keyword
MENU ▼
Read by QxMD icon Read
search

Atomic force microscopy

keyword
https://www.readbyqxmd.com/read/28728087/surface-imprinted-bacterial-cellulose-nanofibers-for-hemoglobin-purification
#1
Monireh Bakhshpour, Emel Tamahkar, Müge Andaç, Adil Denizli
There is a significant need for the development of the novel adsorbents in the field of protein purification. In this study, thin hemoglobin imprinted film (MIP) was fabricated onto the bacterial cellulose nanofibers' (BCNFs) by surface imprinting method using metal ion coordination interactions with N-methacryloyl-(L)-histidinemethylester (MAH) and copper ions. The hemoglobin surface imprinted bacterial cellulose nanofibers (MIP-BCNFs) was applied to selective recognition of hemoglobin and purification from hemolysate...
July 10, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28728044/atomic-force-microscopy-study-of-morphological-modifications-induced-by-different-decontamination-treatments-on-escherichia-coli
#2
Florina Lucica Zorila, Cristina Ionescu, Liviu Stefan Craciun, Bogdan Zorila
In this paper we used atomic force microscopy (AFM) to investigate the surface morphology of Escherichia coli, after being subjected to decontamination treatments, at sub-MICs levels (minimal inhibitory concentrations), with different disinfectants used in hospitals, pharmaceutical, food industry and even in our home, as an essential means to prevent the spreading of microorganisms. This article focuses on different morphological modifications adopted by E. coli cells as responses to the different modes of action of these substances...
July 14, 2017: Ultramicroscopy
https://www.readbyqxmd.com/read/28727920/ballistic-penetration-of-highly-charged-nanoaerosol-particles-through-a-lipid-monolayer
#3
Victor N Morozov, Yuri M Shlyapnikov, Igor L Kanev, Elena Andreevna Shlyapnikova
To be used as a drug, inhaled nanoaerosol particles (NAPs) must first penetrate the lipid layer on top of the lung fluid before they will be able to reach the lung epithelium. We investigated how the penetration of NAPs through a model lipid monolayer (LM) depends upon their charging level and size. It was shown that deposition of NAPs 20-200 nm in diameter and charged to the Rayleigh limit gradually increased the surface tension of a dipalmitoylphosphatidylcholine monolayer (DPPC), indicating a loss of lipid molecules from the monolayer...
July 20, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28726950/one-dna-strand-homo-polymerizes-into-defined-nanostructures
#4
Mo Li, Hua Zuo, Jinwen Yu, Xinfeng Zhao, Chengde Mao
We report a strategy for programmed DNA self-assembly that is favorable in terms of both thermodynamics and kinetics. In a previous study, it has been demonstrated that DNA self-assembly is primarily driven by thermodynamics and the assembly kinetics is not considered. To reach such stable states at equilibria, prolonged annealing duration is needed. In addition, there are cases where the desired structures could not compete with alternative structures. For example, a single-stranded DNA with a palindromic sequence quickly folds into a one-stranded hairpin instead of forming a two-stranded DNA duplex...
July 20, 2017: Nanoscale
https://www.readbyqxmd.com/read/28726942/conjugated-polymer-covalently-modified-graphene-oxide-quantum-dots-for-ternary-electronic-memory-devices
#5
Fei Fan, Bin Zhang, Yaming Cao, Xutong Yang, Junwei Gu, Yu Chen
Zero dimensional graphene oxide (GO) quantum dots (GOQDs) have been expected to play an important role in the development of new memory materials. When the size of GO was reduced to that of GOQDs, both the electron affinity and ionization potential of GO were found to be decreased, and this was followed by the elevation of lowest energy unoccupied molecular orbital (LUMO) energy level. This implies that the electron withdrawing ability of GOQDs is weaker than that of GO. In this work, a novel arylamine-based polyazomethine covalently functionalized graphene oxide quantum dots (TPAPAM-GOQDs), which was synthesized using an amidation reaction, was for the first time used to fabricate a ternary memory device with a configuration of gold/TPAPAM-GOQDs/indium tin oxide...
July 20, 2017: Nanoscale
https://www.readbyqxmd.com/read/28726802/strain-induced-skeletal-rearrangement-of-a-polycyclic-aromatic-hydrocarbon-on-a-copper-surface
#6
Akitoshi Shiotari, Takahiro Nakae, Kota Iwata, Shigeki Mori, Tetsuo Okujima, Hidemitsu Uno, Hiroshi Sakaguchi, Yoshiaki Sugimoto
Controlling the structural deformation of organic molecules can drive unique reactions that cannot be induced only by thermal, optical or electrochemical procedures. However, in conventional organic synthesis, including mechanochemical procedures, it is difficult to control skeletal rearrangement in polycyclic aromatic hydrocarbons (PAHs). Here, we demonstrate a reaction scheme for the skeletal rearrangement of PAHs on a metal surface using high-resolution noncontact atomic force microscopy. By a combination of organic synthesis and on-surface cyclodehydrogenation, we produce a well-designed PAH-diazuleno[1,2,3-cd:1',2',3'-fg]pyrene-adsorbed flatly onto Cu(001), in which two azuleno moieties are highly strained by their mutual proximity...
July 20, 2017: Nature Communications
https://www.readbyqxmd.com/read/28724292/adsorption-of-proteins-on-colloidal-lignin-particles-for-advanced-biomaterials
#7
Timo Leskinen, Joanna Witos, Juan José Valle Delgado, Kalle Sakari Lintinen, Mauri A Kostiainen, Susanne Kristina Wiedmer, Monika Österberg, Maija-Liisa Mattinen
Coating of colloidal lignin particles (CLPs), or lignin nanoparticles (LNPs), with proteins was evaluated in order to establish a safe, self-assembly-mediated modification technique to tune their surface chemistry. Gelatin and poly- L-lysine formed the most pronounced protein corona on the CLP surface, as determined by dynamic light scattering (DLS) and zeta potential measurements. Spherical morphology of individual protein coated CLPs was confirmed by transmission electron (TEM) and atomic force (AFM) microscopy...
July 19, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28723958/can-single-molecule-localization-microscopy-be-used-to-map-closely-spaced-rgd-nanodomains
#8
Mahdie Mollazade, Thibault Tabarin, Philip R Nicovich, Alexander Soeriyadi, Daniel J Nieves, J Justin Gooding, Katharina Gaus
Cells sense and respond to nanoscale variations in the distribution of ligands to adhesion receptors. This makes single molecule localization microscopy (SMLM) an attractive tool to map the distribution of ligands on nanopatterned surfaces. We explore the use of SMLM spatial cluster analysis to detect nanodomains of the cell adhesion-stimulating tripeptide arginine-glycine-aspartic acid (RGD). These domains were formed by the phase separation of block copolymers with controllable spacing on the scale of tens of nanometers...
2017: PloS One
https://www.readbyqxmd.com/read/28723581/the-structure-and-function-of-cell-membranes-studied-by-atomic-force-microscopy
#9
REVIEW
Yan Shi, Mingjun Cai, Lulu Zhou, Hongda Wang
The cell membrane, involved in almost all communications of cells and surrounding matrix, is one of the most complicated components of cells. Lack of suitable methods for the detection of cell membranes in vivo has sparked debates on the biochemical composition and structure of cell membranes over half a century. The development of single molecule techniques, such as AFM, SMFS, and TREC, provides a versatile platform for imaging and manipulating cell membranes in biological relevant environments. Here, we discuss the latest developments in AFM and the progress made in cell membrane research...
July 16, 2017: Seminars in Cell & Developmental Biology
https://www.readbyqxmd.com/read/28723185/silanization-of-sapphire-surfaces-for-optical-sensing-applications
#10
Tanja Sandner, Annina M Steinbach, Peter Knittel, Thomas Diemant, R Jürgen Behm, Steffen Strehle, Christine Kranz, Boris Mizaikoff
Well-characterized silane layers are essential for optimized attachment of (bio)molecules enabling reliable chem/biosensor performance. Herein, binding properties and orientation of 3-mercaptopropyltrimethoxysilane layers at crystalline sapphire (0001) surfaces were determined by water contact angle measurements, infrared reflection absorption spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. Infrared reflection absorption spectroscopy measurements suggest an almost perpendicular arrangement of the MPTMS molecules to the substrate surface...
April 28, 2017: ACS Sensors
https://www.readbyqxmd.com/read/28722393/multiligand-metal-phenolic-assembly-from-green-tea-infusions
#11
Md Arifur Rahim, Mattias Björnmalm, Nadja Bertleff-Zieschang, Yi Ju, Srinivas Mettu, Michael G Leeming, Frank Caruso
The synthesis of hybrid functional materials using the coordination-driven assembly of metal-phenolic networks (MPNs) is of interest in diverse areas of materials science. To date, MPN assembly has been explored as monoligand systems (i.e., containing a single type of phenolic ligand) where the phenolic components are primarily obtained from natural sources via extraction, isolation, and purification processes. Herein, we demonstrate the fabrication of MPNs from a readily available, crude phenolic source-green tea (GT) infusions...
July 19, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28721722/pillar-5-arene-based-supramolecular-plasmonic-thin-films-for-label-free-quantitative-and-multiplex-sers-detection
#12
Verónica Montes García, Borja Gómez-González, Diego M Solís, Jose M Taboada, Norman Jiménez Otero, Jacobo de Uña-Álvarez, Fernando Obelleiro, Luis García-Río, Jorge Perez-Juste, Isabel Pastoriza-Santos
Novel plasmonic thin films based on electrostatic layer-by-layer (LbL) deposition of citrate-stabilized Au nanoparticles (NPs) and ammonium pillar[5]arene (AP[5]A) has been developed. The supramolecular-induced LbL assembly of the plasmonic nanoparticles yields to the formation of controlled hot-spots with uniform interparticle distances. At the same time this strategy allows to modulate the density and dimensions of the Au aggregates, and therefore the optical response, on the thin film with the number of AuNP-AP[5]A deposition cycles...
July 19, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28721420/adsorption-of-galloyl-catechin-aggregates-significantly-modulates-membrane-mechanics-in-the-absence-of-biochemical-cues
#13
Takahisa Matsuzaki, Hiroaki Ito, Veronika Chevyreva, Ali Makky, Stefan Kaufmann, Kazuki Okano, Naritaka Kobayashi, Masami Suganuma, Seiichiro Nakabayashi, Hiroshi Y Yoshikawa, Motomu Tanaka
Physical interactions of four major green tea catechin derivatives with cell membrane models were systemically investigated. Catechins with the galloyl moiety caused the aggregation of small unilamellar vesicles and an increase in the surface pressure of lipid monolayers, while those without did not. Differential scanning calorimetry revealed that, in a low concentration regime (≤10 μM), catechin molecules are not significantly incorporated into the hydrophobic core of lipid membranes as substitutional impurities...
July 19, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28719862/green-biosynthesis-of-silver-nanoparticles-using-leaves-extract-of-artemisia-vulgaris-and-their-potential-biomedical-applications
#14
Tahir Rasheed, Muhammad Bilal, Hafiz M N Iqbal, Chuanlong Li
Biosynthesis of nanoparticles from plant extracts is receiving enormous interest due to their abundant availability and a broad spectrum of bioactive reducing metabolites. In this study, the reducing potential of Artemisia vulgaris leaves extract (AVLE) was investigated for synthesizing silver nanoparticles without the addition of any external reducing or capping agent. The appearance of blackish brown color evidenced the complete synthesis of nanoparticles. The synthesized silver nanoparticles were characterized by UV-vis spectroscopy, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), atomic force microscopy (AFM) and Fourier transforms infrared spectroscopy (FT-IR) analysis...
July 8, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28719860/liposome-modified-titanium-surface-a-strategy-to-locally-deliver-bioactive-molecules
#15
Vincenzo De Leo, Monica Mattioli-Belmonte, Maria Teresa Cimmarusti, Annamaria Panniello, Manuela Dicarlo, Francesco Milano, Angela Agostiano, Elvira De Giglio, Lucia Catucci
Titanium and its alloys are widely employed materials for implants in orthopedic or dental surgery due to their mechanical properties, resistance to corrosion and osseointegration capability. However adverse reactions at the tissue/implant interface may occur, which limit the success of the osseointegration process. Therefore, different strategies have to be used to overcome these drawbacks. In this work, we developed two different liposome-based coatings on titanium surfaces as drug or bioactive molecule deposits for dental/orthopedic implant applications...
July 8, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28719858/interfacial-analysis-of-sirna-complexes-with-poly-ethylenimine-pei-or-pamam-dendrimers-in-gene-delivery
#16
Patrick K C Chang, Clive A Prestidge, Kristen E Bremmell
Solution and interfacial analysis has been employed to gain insight into the complexation of siRNA using either G4 PAMAM dendrimers or 25kDa branched poly-ethylenimine (bPEI). The size, charge and shape/structure of the complexing agents were probed using atomic force microscopy (AFM), circular dichroism spectrometry (CD), dynamic light scattering (DLS), and gel electrophoresis (GE). The binding capability of these cationic polymers to the siRNA molecule, subsequently controls the surface/adsorption behaviour of the complexes to a negatively charged surface...
July 8, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28719744/high-resolution-insights-into-the-stepwise-self-assembly-of-nanofiber-from-bioactive-peptides
#17
Fude Sun, Long Chen, Xiufang Ding, Lida Xu, Xirui Zhou, Peng Wei, Jun-Feng Liang, Shi-Zhong Luo
Peptide self-assembly has a profound biological significance since self-assembled bioactive peptides are gifted with improved bioactivity as well as life-span. In this study, peptide self-assembly was investigated using a therapeutic peptide, PTP-7S (EENFLGALFKALSKLL). Combining experiments of atomic force microscopy (AFM), circular dichroism (CD) and 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence spectra, PTP-7S showing α-helix was found self-assembling into nanofibers in solution. Relying on the coarse-grained (CG) dynamic simulations, the self-assembling of PTP-7S was revealed as a stepwise process that peptide monomers first clustered into peptide-assembling units (PUs) with charged surface, and then the PUs integrated together to construct nano-fibril aggregates...
July 18, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28719741/macroscopic-strain-induced-transition-from-quasi-infinite-gold-nanoparticle-chains-to-defined-plasmonic-oligomers
#18
Anja Maria Steiner, Martin Mayer, Maximilian Seuss, Svetoslav Nikolov, Kenneth D Harris, Alexander Alexeev, Christian Kuttner, Tobias A F Koenig, Andreas Fery
We investigate the formation of chains of few plasmonic nanoparticles - so called plasmonic oligomers - by strain induced fragmentation of linear particle assemblies. Detailed investigations of the fragmentation process are conducted by in-situ atomic force microscopy (AFM) and UV-vis-NIR spectroscopy. Based on these experimental results and mechanical simulations computed by the lattice spring model (LSM), we propose a formation mechanism which explains the observed decrease of chain polydispersity upon increasing strain and provides experimental guidelines for tailoring chain length distribution...
July 18, 2017: ACS Nano
https://www.readbyqxmd.com/read/28719211/real-space-demonstration-of-induced-crystalline-3d-nanostructuration-of-organic-layers
#19
Markos Paradinas, Ana Pérez-Rodríguez, Esther Barrena, Carmen Ocal
The controlled 3D nanostructuration of molecular layers of the semiconducting molecules C22H14 (pentacene) and N, N'-dioctyl-3, 4, 9, 10-perylenetetracarboxylicdiimide (PTCDI-C8) is addressed. A tip-assisted method based using atomic force microscopy (AFM) is developed for removing the organic material and relocating it in up to five layers thick nanostructures. Moreover, unconventional molecular scale imaging combining diverse friction force microscopy modes reveals the stacking sequence of the piled layers...
July 18, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28719187/exploring-the-role-of-habitat-on-the-wettability-of-cicada-wings
#20
Junho Oh, Catherine Dana, Sungmin Hong, Jessica K Roman, Kyoo D Jo, Je W Hong, Jonah Nguyen, Donald M Cropek, Marianne Alleyne, Nenad Miljkovic
Evolutionary pressure has pushed the wings of many insect species to develop micro/nanostructures that can significantly affect wettability and enable functionalities such as droplet jumping, self-cleaning, anti-fogging, anti-microbial, and anti-reflectivity. Significant effort is underway to understand the wing surface structure to establish rational design tools for the development of novel engineered materials. Most studies, however, have focused on superhydrophobic wings obtained from a single insect species, in particular, the Psaltoda claripennis cicada...
July 18, 2017: ACS Applied Materials & Interfaces
keyword
keyword
63989
1
2
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"