeded and cultured, and ideally developed into functional tissue. The scaffold acts as an artificial, extracellular matrix (ECM). In natural tissues, the ECM has physical structural features ranging from the nanometer scale to the micrometer scale. When designing a novel tissue engineering scaffold, the cells' native environment should be mimicked as closely as possible (typical collagen fibers of the ECM have diameters in the range of 50 - 500 nm). To mimic natural ECM, we propose to develop an artificial ECM from biopolymer nanofibers. These biopolymer nanofibers will be fabricated via electrostatic spinning (electrospinning). Unlike conventional fiber spinning techniques (e.g., wet spinning, dry spinning, melt spinning, etc.), which produce polymer fibers with diameters down to the micrometer scale, electrospinning  is a process capable of producing submicron size fiber on the order of 100 nm in diameter.

·         Doctoral Students

o   Rebecca R. Klossner, Ph.D. FPS, “Rheological and Tribiological Properties of Complex Biopolymer Solutions,” co-chair with Prof. Saad Khan, degree in progress.

o   Hongyi Liu, Ph.D FPS, “Molecular Dynamics Simulations of Textile Lubricants,” co-chair with Prof. Orlando J. Rojas, degree in progress.

·         Masters Students

o   Shu Zhang, M.S. TC, “Mechanical Properties of Electrospun Fibers,” chair, degree in progress.

 Previous Students:

·         Doctoral Students

o   Jing Liang, Ph.D. FPS, “Investigation of Synthetic and Natural Lubricants,” co-chair with Prof. Alan E. Tonelli, (defended 7/10/08).

·         Masters Students

o   Paul R. Shannon, M.L.S. (Master in Liberal Studies), Interdisciplinary (non-thesis), co-chair, (completed summer 2008).

o   Hailey A. Queen, M.S. TE, “Electrospinning Chitosan Nanofibers for Biomedical Coatings,” chair, (defended 6/8/06).

o   Denice S. Young, M.S. MSE, “Fabrication of Biopolymer Nanofibers of Hyaluronic Acid via Electrospinning,” co-chair with Prof. C. Maurice Balik, (defended 5/8/06).

o   Megan A. Christie, M.S. TE & BME, “Keratinocyte and Hepatocyte Growth Proliferation and Adhesion to Helium and Helium/Oxygen Atmospheric Pressure Plasma Treated Polyethylene Terephthalate,” co-chair with Prof. Mohamed A. Bourham, (defended 11/3/05).

2000 The Pennsylvania State University, Ph.D./Chemistry
Thesis: "Solution Dynamics of Synthetic and Natural Polyelectrolytes" Adviser: Ralph H. Colby (Professor of Polymer Science, Department of Material Science & Engineering)

1993 Massachusetts Institute of Technology, S.B./Chemistry

·     American Chemical Society

·     American Physical Society

·     Society of Rheology

Wendy Krause, daughter of Brandy Krause and the late Phil Krause, grew up in Maine where she attended Mt. Blue High School. She was an active student, participating on both the varsity soccer and alpine ski teams. Wendy entered MIT in the fall of 1989. While majoring in chemistry, she participated in the Undergraduate Research Opportunities Program, conducting research in Prof. W. H. Orme-Johnson's and Prof. H.-C. zur Loye's laboratories. She received the Harold W. Fisher Scholarship (1991-1992) and the Carl P. and Marie G. Dennett Scholarship (1992-1993). Wendy skied for MIT's varsity alpine ski team for four years and played on the soccer team her first year. After graduating from MIT in 1993, Wendy began her graduate studies in the Chemistry Department at Penn State where she received the International Paper Fellowship (1993). In 1996, Prof Ralph H. Colby (Materials Science and Engineering) became her thesis advisor. With Prof. Colby, Wendy investigated the solution dynamics of polyelectrolytes and experimentally modeled synovial fluid. In 1999, she was an American Physical Society Padden Award Finalist. Her research on the rheology of synovial was highlighted in "Polymer Science Seeks Clues to Why HA Becomes no Laughing Matter" by writer/editor Gary W. Cramer (Penn State MATSE 2000, IV, 3 - 4) and in "How Aspirin Works" by David Pacchioli (Research/Penn State1999, 20(1), 12 ). After receiving her Ph.D. in 2000, Wendy became a Research Scientist at a small technology development company in College Station, Texas. While there, Wendy secured over $450,000 in extramural funding through the federal government's SBIR program. In 2003, Wendy became an Assistant Professor here at NC State the in the Fiber and Polymer Science Program and Textile Engineering Program in the Department of Textile Engineering, Chemistry, & Science.