Self-assembly of clay nanotubes on hair surface for medical and cosmetic formulations

© The Royal Society of Chemistry. While most hair care formulations are developed on the basis of surfactants or polymers, we introduce self-assembly coating of micro and nanoparticles as the underlying principle for hair modification, protection and enhancement. Halloysite clay nanotubes formed by rolled sheets of aluminosilicate kaolin assemble on the surface of hair forming a robust multilayer coverage. Prior to the application, clay nanotubes were loaded with selected dyes or drug allowing for hair coloring or medical treatment. This facile process is based on a 3-minute application of 1 wt% aqueous dispersion of color/drug loaded halloysite resulting in a ca. 3 μm thick uniform hair surface coating. This technique, which employs a very safe, biocompatible and inexpensive material, is ubiquitous with respect to the species of source of hair and additives in solvent, making it viable as an excipient for conventional medical and veterinarian formulations

Nematode epicuticle nanoscale morphology: insights from atomic force microscopy

Here we report on imaging and nanomechanical characterisation of microscopic nematodes epicuticle using atomic force microscopy.This study was supported by Russian Science Foundation grant No 14-14-00924 and performed according to the Russian Government Program of Competitive Growth of Kazan Federal University

Toxicity of halloysite clay nanotubes in vivo: A Caenorhabditis elegans study

© The Royal Society of Chemistry 2015. Here we investigated the toxicity of halloysite clay nanotubes in vivo employing a Caenorhabditis elegans nematode as a model organism. Using enhanced dark-field microscopy and physiological tests, we found that halloysite is localised exclusively in the alimentary system and does not induce severe toxic effects on nematodes

Nano-labelled cells - A functional tool in biomedical applications

© 2014 Elsevier Ltd. All right reserved. Nanotechnology offers an unprecedented number of opportunities for biomedical research, utilizing the unusual functionalities of nanosized materials. Here we describe the recent advances in fabrication and utilization of nanoparticle-labelled cells. We present a brief overview of the most promising techniques, namely layer-by-layer polyelectrolyte assembly on cells and intracellular and extracellular labelling with magnetic nanoparticles. Several important practical application of nanofucntionalized cells, including tissue engineering and tumour therapy, are reviewed

Nanoscale imaging and characterization of Caenorhabditis elegans epicuticle using atomic force microscopy

© 2016 Elsevier Inc.Here we introduce PeakForce Tapping non-resonance atomic force microscopy for imaging and nanomechanical mapping of Caenorhabditis elegans nematodes. The animals were imaged both in air and water at nanoscale resolution. Layer-by-layer glass surface modification was employed to secure the worms for imaging in water. Microtopography of head region, annuli, furrows, lateral alae and tail region was visualized. Analysis of nanoscale surface features obtained during AFM imaging of three larval and adult hermaphrodite nematodes in natural environment allowed for numerical evaluation of annuli periodicity, furrows depth and annuli roughness. Nanomechanical mapping of surface deformation, Young modulus and adhesion confirms that the mechanical properties of the nematode cuticle are non-uniform. Overall, PeakForce Tapping AFM is a robust and simple approach applicable for nanoscale three-dimensional imaging and characterization of C. elegans nematodes

Silver nanoparticle-coated "cyborg" microorganisms: Rapid assembly of polymer-stabilised nanoparticles on microbial cells

© The Royal Society of Chemistry. Fabrication of "cyborg" cells (biological cells with surfaces functionalised using a variety of nanomaterials) has become a fascinating area in cell surface engineering. Here we report a simple procedure for fabrication of polycation-stabilised 50 nm silver nanoparticles and application of these nanoparticles for fabrication of viable "cyborg" microbial cells (yeast and bacteria). Cationic polymer-stabilised nanoparticles electrostatically adhere to microbial cells producing an even monolayer on the cell walls, as demonstrated using enhanced dark-field microscopy, atomic force microscopy and microelectrophoresis. Our procedure is exceptionally fast, being completed within 20 min after introduction of cells into nanoparticle aqueous suspensions. Polymer-stabilised silver nanoparticles are highly biocompatible, with viability rates reaching 97%. We utilised "cyborg" cells built using bacteria and silver nanoparticles to deliver nanoparticles into C. elegans microworms. We believe that the technique described here will find numerous applications in cell surface engineering. This journal i

Nanomodified Bacteria Alcanivorax Borkumensis as an Indicator of Carbohydrates in Sea Water

The work was supported by the Russian Foundation for Basic Research (grant № 18-34-00778), by Program of Competitive Growth of KFU and funded by Russian presidential grant (MK-4498.2018.4)

Dark-field/hyperspectral microscopy for detecting nanoscale particles in environmental nanotoxicology research

Nanoscale contaminants (including engineered nanoparticles and nanoplastics) pose a significant threat to organisms and environment. Rapid and non-destructive detection and identification of nanosized materials in cells, tissues and organisms is still challenging, although a number of conventional methods exist. These approaches for nanoparticles imaging and characterisation both inside the cytoplasm and on the cell or tissue outer surfaces, such as electron or scanning probe microscopies, are unquestionably potent tools, having excellent resolution and supplemented with chemical analysis capabilities. However, imaging and detection of nanomaterials in situ, in wet unfixed and even live samples, such as living isolated cells, microorganisms, protozoans and miniature invertebrates using electron microscopy is practically impossible, because of the elaborate sample preparation requiring chemical fixation, contrast staining, matrix embedding and exposure into vacuum. Atomic force microscopy, in several cases, can be used for imaging and mechanical analysis of live cells and organisms under ambient conditions, however this technique allows for investigation of surfaces. Therefore, a different approach allowing for imaging and differentiation of nanoscale particles in wet samples is required. Dark-field microscopy as an optical microscopy technique has been popular among researchers, mostly for imaging relatively large specimens. In recent years, the so-called “enhanced dark field” microscopy based on using higher numerical aperture light condensers and variable numerical aperture objectives has emegred, which allows for imaging of nanoscale particles (starting from 5 nm nanospheres) using almost conventional optical microscopy methodology. Hyperspectral imaging can turn a dark-field optical microscope into a powerful chemical characterisation tool. As a result, this technique is becoming popular in environmental nanotoxicology studies. In this Review Article we introduce the reader into the methodology of enhanced dark-field and dark-field-based hyperspectral microscopy, covering the most important advances in this rapidly-expanding area of environmental nanotoxicology

Toxicity of halloysite clay nanotubes in vivo: A Caenorhabditis elegans study

© The Royal Society of Chemistry 2015. Here we investigated the toxicity of halloysite clay nanotubes in vivo employing a Caenorhabditis elegans nematode as a model organism. Using enhanced dark-field microscopy and physiological tests, we found that halloysite is localised exclusively in the alimentary system and does not induce severe toxic effects on nematodes

Toxicity of halloysite clay nanotubes in vivo: A Caenorhabditis elegans study

© The Royal Society of Chemistry 2015. Here we investigated the toxicity of halloysite clay nanotubes in vivo employing a Caenorhabditis elegans nematode as a model organism. Using enhanced dark-field microscopy and physiological tests, we found that halloysite is localised exclusively in the alimentary system and does not induce severe toxic effects on nematodes