@article {2698,
	title = {Barrier Capacity of Hydrophilic Polymer Brushes To Prevent Hydrophobic Interactions: Effect of Graft Density and Hydrophilicity},
	journal = {Macromolecules},
	volume = {42},
	number = {13},
	year = {2009},
	note = {ISI Document Delivery No.: 472NJTimes Cited: 7Cited Reference Count: 57Zou, Yuquan Rossi, Nicholas A. A. Kizhakkedathu, Jayachandran N. Brooks, Donald E.},
	month = {Jul},
	pages = {4817-4828},
	type = {Article},
	abstract = {The performance of biomaterials in contact with biological systems can be greatly affected by hydrophobic interactions at the interface between the biomaterial surface and surrounding biomolecules. Polymer brushes can function as a protective layer, preventing such interfacial hydrophobic interactions. In this paper, a systematic study of the barrier properties of a hydrophilic polymer brush is made by investigating the influence of graft density and its chemical nature (hydrophilicity/hydrophobicity) on hydrophobic interactions with the surface. To achieve this, it series of novel thermoresponsive poly-N-[(2,2-dimethyl-1,3-dioxolane)methyl]acrylamide (PDMDOMA) polymer brushes were grown from silicon wafers via surface-initiated atom transfer radical polymerization. Without changing graft density or degree of polymerization, the hydrophilicity of the PDMDOMA brushes was manipulated by partial or complete hydrolysis or the pendent dioxolane moieties. A lower critical solution temperature (LCST) was observed at 22-24 degrees C, below which the PDMDOMA brush was Found to be in a hydrated state (amphiphilic), while at temperatures above the LCST, the PDMDOMA brush formed a collapsed. more hydrophobic structure. A physical method was developed to analyze the ability of these brushes to act as a barrier against hydrophobic interactions based on AFM force-distance measurements. The adhesive forces between the Si3N4 tip and the silicon wafer surface upon (a) modification with ATRP initiator, (b) grafting of PDMDOMA brushes, and (c) partial and complete hydrolysis of PDMDOMA were investigated. Hydrophobic interactions decreased after each modification, while graft density and the degree of hydrolysis increased the barrier function of the surface layer. In particular, when graft density was above 0.22 chains/nm(2), the barrier capacity completely counteracted the hydrophobic interactions, as evidenced from the disappearance of the adhesive force in AFM measurements. Further Studies revealed that the barrier property its assessed by AFM correlated well with the wettability of the surfaces.},
	keywords = {ATOMIC-FORCE MICROSCOPY, BLOOD-PLASMA, CELL-ADHESION, CHAIN-LENGTH, HUMAN, MOLECULAR-WEIGHT, protein adsorption, SERUM-ALBUMIN, SINGLE-MOLECULE, SURFACE, TRANSFER RADICAL POLYMERIZATION},
	isbn = {0024-9297},
	url = {<Go to ISI>://000268138500067},
	author = {Zou, Y. Q. and Rossi, N. A. A. and Kizhakkedathu, J. N. and Brooks, D. E.}
}
@article {2697,
	title = {Surface Modification of Polyvinyl Chloride Sheets via Growth of Hydrophilic Polymer Brushes},
	journal = {Macromolecules},
	volume = {42},
	number = {9},
	year = {2009},
	note = {ISI Document Delivery No.: 441PNTimes Cited: 7Cited Reference Count: 65Zou, Yuquan Kizhakkedathu, Jayachandran N. Brooks, Donald E.},
	month = {May},
	pages = {3258-3268},
	type = {Article},
	abstract = {Poly(N,N-dimethylacrylamide) (PDMA) brushes were successfully grown from polyvinyl chloride (uPVC) sheets via well-controlled surface-initiated atom transfer radical polymerization (SI-ATRP). An ATRP initiator containing a chloropropionate moiety was chemically tethered onto the surface of PVC via it novel wet chemical modification. Negatively charged sulfate groups were introduced to facilitate polymerization. By incorporating a chemically cleavable group into the initiator, molecular weight, polydispersity and graft density of a series of PDMA brushes synthesized on the flat surface were unambiguously characterized for the first time by gel permeation chromatography. ATR-FTIR, contact angle, SEM and AFM were used to characterize the PDMA grafted surfaces. Reaction conditions Such as monomer concentration, reaction time, copper(II) concentration and salt additives were varied to systematically investigate their effects on molecular weight and graft density of the PDMA grafted from PVC. Molecular weights of grafted PDMA brushes varied from ca. 20 000 to 2 170 000 Da, while craft density ranged from 0.08 to 1.13 chains/nm(2). Polydispersity of grafted PDMA brushes was controlled between 1.20 and 1.60 by Cu(II) complex addition. Kinetic studies revealed that the surface initiation was a slow process and graft density increased during the reaction. The brush uniformity increased with increasing reaction time. Reinitiation of the obtained PDMA brushes was demonstrated, suggesting that the polymerization is "living". The successful growth of a PDMA-b-poly(N-isopropylacrylamide) (PNIPAM) copolymer brush was verified by GPC and AFM.},
	keywords = {AQUEOUS ATRP, ATOMIC-FORCE MICROSCOPY, CARBON NANOTUBES, COPOLYMER BRUSHES, density, GLYCOL), GRAFT, PLASMA-PROTEIN ADSORPTION, POLY(ETHYLENE, SELF-ASSEMBLED MONOLAYERS, SERUM-ALBUMIN, TRANSFER RADICAL POLYMERIZATION},
	isbn = {0024-9297},
	url = {<Go to ISI>://000265781300007},
	author = {Zou, Y. Q. and Kizhakkedathu, J. N. and Brooks, D. E.}
}
@article {648,
	title = {Revealing system dynamics through decomposition of the perturbation domain in two-dimensional correlation spectroscopy},
	journal = {Applied Spectroscopy},
	volume = {57},
	number = {12},
	year = {2003},
	note = {ISI Document Delivery No.: 753MHTimes Cited: 5Cited Reference Count: 36},
	month = {Dec},
	pages = {1551-1560},
	type = {Article},
	abstract = {A technique is presented to simply and effectively decompose the perturbation domain in two-dimensional (2D) correlation maps calculated on a given set of vibrational spectra. Decomposition of the perturbation domain exposes a wealth of kinetic information complementary to the information extracted from conventional 2D correlation spectroscopy. It is shown that the technique produces "perturbation profile maps" that can be utilized in both the interpretation of the conventional 2D correlation maps and the independent kinetic analysis of the given system. Discrimination between spectral features exhibiting similar, but not identical, dynamics is facilitated by the decomposition, and spectral features exhibiting identical dynamics over the perturbation interval are quickly identified. Spectral features exhibiting similar dynamics over only a sub-range of the full perturbation are also identifiable. Interpretation of phase information illuminated in synchronous and asynchronous maps is simplified. Comparison between similar spectral features present in different samples is facilitated with the technique. The simplicity and ease of implementation of the technique make decomposition of the perturbation domain a valuable addition to the tools available in 2D correlation analysis.},
	keywords = {cross-correlation, FT-RAMAN, HUMAN, INFRARED CORRELATION SPECTROSCOPY, multivariate data, POLYACRYLAMIDE GELS, POLYMER GEL DOSIMETERS, RADIATION-DOSIMETRY, Raman spectroscopy, SAMPLE-SAMPLE, SECONDARY STRUCTURE, SERUM-ALBUMIN, SPECTRA, STRUCTURAL-CHANGES, two-dimensional correlation spectroscopy},
	isbn = {0003-7028},
	url = {<Go to ISI>://000187234800013},
	author = {Jirasek, A. and Schulze, G. and Blades, M. W. and Turner, R. F. B.}
}
@article {648,
	title = {Revealing system dynamics through decomposition of the perturbation domain in two-dimensional correlation spectroscopy},
	journal = {Applied Spectroscopy},
	volume = {57},
	number = {12},
	year = {2003},
	note = {ISI Document Delivery No.: 753MHTimes Cited: 5Cited Reference Count: 36},
	month = {Dec},
	pages = {1551-1560},
	type = {Article},
	abstract = {A technique is presented to simply and effectively decompose the perturbation domain in two-dimensional (2D) correlation maps calculated on a given set of vibrational spectra. Decomposition of the perturbation domain exposes a wealth of kinetic information complementary to the information extracted from conventional 2D correlation spectroscopy. It is shown that the technique produces "perturbation profile maps" that can be utilized in both the interpretation of the conventional 2D correlation maps and the independent kinetic analysis of the given system. Discrimination between spectral features exhibiting similar, but not identical, dynamics is facilitated by the decomposition, and spectral features exhibiting identical dynamics over the perturbation interval are quickly identified. Spectral features exhibiting similar dynamics over only a sub-range of the full perturbation are also identifiable. Interpretation of phase information illuminated in synchronous and asynchronous maps is simplified. Comparison between similar spectral features present in different samples is facilitated with the technique. The simplicity and ease of implementation of the technique make decomposition of the perturbation domain a valuable addition to the tools available in 2D correlation analysis.},
	keywords = {cross-correlation, FT-RAMAN, HUMAN, INFRARED CORRELATION SPECTROSCOPY, multivariate data, POLYACRYLAMIDE GELS, POLYMER GEL DOSIMETERS, RADIATION-DOSIMETRY, Raman spectroscopy, SAMPLE-SAMPLE, SECONDARY STRUCTURE, SERUM-ALBUMIN, SPECTRA, STRUCTURAL-CHANGES, two-dimensional correlation spectroscopy},
	isbn = {0003-7028},
	url = {<Go to ISI>://000187234800013},
	author = {Jirasek, A. and Schulze, G. and Blades, M. W. and Turner, R. F. B.}
}
@article {4305,
	title = {Optimization and immunological characterization of a photochemically coupled lysergic acid diethylamide (LSD) immunogen},
	journal = {Bioconjugate Chemistry},
	volume = {9},
	number = {5},
	year = {1998},
	note = {ISI Document Delivery No.: 125MYTimes Cited: 2Cited Reference Count: 41},
	month = {Sep-Oct},
	pages = {596-603},
	type = {Article},
	abstract = {A photoreactive heterobifunctional linker was used to prepare an immunogen in which lysergic acid diethylamide was indirectly coupled to keyhole limpet hemocyanin at multiple sites on the drug. It was possible to attach approximately 35 drug molecules to each protein using approximately equal amounts of both species during the reaction. The presence of buffer components or water severely compromised reaction efficiency, as estimated from the molar substitution ratio. Factors such as excess linker, pH, irradiation of dry matrix in the absence of buffer, and the drug/protein ratio used during photolysis were shown to have pronounced effects on reaction efficiency. Structural insights regarding immunogen coupling were obtained by determining the specificities of antibodies which were raised against the immunogen. Cross-reactivity data indicated that haptenation of protein likely occurred at positions N1 and N6 of lysergic acid diethylamide, which is plausible given the electrophilicity of the photogenerated aryl nitrene.},
	keywords = {BINDING, CROSS-LINKING REAGENTS, EPITOPE, FUNCTIONALIZED PERFLUOROPHENYL AZIDES, IMMUNOASSAY, IONIZATION MASS-SPECTROMETRY, photolysis, PROTEIN, RADIOIMMUNOASSAY, SERUM-ALBUMIN},
	isbn = {1043-1802},
	url = {<Go to ISI>://000076242400008},
	author = {Kerrigan, S. and Brooks, D. E.}
}
