Read by QxMD icon Read

Journal of Materials Chemistry

Siyoung Choi, William L Murphy
Previous studies have demonstrated the influence of calcium phosphate (CaP) mineral coating characteristics on cell attachment, proliferation, and differentiation. However, the wide range of mineral properties that can potentially influence cell behavior calls for an efficient platform to screen for the effects of specific mineral properties. To address this need, we have developed an efficient well-plate format to probe for the effects of mineral coating properties on stem cell behavior. Specifically, here we systematically controlled mineral coating morphology by modulating ion concentrations in modified simulated body fluids (mSBF) during mineral nucleation and growth...
December 28, 2012: Journal of Materials Chemistry
Nancy Hom, Kinjal R Mehta, Tsengming Chou, Amy B Foraker, Frances M Brodsky, Kent Kirshenbaum, Jin K Montclare
Recombinant clathrin protein fragments form assemblies that template gold nanocrystals in an array across the latticed surface. The nanocrystals exhibit unusual anisotropic morphologies with long range ordering, both of which are dependent upon the presence of a hexahistidine tag on the clathrin heavy chain fragments.
December 28, 2012: Journal of Materials Chemistry
Sai Archana Krovi, Elden P Swindell, Thomas V O'Halloran, Sonbinh T Nguyen
Polymer nanoparticles (PNPs) possessing a high density of drug payload have been successfully stabilized against aggregation in biological buffers after amine modification, which renders these PNPs positively charged. The resulting charge-stabilized PNPs retain their original narrow particle size distributions and well-defined spherical morphologies. This stabilization allows these PNPs to have an improved anti-proliferative effect on MDA-MB-231-Br human breast cancer cells compared to non-functionalized PNPs...
December 28, 2012: Journal of Materials Chemistry
Jason J Davis, Wen-Yen Huang, Gemma-Louise Davies
In tuning the sub-particle localisation of Gd(III) binding macrocycles within a mesoporous scaffold, nanoparticle contrast agents of unprecedented relaxivity and low Gd(III) loadings can be realised.
October 16, 2012: Journal of Materials Chemistry
Hyun-Su Lee, Michael Q Yee, Yonaton Y Eckmann, Noreen J Hickok, David M Eckmann, Russell J Composto
This study investigates the swelling of grafted polycationic brushes as a function of pH and anion type. The brushes are chitosan (CH) and chitosans with 27% and 51% degree of substitution (DS) of quaternary ammonium salt, denoted as CH-Q(25) and CH-Q(50), respectively. The water content and swelling behaviors are monitored using in situ quartz-crystal microbalance with dissipation (QCM-D). The pH varies from ~3.5 to 8.5, and the counter anion types include chloride, acetate, and citrate. At fixed pH, the water content and brush swelling increase as the DS increases...
October 7, 2012: Journal of Materials Chemistry
Jordan Raphel, Andreina Parisi-Amon, Sarah Heilshorn
Photocrosslinkable, protein-engineered biomaterials combine a rapid, controllable, cytocompatible crosslinking method with a modular design strategy to create a new family of bioactive materials. These materials have a wide range of biomedical applications, including the development of bioactive implant coatings, drug delivery vehicles, and tissue engineering scaffolds. We present the successful functionalization of a bioactive elastin-like protein with photoreactive diazirine moieties. Scalable synthesis is achieved using a standard recombinant protein expression host followed by site-specific modification of lysine residues with a heterobifunctional N-hydroxysuccinimide ester-diazirine crosslinker...
October 7, 2012: Journal of Materials Chemistry
Haiqing Yin, Han Chang Kang, Kang Moo Huh, You Han Bae
Motivated by the limitations of liposomal drug delivery systems, we designed a novel histidine-based AB(2)-miktoarm polymer (mPEG-b-(polyHis)(2)) equipped with a phospholipid-mimic structure, low cytotoxicity, and pH-sensitivity. Using "core-first" click chemistry and ring-opening polymerization, mPEG(2kDa)-b-(polyHis(29kDa))(2) was successfully synthesized with a narrow molecular weight distribution (1.14). In borate buffer (pH 9), the miktoarm polymer self-assembled to form a nano-sized polymersome with a hydrodynamic radius of 70...
September 28, 2012: Journal of Materials Chemistry
V Chandana Epa, Jing Yang, Ying Mei, Andrew L Hook, Robert Langer, Daniel G Anderson, Martyn C Davies, Morgan R Alexander, David A Winkler
Designing materials to control biology is an intense focus of biomaterials and regenerative medicine research. Discovering and designing materials with appropriate biological compatibility or active control of cells and tissues is being increasingly undertaken using high throughput synthesis and assessment methods. We report a relatively simple but powerful machine-learning method of generating models that link microscopic or molecular properties of polymers or other materials to their biological effects. We illustrate the potential of these methods by developing the first robust, predictive, quantitative, and purely computational models of adhesion of human embryonic stem cell embryoid bodies (hEB) to the surfaces of a 496-member polymer micro array library...
September 18, 2012: Journal of Materials Chemistry
Daniela F Coutinho, Shilpa Sant, Mojdeh Shakiba, Ben Wang, Manuela E Gomes, Nuno M Neves, Rui L Reis, Ali Khademhosseini
Chitosan (CHT) based polyelectrolyte complexes (PECs) have been receiving great attention for tissue engineering approaches. These hydrogels are held together by ionic forces and can be disrupted by changes in physiological conditions. In this study, we present a new class of CHT-based PEC hydrogels amenable to stabilization by chemical crosslinking. The photocrosslinkable anionic methacrylated gellan gum (MeGG) was complexed with cationic CHT and exposed to light, forming a PEC hydrogel. The chemical characterization of the photocrosslinkable PEC hydrogel by Fourier transform infrared spectroscopy (FTIR) revealed absorption peaks specific to the raw polymers...
September 7, 2012: Journal of Materials Chemistry
Gregory J Hardy, Rahul Nayak, S Munir Alam, Joseph G Shapter, Frank Heinrich, Stefan Zauscher
In this study, we present a technique to create a complex, high cholesterol-containing supported lipid bilayers (SLBs) using α-helical (AH) peptide-induced vesicle fusion. Vesicles consisting of POPC : POPE : POPS : SM : Chol (9.35 : 19.25 : 8.25 : 18.15 : 45.00) were used to form a SLB that models the native composition of the human immunodeficiency virus-1 (HIV-1) lipid envelope. In the absence of AH peptides, these biomimetic vesicles fail to form a complete SLB. We verified and characterized AH peptide-induced vesicle fusion by quartz crystal microbalance with dissipation monitoring, neutron reflectivity, and atomic force microscopy...
August 28, 2012: Journal of Materials Chemistry
Dong Soo Hwang, Matthew J Harrington, Qingye Lu, Admir Masic, Hongbo Zeng, J Herbert Waite
Marine mussels utilize a variety of DOPA-rich proteins for purposes of underwater adhesion, as well as for creating hard and flexible surface coatings for their tough and stretchy byssal fibers. In the present study, moderately strong, yet reversible wet adhesion between the protective mussel coating protein, mcfp-1, and amorphous titania was measured with a surface force apparatus (SFA). In parallel, resonance Raman spectroscopy was employed to identify the presence of bidentate DOPA-Ti coordination bonds at the TiO(2)-protein interface, suggesting that catechol-TiO(2) complexation contributes to the observed reversible wet adhesion...
August 21, 2012: Journal of Materials Chemistry
Hongyu Chen, Daniel C Colvin, Bin Qi, Thomas Moore, Jian He, O Thompson Mefford, Frank Alexis, John C Gore, Jeffrey N Anker
When X-rays irradiate radioluminescence nanoparticles, they generate visible and near infrared light that can penetrate through centimeters of tissue. X-ray luminescence tomography (XLT) maps the location of these radioluminescent contrast agents at high resolution by scanning a narrow X-ray beam through the tissue sample and collecting the luminescence at every position. Adding magnetic functionality to these radioluminescent particles would enable them to be guided, oriented, and heated using external magnetic fields, while their location and spectrum could be imaged with XLT and complementary magnetic resonance imaging...
July 7, 2012: Journal of Materials Chemistry
Hongguang Lu, Fengyu Su, Qian Mei, Yanqing Tian, Wenjing Tian, Roger H Johnson, Deirdre R Meldrum
Two new series of aggregation-induced emission (AIE) fluorophore-containing amphiphilic copolymers possessing the segments of a monomeric AIE fluorophore, N-(2-hydroxypropyl)methacrylamide (HPMA), [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MATMA), and/or 2,2,2-trifluoroethyl methacrylate (TFEMA) were synthesized. Photophysical properties were investigated using UV-Vis absorbance and fluorescence spectrofluorometry. The increases of molar fractions of the hydrophobic AIE fluorophores and/or the trifluoroethyl moieties result in the higher quantum yields of the AIE fluorophores in the polymers...
May 1, 2012: Journal of Materials Chemistry
Lixin Liu, Hailong Zhou, Rui Cheng, Yu Chen, Yung-Chen Lin, Yongquan Qu, Jingwei Bai, Ivan A Ivanov, Gang Liu, Yu Huang, Xiangfeng Duan
Graphene has attracted considerable interest as a potential material for future electronics. Although mechanical peel is known to produce high quality graphene flakes, practical applications require continuous graphene layers over a large area. The catalyst-assisted chemical vapor deposition (CVD) is a promising synthetic method to deliver wafer-sized graphene. Here we present a systematic study on the nucleation and growth of crystallized graphene domains in an atmospheric pressure chemical vapor deposition (APCVD) process...
January 28, 2012: Journal of Materials Chemistry
Justin T Koepsel, Patrick T Brown, Samuel G Loveland, Wan-Ju Li, William L Murphy
Self-assembled monolayers (SAMs) of alkanethiolates on gold are chemically defined substrates that can be used to evaluate the effects of an immobilized biomolecule. However, the types of biomolecules that can influence stem cell behavior are numerous and inter-related, and efficient experimental formats are a critical need. Here we employed a SAM array technology to investigate the effects of multiple, distinct peptides and peptide combinations on human mesenchymal stem cell (hMSC) behavior. Specifically, we characterized the conjugation of peptide mixtures to SAM arrays and then investigated the combined effects of a bone morphogenic protein receptor-binding peptide (BR-BP), a heparin proteoglycan-binding peptide (HPG-BP), and varied densities of the integrin-binding ligand Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP) on hMSC surface coverage and alkaline phosphatase activity...
2012: Journal of Materials Chemistry
Carsten O Schirra, Angana Senpan, Ewald Roessl, Axel Thran, Allen J Stacy, Lina Wu, Roland Proska, Dipanjan Pan
Spectral CT is the newest advancement in CT imaging technology, which enhances traditional CT images with the capability to image and quantify certain elements based on their distinctive K-edge energies. K-edge imaging feature recognizes high accumulations of targeted elements and presents them as colorized voxels against the normal grayscale X-ray background offering promise to overcome the relatively low inherent contrast within soft tissue and distinguish the high attenuation of calcium from contrast enhanced targets...
January 1, 2012: Journal of Materials Chemistry
Wenbing Li, Wentong Lu, Zhen Fan, Xianchun Zhu, Aisha Reed, Brandon Newton, Yazhou Zhang, Shavelle Courtney, Papireddy T Tiyyagura, Shufang Li, Ebonie Butler, Hongtao Yu, Paresh C Ray, Ruomei Gao
The synthesis and characterization of bare silica (4 nm in diameter) nanoparticle-attached meso-tetra(N-methyl-4-pyridyl)porphine (SiO(2)-TMPyP, 6 nm in diameter) are described for pH-controllable photosensitization. Distinguished from organosilanes, SiO(2) nanoparticles were functionalized as a potential quencher of triplet TMPyP and/or singlet oxygen ((1)O(2)) at alkaline pH, thereby turning off sensitizer photoactivity. In weak acidic solutions, TMPyP was released from SiO(2) surface for efficient production of (1)O(2)...
January 1, 2012: Journal of Materials Chemistry
Jason Christopher Dyke, Kelly Jane Knight, Huaxing Zhou, Chi-Kai Chiu, Ching-Chang Ko, Wei You
Causes of bone deficiency are numerous, but biomimetic alloplastic grafts provide an alternative to repair tissue naturally. Previously, a hydroxyapatite-gelatin modified siloxane (HAp-Gemosil) composite was prepared by cross-linking (N, N'-bis[(3-trimethoxysilyl)propyl]ethylene diamine (enTMOS) around the HAp-Gel nanocomposite particles, to mimic the natural composition and properties of bone. However, the tensile strength remained too low for many orthopedic applications. It was hypothesized that incorporating a polymer chain into the composite could help improve long range interaction...
January 1, 2012: Journal of Materials Chemistry
Kun Liu, Mark E Meyerhoff
A new, stable and highly efficient Cu(2+)-cyclen-polyurethane material is described and shown to exhibit improved performance compared to prior materials for the catalytic decomposition of S-nitrosothiols to physiologically active nitric oxide.
January 1, 2012: Journal of Materials Chemistry
Kathryn E Dekrafft, William S Boyle, Laurel M Burk, Otto Z Zhou, Wenbin Lin
Nanoscale metal-organic frameworks (NMOFs) of the UiO-66 structure containing high Zr (37 wt%) and Hf (57 wt%) content were synthesized and characterized, and their potential as contrast agents for X-ray computed tomography (CT) imaging was evaluated. Hf-NMOFs of different sizes were coated with silica and poly(ethylene glycol) (PEG) to enhance biocompatibility, and were used for in vivo CT imaging of mice, showing increased attenuation in the liver and spleen.
January 1, 2012: Journal of Materials Chemistry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"