Read by QxMD icon Read

Biomedical chemistry

Wing-Fu Lai, Andrey L Rogach, Wing-Tak Wong
Cyclodextrins (CDs) are naturally occurring cyclic oligosaccharides bearing a basket-shaped topology with an "inner-outer" amphiphilic character. The abundance of hydroxyl groups enables CDs to be functionalized with multiple targeting ligands and imaging elements. The imaging time, and the payload of different imaging elements, can be tuned by taking advantage of the commercial availability of CDs with different sizes of the cavity. This review aims to offer an outlook of the chemistry and engineering of CDs for the development of molecular probes...
September 20, 2017: Chemical Society Reviews
Paola Taddei, Michele Di Foggia, Simona Martinotti, Elia Ranzato, Irene Carmagnola, Valeria Chiono, Masuhiro Tsukada
Silk fibroin may be chemically modified by grafting, with the purpose of improving its properties according to the desired function. In this study, silk fabrics from Bombyx mori silk fibres were grafted with 2-hydroxyethyl methacrylate (HEMA), as well as a binary mixture of HEMA and 4-hydroxybutyl acrylate (HBA). The samples were then electrospun from trifluoroacetic acid and treated with aqueous methanol. The % weight gains ascribable to HEMA and HBA were successfully determined through Raman spectroscopy...
September 16, 2017: International Journal of Biological Macromolecules
Ding-Ping Bai, Xi-Feng Zhang, Guo-Liang Zhang, Yi-Fan Huang, Sangiliyandi Gurunathan
BACKGROUND: Zinc oxide nanoparticles (ZnO NPs) are frequently used in industrial products such as paint, surface coating, and cosmetics, and recently, they have been explored in biologic and biomedical applications. Therefore, this study was undertaken to investigate the effect of ZnO NPs on cytotoxicity, apoptosis, and autophagy in human ovarian cancer cells (SKOV3). METHODS: ZnO NPs with a crystalline size of 20 nm were characterized with various analytical techniques, including ultraviolet-visible spectroscopy, X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and atomic force microscopy...
2017: International Journal of Nanomedicine
Daiana K Deda, Roberta M Cardoso, Mayara K Uchiyama, Christiane Pavani, Sergio H Toma, Mauricio S Baptista, Koiti Araki
Size, shape, and surface properties of superparamagnetic iron oxide nanoparticles (SPIONs) can influence their interaction with biological systems, particularly the incorporation by tumor cells and consequently the biological activity and efficiency in biomedical applications. Several strategies have been used to evaluate cellular uptake of SPIONs. While qualitative methods are generally based on microscopy techniques, quantitative assays are carried out by techniques such as inductively coupled plasma-mass spectrometry and flow cytometry...
September 16, 2017: Analytical and Bioanalytical Chemistry
R Jayakumar, S Meenakshi
No abstract text is available yet for this article.
November 2017: International Journal of Biological Macromolecules
Jason M Haber, Konstantin Sokolov
Citrate-stabilized silver nanoprisms (AgNPrs) can be easily functionalized using well-developed thiol based surface chemistry that is an important requirement for biosensor applications utilizing localized surface plasmon resonance (LSPR) and surface-enhanced Raman Scattering (SERS). Unfortunately, currently available protocols for synthesis of citrate-coated AgNPrs do not produce stable nanoparticles thus limiting their usefulness in biosensing applications. Here we address this problem by carrying out a systematic study of citrate-stabilized, peroxide-based synthesis of AgNPrs to optimize reaction conditions for production of stable and reproducible nanoprisms...
September 12, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
M Canillas, E Chinarro, A P Pêgo, B Moreno
TiO2 is able to scavenge reactive oxygen and nitrogen species (ROS and RNS) in the absence of light. The scavenging mechanism has been related to the chemistry of defects (oxygen vacancy reduced oxidation states of Ti) but it is still unknown. This study describes the ROS scavenging activity of different titanium oxide phases and relates their scavenging activities with the Ti(4+)/Ti(3+) molar ratio as well as the band gap value. The Ti5O9 phase, with a mixture of both oxidation states, presented a substantially higher percentage of 2,2-diphenyl-1-picrylhydracyl radicals (DPPH˙) eliminated per m(2) of specific surface area in comparison to phases with predominant oxidation states Ti(4+) or Ti(3+) such as TiO2 and Ti2O3, respectively...
September 12, 2017: Chemical Communications: Chem Comm
D Vilela, A C Hortelao, R Balderas-Xicohténcatl, M Hirscher, K Hahn, X Ma, S Sánchez
Self-propelled micro/nano-devices have been proved as powerful tools in various applications given their capability of both autonomous motion and on-demand task fulfilment. Tubular micro-jets stand out as an important member in the family of self-propelled micro/nano-devices and are widely explored with respect to their fabrication and functionalization. A few methods are currently available for the fabrication of tubular micro-jets, nevertheless there is still a demand to explore the fabrication of tubular micro-jets made of versatile materials and with the capability of multi-functionalization...
September 11, 2017: Nanoscale
Ruming Jiang, Han Liu, Meiying Liu, Jianwen Tian, Qiang Huang, Hongye Huang, Yuanqing Wen, Qian-Yong Cao, Xiaoyong Zhang, Yen Wei
Multicomponent reactions (MCRs) have recently attracted great attention as one of the most important tools for the construction of various organic compounds in modern organic chemistry. In this work, we introduced an efficient one-pot strategy to successfully fabricate the fluorescent polymeric nanoparticles (FPNs) with aggregation-induced emission (AIE) characteristic via the conjugation of hyperbranched polyamino compound polyethyleneimine (PEI), AIE dye (named as PhE-OH) and paraformaldehyde (PF) through a Mannich reaction...
December 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Peng Zhao, Justin George, Bin Li, Nooshin Amini, Janet Paluh, Jun Wang
We report a novel strategy for fabrication of multifunctional dumbbell particles (DPs) through click chemistry for monitoring single-cell cytokine releasing. Two different types of DPs were prepared on a large scale through covalent bioorthogonal reaction between methyltetrazine and trans-cyclooctene on a microchip under a magnetic field. After collection of the DPs, the two sides of each particle were further functionalized with different antibodies for cell capturing and cytokine detection, respectively. These DPs labeled with different fluorescent dyes have been used for multiplex detection and analysis of cytokines secreted by single live cells...
September 18, 2017: ACS Applied Materials & Interfaces
Mark P Hendricks, Kohei Sato, Liam C Palmer, Samuel I Stupp
Peptide amphiphiles (PAs) are small molecules that contain hydrophobic components covalently conjugated to peptides. In this Account, we describe recent advances involving PAs that consist of a short peptide sequence linked to an aliphatic tail. The peptide sequence can be designed to form β-sheets among the amino acids near the alkyl tail, while the residues farthest from the tail are charged to promote solubility and in some cases contain a bioactive sequence. In water, β-sheet formation and hydrophobic collapse of the aliphatic tails induce assembly of the molecules into supramolecular one-dimensional nanostructures, commonly high-aspect-ratio cylindrical or ribbonlike nanofibers...
September 6, 2017: Accounts of Chemical Research
Yingge Shi, Guanjian Zeng, Dazhuang Xu, Meiying Liu, Ke Wang, Zhen Li, Lihua Fu, Qingsong Zhang, Xiaoyong Zhang, Yen Wei
Carbon nanotubes (CNTs) are a type of one-dimensional carbon nanomaterials that possess excellent physicochemical properties and have been potentially utilized for a variety of applications. Surface modification of CNTs with polymers is a general route to expand and improve the performance of CNTs and has attracted great research interest over the past few decades. Although many methods have been developed previously, most of these methods still showed some disadvantages, such as low efficiency, complex experimental procedure and harsh reaction conditions etc...
November 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Bhupinder Singh, Rajneet Kaur Khurana, Babita Garg, Sumant Saini, Ranjot Kaur
With the advent of "intelligent" polymeric systems, the use of stimuli-responsive in situ gelling systems has been revolutionized. These interesting polymers exist as free-flowing aqueous solutions before administration and undergo a phase transition to form a viscoelastic gel in a physiological environ through various stimuli such as temperature, pH, solvent, biochemical, magnetic, electric, ultrasound, and photo-polymerization. These smart polymers are endowed with numerous merits such as ease of administration, sustained release, reduced frequent administration with improved patient compliance, and targeted and spatial delivery of a drug with reduced frequency of side effects...
2017: Critical Reviews in Therapeutic Drug Carrier Systems
Hyejoong Jeong, Jangsun Hwang, Hwankyu Lee, Paula T Hammond, Jonghoon Choi, Jinkee Hong
Biocompatible polymers have been extensively applied to molecular assembly techniques on a micro- and nanoscale to miniaturize functional devices for biomedical uses. However, cytotoxic assessments of developed devices are prone to partially focus on non-specific cells or cells associated with the specific applications. Thereby, since toxicity is dependent on the type of cells and protocols, we do not fully understand the relative toxicities of polymers. Additionally, we need to ensure the blood cell biocompatibility of developed devices prior to that of targeted cells because most of the devices contact the blood before reaching the targeted regions...
August 25, 2017: Scientific Reports
Matin Mahmoudifard, Masoud Soleimani, Manuchehr Vossoughi
The surface of polyacrylonitrile electrospun nanofibrous membrane (PAN NFM) was aminated by the ammonia plasma treatment. The content of amine groups has been estimated for different time of plasma treatment. The newly generated amine groups were successfully activated by glutaraldehyde (Ga) for the covalent attachment of the protein molecules on the NFM surface. Bio-functionalization of ammonia plasma treated PAN NFM was carried out by the primary antibodies (Ab) immobilization as a protein model through Ga coupling chemistry...
August 25, 2017: Scientific Reports
Bryony Elbert, Alistair Farley, Timothy Gorman, Tarn Johnson, Christophe Genicot, Benedicte Lallemand, Patrick Pasau, Jakub Flasz, Jose Castro, Malcolm Maccoss, Robert Paton, Christopher Schofield, Martin Smith, Michael Willis, Darren James Dixon
Heteroaromatic nitriles are important compounds in drug discovery, both for their prevalence in the clinic and due to the diverse range of transformations they can undergo. As such, efficient and reliable methods to access them have the potential for far-reaching impact across synthetic chemistry and the biomedical sciences. Here we report an approach to heteroaromatic C-H cyanation through triflic anhydride activation, nucleophilic addition of cyanide, and concomitant elimination of trifluoromethanesulfinate to regenerate the cyanated heteroaromatic ring...
August 23, 2017: Chemistry: a European Journal
Anees A Ansari
Monoclinic-type tetragonal LaPO4 :Eu (core) and LaPO4 :Eu@LaPO4 (core/shell) nanorods (NRs) were successfully prepared using a urea-based co-precipitation process under ambient conditions. An amorphous silica layer was coated around the luminescent core/shell NRs via the sol-gel process to improve their solubility and colloidal stability in aqueous and non-aqueous media. The prepared nano-products were systematically characterized by X-ray diffraction pattern, transmission electron microscopy, energy dispersive X-ray analysis, and FTIR, UV/Vis, and photoluminescence spectroscopy to examine their phase purity, crystal phase, surface chemistry, solubility and luminescence characteristics...
August 17, 2017: Luminescence: the Journal of Biological and Chemical Luminescence
Adina Badea, Joselle M McCracken, Emily G Tillmaand, Mikhail E Kandel, Aaron W Oraham, Molly B Mevis, Stanislav S Rubakhin, Gabriel Popescu, Jonathan V Sweedler, Ralph G Nuzzo
Understanding and controlling the interactions occurring between cells and engineered materials are central challenges toward progress in the development of biomedical devices. In this work, we describe materials for direct ink writing (DIW), an extrusion-based type of 3D printing, that embed a custom synthetic protein (RGD-PDL) within the microfilaments of 3D-hydrogel scaffolds to modify these interactions and differentially direct tissue-level organization of complex cell populations in vitro. The RGD-PDL is synthesized by modifying poly-d-lysine (PDL) to varying extents with peptides containing the integrin-binding motif Arg-Gly-Asp (RGD)...
September 13, 2017: ACS Applied Materials & Interfaces
Fatemeh Karimi, Joe Collins, Daniel E Heath, Luke A Connal
A dual-responsive, cell capture and release surface was prepared through the incorporation of phenylboronic acid (PBA) groups into an oxime-based polyethylene glycol (PEG) hydrogel. Owing to its PEG-like properties, the unfunctionalized hydrogel was nonfouling. The use of highly efficient oxime chemistry allows the incorporation of commercially available 3,5-diformylphenyl boronic acid into the hydrogel matrix. Thus, the surface properties of the hydrogel were modified to enable reversible cell capture and release...
August 22, 2017: Bioconjugate Chemistry
Hope Adamson, Alan M Bond, Alison Parkin
Biological electron-exchange reactions are fundamental to life on earth. Redox reactions underpin respiration, photosynthesis, molecular biosynthesis, cell signalling and protein folding. Chemical, biomedical and future energy technology developments are also inspired by these natural electron transfer processes. Further developments in techniques and data analysis are required to gain a deeper understanding of the redox biochemistry processes that power Nature. This review outlines the new insights gained from developing Fourier transformed ac voltammetry as a tool for protein film electrochemistry...
August 14, 2017: Chemical Communications: Chem Comm
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"