Read by QxMD icon Read


Kun Zhang, Yongguang Jia, I-Huang Tsai, Satu Strandman, Li Ren, Liangzhi Hong, Guangzhao Zhang, Ying Guan, Yongjun Zhang, Julian X X Zhu
Natural compounds glucosamine and cholic acid have been used to make acrylic monomers which are subsequently used to prepare amphiphilic block copolymers by reversible addition-fragmentation chain transfer (RAFT) polymerization. Despite the striking difference in polarity and solubility, three diblock copolymers consisting of glucosamine and cholic acid pendants with different hydrophilic and hydrophobic chain lengths have been synthesized without the use of protecting groups. They are shown to self-assemble into polymeric micelles with a "bitter" bile acid core and "sweet" sugar shell in aqueous solutions as evidenced by dynamic light scattering and transmission electron microscopy...
January 17, 2017: Biomacromolecules
Sarah R MacEwan, Isaac Weitzhandler, Ingo Hoffmann, Jan Genzer, Michael Gradzielski, Ashutosh Chilkoti
This paper investigates how the properties of multi-block copolypeptides can be tuned by their block architecture, defined by the size and distribution of blocks along the polymer chain. These parameters were explored by the precise - genetically encoded - synthesis of recombinant elastin-like polypeptides (ELPs). A family of ELPs was synthesized in which the composition and length were conserved while the block length and distribution were varied, thus creating eleven ELPs with unique block architectures. To our knowledge, these polymers are unprecedented in their intricately and precisely varied architectures...
January 17, 2017: Biomacromolecules
Mehedi Reza, Carlo Giuseppe Bertinetto, Janne Ruokolainen, Tapani Vuorinen
The ultrastructural organization of cellulose elementary fibrils (EF) in wood cell wall is considered to be the prime factor regulating the material characteristics of wood in micro to macro levels and the conversion of delignified wood fibers into various products. Specifically, the complex assembly of EFs in wood cell wall limits its swellability, solubility and reactivity e.g., in dissolution of cellulose for regeneration of textile fibers, fibril separation for the manufacture of nanocellulose, and enzymatic hydrolysis of cellulose into sugars for their subsequent fermentation to various products, like ethanol for future fossil fuels replacement...
January 13, 2017: Biomacromolecules
Mohamed Jebrane, Nasko Terziev, Ivo Heinmaa
Fatty acid cellulose esters (FACEs), which have been identified recently as sustainable film materials, are conventionally synthesized by the use of the reaction with acyl chloride/anhydride pyridine in the presence of LiCl/N,N-dimethylacetamide. In this study, we have developed a new synthetic route to FACEs using a vinyl ester of long chain fatty acid, which is an excellent biobased and highly reactive reagent, for the functionalization of cellulose. The developed method involves the synthesis of the long aliphatic fatty acid vinyl ester via a transition-metal-catalyzed transvinylation reaction between vinyl acetate and the fatty acid, followed by its subsequent reaction with cellulose to yield FACEs...
January 13, 2017: Biomacromolecules
Chad S Cummings, Alan S Campbell, Stefanie L Baker, Sheiliza Carmali, Hironobu Murata, Alan J Russell
The reduced immunogenicity and increased stability of protein-polymer conjugates has made their use in therapeutic applications particularly attractive. However, the physicochemical interactions between polymer and protein, as well as the effect of this interaction on protein activity and stability, are still not fully understood. In this work, polymer-based protein engineering was used to examine the role of polymer physiochemical properties on the activity and stability of the chymotrypsin-polymer conjugates and their degree of binding to intestinal mucin...
January 12, 2017: Biomacromolecules
Eda Adal, Amin Sadeghpour, Simon D A Connell, Michael Rappolt, Esra Ibanoglu, Anwesha Sarkar
Associative electrostatic interactions between two oppositely charged globular proteins, lactoferrin (LF) and pea protein isolate (PPI), the latter being a mixture of vicilin, legumin and convicilin, was studied with a specific PPI/ LF molar ratio at room temperature. Structural aspects of the electrostatic complexes probed at different length scales were investigated as a function of pH by means of different complementary techniques, namely with dynamic light scattering, small angle X-ray scattering (SAXS), turbidity measurements and atomic force microscopy (AFM)...
January 12, 2017: Biomacromolecules
Ann-Christine Albertsson
No abstract text is available yet for this article.
January 11, 2017: Biomacromolecules
Rosine Petitdemange, Elisabeth Garanger, Laure Bataille, Katell Bathany, Bertrand Garbay, Timothy J Deming, Sebastien Lecommandoux
We have designed and prepared a recombinant elastin-like polypeptide (ELP) containing precisely positioned methionine residues, and performed the selective and complete oxidation of its methionine thioether groups to both sulfoxide and sulfone derivatives. Since these oxidation reactions substantially increase methionine residue polarity, they were found to be a useful means to precisely adjust the temperature responsive behavior of ELPs in aqueous solutions. In particular, lower critical solution temperatures were found to be elevated in oxidized sample solutions, but were not eliminated...
January 11, 2017: Biomacromolecules
Qiong Dai, Junling Guo, Yan Yan, Ching-Seng Ang, Nadja Bertleff-Zieschang, Frank Caruso
A protein corona, which forms on engineered particles as soon as they are introduced into biological environments, is known to provide particles with a "biological identity". Protein coronas derived from various biological environments have been demonstrated to alter the cell internalization mechanism, to diminish targeting ability and to induce nanoparticle aggregation. So far, most of these studies have challenged engineered particles with a static biological environment. However, the extracellular environment is highly dynamic due to the process termed "cell-conditioning", in which cells deplete and secrete biomolecules...
January 11, 2017: Biomacromolecules
Marcelo A da Silva, Samuel Lenton, Matthew Hughes, David J Brockwell, Lorna Dougan
The native states of proteins generally have stable well-defined folded structures endowing these biomolecules with specific functionality and molecular recognition abilities. Here we explore the potential of using folded globular polyproteins as building blocks for hydrogels. Photochemically cross-linked hydrogels were produced from polyproteins containing either five domains of I27 ((I27)5), protein L ((pL)5), or a 1:1 blend of these proteins. SAXS analysis showed that (I27)5 exists as a single rod-like structure, while (pL)5 shows signatures of self-aggregation in solution...
January 11, 2017: Biomacromolecules
Jie Gao, Claire Tang, Andrew M Smith, Aline Fiona Miller, Alberto Saiani
Self-assembling peptide based hydrogels have encountered increasing interest in the recent years as scaffolds for 3D cell culture or for controlled drug delivery. One of the main challenges is the fine control of the mechanical properties of these materials. The bulk properties of hydrogel not only depend on the intrinsic properties of the fibres but also on the network topology formed. In this work we show how fibre-fibre interactions can be manipulated by design to control the final hydrogels network topology and therefore control the final properties of the material...
January 9, 2017: Biomacromolecules
Yi Deng, Yuanyi Yang, Shicheng Wei
Realization of clinical potential of human pluripotent stem cells (hPSCs) in bone regenerative medicine requires development of simple and safe biomaterials for expansion of hPSCs followed by directing their lineage commitment to osteoblasts. In the present study, a chemically defined peptide-decorated polycaprolactone (PCL) nanofibrous microenvironment was prepared through electrospinning technology and subsequent conjugation with vitronectin peptide to promote the culture and osteogenic potential of hPSCs in vitro...
January 9, 2017: Biomacromolecules
Jens Christoph Natterodt, Janak Sapkota, E Johan Foster, Christoph Weder
Cellulose nanocrystals (CNCs) are mechanically rigid, toxicologically benign, fiber-like nanoparticles. They can easily be extracted from renewable bio-sources and have attracted significant interest as reinforcing fillers in polymers. We here report the modification of CNCs with the 2-ureido-4[1H]pyrimidinone (UPy) motif as an adaptive compatibilizer, which permits the dispersion of UPy-modified CNCs in nonpolar as well as polar media. In toluene, the UPy motifs appear to form intra-CNC dimers, so that the particles are somewhat hydrophobized and well-dispersible in this nonpolar solvent...
January 9, 2017: Biomacromolecules
Amir Hossein Irani, Jessie L Owen, Davide Mercadante, Martin A K Williams
Homogalacturonans (HGs) are polysaccharide co-polymers of galacturonic acid and its methylesterified counterpart. The inter- and intra-molecular distributions of the methylesterifed residues are vital behaviour-determining characteristics of a sample's structure and much experimental effort has been directed to their measurement. While many techniques are able to measure the sample-averaged degree of methylesterification (DM), the measurement of inter- and intra-molecular charge distributions are challenging...
January 6, 2017: Biomacromolecules
Tamilselvan Mohan, Katrin Niegelhell, Chandran Nagaraj, David Reishofer, Stefan Spirk, Andrea Olschewski, Karin Stana Kleinschek, Rupert Johann Kargl
Polymer based biomaterials particularly polycaprolactone (PCL) are one of the most promising substrates for tissue engineering. The surface chemistry of these materials plays a major role since it governs protein adsorption, cell adhesion, viability, degradation and biocompatibility in the first place. This study correlates the interaction of the most abundant serum proteins (albumin, immunoglobulins, fibrinogen) with the surface properties of PCL and its influence on the morphology and metabolic activity of primary human arterial endothelial cells that are seeded on the materials...
January 5, 2017: Biomacromolecules
Satoko Suzuki, Shoko Itakura, Ryo Matsui, Kayoko Nakayama, Takayuki Nishi, Akinori Nishimoto, Susumu Hama, Kentaro Kogure
Delivery of anti-cancer drugs into tumor cores comprised of malignant cancer cells can result in potent therapeutic effects. However, conventional nanoparticle-based drug delivery systems used for cancer therapy often exhibit inefficient tumor-penetrating properties, thus suggesting the need to improve the functional design of such systems. Herein, we focus on the interactions between cancer cells and the extracellular matrix (ECM), and demonstrate that liposomes modified with slightly acidic pH-sensitive peptide (SAPSp-lipo) can penetrate in vivo tumor tissue and in vitro spheroids comprised of cancer cells and ECM...
January 5, 2017: Biomacromolecules
Sipei Li, Hee Sung Chung, Antonina Simakova, Zongyu Wang, Sangwoo Park, Liye Fu, Devora Cohen-Karni, Saadyah Averick, Krzysztof Matyjaszewski
The synthesis of a sulfoxide-based water-soluble polymer, poly(2-(methylsulfinyl)ethyl acrylate) (polyMSEA), a polymeric analogue of DMSO, by atom transfer radical polymerization (ATRP) is reported. Well-defined linear polymers were synthesized using relatively low amounts of copper catalyst (1000 or 100 ppm). Two types of star polymers were synthesized by either an "arm-first" approach or a "core-first" approach using a biodegradable β-cyclodextrin core. The glass transition temperatures of both the linear polymer (16 °C) and star polymer (32 °C) were determined by differential scanning calorimetry (DSC)...
January 5, 2017: Biomacromolecules
Yu Zhao, Yufei Zhang, Changchun Wang, Guosong Chen, Ming Jiang
Protection and deprotection are basic procedures in oligosaccharide synthesis. By taking advantage of the processes of attaching and removing the protecting groups, preparation of oligosaccharides with complex structures can be achieved with relatively high yields. However, the role of protecting groups in solution properties and self-assembly of synthetic glycopolymers has been overlooked in the literature. In this paper, we focused on such effects for well-designed copolymers in which different numbers of benzyl (Bn) groups are installed regioselectively in saccharide rings...
January 5, 2017: Biomacromolecules
Bugra Aktan, Laura Chambre, Rana Sanyal, Amitav Sanyal
Mutlifunctionalizable nanogels are fabricated using thermally driven self-assembly and crosslinking of reactive thermoresponsive copolymers. Nanogels thus fabricated can be easily conjugated with various appropriately functionalized small molecules and/or ligands to tailor them for various applications in delivery and imaging. In this study, poly (ethylene glycol) methacrylate based maleimide bearing copolymer was crosslinked with a dithiol-based crosslinker to synthesize nanogels. Due to lower critical solution temperature around 55 oC in aqueous media, these copolymers assemble into nano-sized aggregates when heated to this temperature, and are crosslinked using the thiol-maleimide conjugation...
January 4, 2017: Biomacromolecules
Teruhiko Matsubara, Ryohei Otani, Miki Yamashita, Haruka Maeno, Hanae Nodono, Toshinori Sato
Glycosphingolipids are major components of the membrane raft, and several kinds of viruses and bacterial toxins are known to bind to glycosphingolipids in the membrane raft. Since the viral genes and pathogenic proteins that are taken into cells are directly delivered to their target organelles, caveolae/raft-mediated endocytosis represents a promising pathway for specific delivery. In the present study, we demonstrated the ability of an artificial pentadecapeptide, which binds to ganglioside GM3, to deliver protein into cells by caveolae/raft-mediated endocytosis...
January 4, 2017: Biomacromolecules
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"