Associate Professor of Chemical Engineering

Ph.D., Cornell University, 1993, Postdoctoral Fellow, University of California (Berkeley), 1993-1994, Research Fellow, California Institute of Technology, 1994-1996 

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For more information, please see the Jiang Group Home Page

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INTERESTS:

Interfacial Phenomena and Nanotechnology

Molecularly thin films exhibit many novel properties and are central to future technologies, such as nanobiodevices, biocompatible materials, drug delivery, novel separation, and microelectromechanical systems (MEMS). Advances in molecular simulation and microscopic experimental techniques have given scientists and engineers the power to characterize, design, and optimize new materials and chemicals. Our research program is aimed at understanding the interfacial phenomena and properties of chemical and biological systems at the molecular level using state-of-the-art molecular simulation and microscopic experimental techniques. The ability to control and manipulate nano-scale chemical, structural, biological, and tribological properties of surfaces will facilitate our effort to develop various future technologies for engineering applications.

Molecular simulations provide insights into various atomic-scale properties, guide the interpretation of experimental data and the design of new experiments, and enable the prediction of properties not accessible to current laboratory experiments. Examples of our simulation work include: (a) predicting the adsorbed amount, orientation, and conformation of biological macromolecules on surfaces using Monte Carlo (MC), molecular dynamics (MD) and Brownian dynamics (BD) simulation techniques, (b) designing nanopores for novel separation using grand canonical ensemble molecular dynamics (GCMD) simulation techniques, (c) interpreting scanning force microscopy experiments using hybrid molecular simulation techniques, and (d) studying nanotribology in MEMS systems using a combined MD and MC approach. In addition, force fields are developed from ab initio quantum mechanics for accurate simulations while new simulation methodologies (e.g., cell-multipole method) and high-performance computing (e.g., massively parallel computers) are used for large-scale simulations.

The SPM, including atomic force (AFM), friction force (FFM), chemical force (CFM) and scanning tunneling (STM) microscopes, provides atomic-scale resolution images and allows accurate measurements of the forces applied in the horizontal and normal directions to the surface as well. The strength of surface plasmon resonance (SPR) biosensors lies in the ability to use simple, yet robust optical techniques in order to detect a wide variety of agents concurrently and rapidly. Self-assembled monolayers (SAMs) are very attractive for the rational control of surface microenvironments at the molecular level. Examples of our experimental work include: (a) controlling and characterizing molecular-scale uniform mixed SAMs, (b) controlling and probing orientation and conformation of protein molecules on controlled surfaces for biosensors and biomaterials, (c) controlling and studying non-fouling surfaces, (d) detecting single-molecular interactions in immunoreactions, (e) developing surface functionalization techniques for multi-channel SPR biosensors for anti-terrorism and food safty monitoring, (f) developing DNA chips, and (g) measuring quantitatively friction and adhesion properties for MEMS applications.

Experimental and simulation studies complement each other, and comparison of the two frequently leads to important new insights.
 

S. Chen, Q. Yu, L. Li, C. L. Boozer, J. Homola, S. S. Yee, and S. Jiang, Detecting the Adsorption of Dye Molecules in Homogenous Poly(propylene imine) Dendrimer Monolayers by Surface Plasmon Resonance Sensor, Journal of the American Chemical Society, 124, 3395 (2002).

Y.S. Leng and S. Jiang, Dynamic Simulations of Adhesion and Friction in Chemical Force Microscopy, Journal of the American Chemical Society, 124, 11764 (2002).

S. Jiang, Molecular Simulation Studies of Self-Assembled Monolayers of Alkanethiols on Au(111), Molecular Physics, 100, 2261 (2002).

L. Li, S. Chen, S. Oh, and S. Jiang, In Situ Single-Molecule Detection of Antibody-Antigen Binding by Tapping-Mode Atomic Force Microscopy, Analytical Chemistry, 74, 6017 (2002).

J. Homola, J. Dostalek, S.F. Chen, A. Rasooly, S. Jiang, and S.S. Yee, Spectral Surface Plasmon Resonance Biosensor for Detection of Staphylococcal Enterotoxin B (SEB) in Milk, Journal of Food Microbiology, 75, 61 (2002).

L. Zhang, W.A. Goddard III, and  S. Jiang, Molecular Simulation Study of the c(4x2) Superlattice Structure of Alkanethiol Self-Assembled Monolayers on Au(111), Journal of Chemical Physics, 117, 7342 (2002).

L. Zhang, L. Li, S. Chen, and S. Jiang, Measurements of Friction and Adhesion for Alkyl Monolayers on Si(111) by Scanning Force Microscopy, Langmuir, 18, 5448 (2002).

L. Zhang and S. Jiang, Molecular Simulation Study of Nanoscale Friction for Alkyl Monolayers on Si(111), Journal of Chemical Physics, 117, 1804 (2002).

Q. Zhang, J. Zheng, A. Shevade, L. Zhang, S.H. Gehrke, G.S. Heffelfinger, and S. Jiang, Transport Diffusion of Liquid Water and Methanol Through Membranes, Journal of Chemical Physics, 117, 808 (2002).

Q. Yu, K.M. Jeerage, W.M. Steen, S. Jiang, and D.T. Schwartz, Structure-Dependent Solvent and Ion Intercalation in Reduced and Oxidized Nickel Hexacyanoferrate, Journal of the Electrochemical Society, 149, E195 (2002).

C.L. Boozer, Q. Yu, S. Chen, C.Y. Lee, J. Homola, S.S. Yee, and S. Jiang, Surface Functionalization for Self-Referencing Surface Plasmon Resonance (SPR) Biosensors by Multi-Step Self Assembly, Submitted to Sensor and Actuator B, 2002 (accepted).

J. Zhou, H.K. Tsao, Y.J. Sheng, and S. Jiang, Adsorption and Orientation of Model Antibodies on Charged Surfaces: A Monte Carlo Simulation Study, Submitted to Biophys. J. 2002 (accepted).