@article {292,
	title = {Why is THz Sensitive to Protein Functional States? Oxidation State of Cytochrome C},
	journal = {Terahertz Science and Technology},
	volume = {3},
	year = {2010},
	chapter = {149-162},
	abstract = {<p>We investigate the presence of structural collective motions on a picosecond time scale for the heme protein, cytochrome c, as a function of oxidation and hydration, using terahertz (THz) time-domain spectroscopy and molecular dynamics simulations. Structural collective mode frequencies have been calculated to lie in this frequency range, and the density of states can be considered a measure of flexibility. A dramatic increase in the THz response occurs with oxidation, with the largest increase for lowest hydrations and highest frequencies. For both oxidation states the measured THz response rapidly increases with hydration saturating above ~25\% (g H<sub>2</sub>O/g protein), in contrast to the rapid turn-on in dynamics observed at this hydration level for other proteins. Quasi-harmonic collective vibrational modes and dipole-dipole correlation functions are calculated from the molecular dynamics trajectories. The collective mode density of states alone reproduces the measured hydration dependence providing strong evidence of the existence of these collective motions. The large oxidation dependence is reproduced only by the dipole-dipole correlation function, indicating the contrast arises from diffusive motions consistent with structural changes occurring in the vicinity of a buried internal water molecule.</p>},
	doi = {10.11906/TST.149-162.2010.12.15},
	url = {http://www.tstnetwork.org/10.11906/TST.149-162.2010.12.15/},
	author = {He,Y. and Chen, J.-Y. and Knab, J. R. and Zheng, W. and Markelz, A.G.}
}
@inbook {303,
	title = {Development of Tagless Biosensors for Detecting the Presence of Pathogens},
	booktitle = {Terahertz Frequency Detection and Identification of Materials and Objects},
	volume = {ed X.-C. Zhang, R. E. Miles, H. Eisele and A. Krotkus},
	year = {2007},
	pages = {123-134},
	publisher = {Springer},
	organization = {Springer},
	chapter = {9},
	address = {Dordrecht, The Netherlands},
	author = {Markelz, A. G. and Chen, J.-Y. and Knab, J. R. and He, Y. and Ye, S.}
}
@proceedings {308,
	title = {Ultrafast Carriers Dynamics in GaSb/Mn Random Alloys},
	year = {2006},
	address = {Vienna Austria},
	doi = {10.1063/1.2730382},
	author = {Ye, S. and Knab, J. and Chen, J.-Y. and Wang, S. and Cheon, M. and Luo, H. and Markelz, A. G.}
}
@proceedings {309,
	title = {Using terahertz spectroscopy as a protein binding assay},
	volume = {Proc SPIE 6080,},
	year = {2006},
	month = {02/2006},
	pages = {35-42},
	address = { San Jose, California, United States},
	abstract = {<p>The vibrational modes corresponding to protein tertiary structural motion lay in the far infrared or terahertz frequency range. These collective large scale motions depend on global structure and thus will necessarily be perturbed by ligand binding events. We discuss the use of terahertz dielectric spectroscopy to measure these vibrational modes and the sensitivity of the technique to changes in protein conformation, oxidation state and environment. A challenge of applying this sensitivity as a spectroscopic assay for ligand binding is the sensitivity of the technique to both bulk water and water bound to the protein. This sensitivity can entirely obscure the signal from the protein or protein-ligand complex itself, thus necessitating sophisticated sample preparation making the technique impractical for industrial applications. We discuss methods to overcome this background and demonstrate how terahertz spectroscopy can be used to quickly assay protein binding for proteomics and pharmaceutical research.</p>},
	doi = {10.1117/12.664098},
	author = {Chen, J.-Y. and Knab, J. R. and Ye, S. and He, Y. and Markelz, A. G.}
}
@proceedings {311,
	title = {Measuring Protein Flexibility with Terahertz Spectroscopy: Basic Research and Applications},
	year = {2004},
	month = {06/2004},
	address = {San Diego, CA},
	doi = {10.1109/LEOSST.2004.1338649},
	author = {Markelz, A. G. and Chen, J.-Y. and Knab, J. R. and Maeder, M.}
}
@proceedings {312,
	title = {Thz Dielectric Response As A Function Of Protein Hydration: Intramolecular Coupling Contribution},
	year = {2004},
	month = {10/2004},
	address = {Philadelphia, PA},
	author = {Markelz, A. G. and Chen, J.-Y. and Knab, J. R. and Maeder, M.}
}
@proceedings {313,
	title = {Biosensing with Terahertz Spectroscopy:  Ligand Binding Effects},
	year = {2003},
	address = {Santa Barbara, CA},
	author = {Chen, J.-Y. and Cerne, J. and Markelz, A. G.}
}
@proceedings {314,
	title = {Terahertz Biosensors based on Xerogel Substrates},
	year = {2003},
	address = {Santa Barbara, CA},
	author = {Chen, J.-Y. and Cox, W. and Bright, F. V. and Cerne, J. and Markelz, A. G.}
}
@proceedings {315,
	title = {Ultrafast THz spectroscopy of photoactive biomolecules},
	year = {2003},
	month = {01/2003},
	pages = {146-153},
	address = {San Jose, California},
	author = {Chen, J.-Y. and Whitmire, S. E. and Markelz, A. G. and Hillebrecht, J. R. and Birge, R. R.}
}
