Tag Archives: Louisiana Tech University

Nanoparticles for prolonged anti-lice protection

Caption Graphical abstract [the animal is a capybara, world’s largest rodent] Credit: Kazan Federal University, Louisiana Tech University, Gubkin University

A September 28, 2021Kazan Federal University (Russia) press release (also on EurekAlert; Source text: Larisa Busil Photo: Rawil Fakhrullin) announces news that could lead to relief for anyone who owns animals,

An international researcher team of Louisiana Tech University, Gubkin University [also known as, Gubkin Russian State University of Oil and Gas] and Kazan Federal University reported the fabrication of nanoscale insecticidal hair coating for prolonged anti-lice protection. The study was supported by the Russian Science Foundation.

“Treating agricultural and domestic animals infected with ectoparasites (such as lice, fleas, chewing lice, etc.) is among the primary challenges of veterinary medicine and agriculture. In case of mass infestation, regular measures, such as isolation of infected animals or repeated reapplication of insecticides, are not always effective. These methods are time-limited and provide a short-term therapeutic effect,” explains co-author Rawil Fakhrullin, Head of Kazan University’s Bionanotechnology Lab. “Using an inorganic nanoscale carrier as a component of a therapeutic formulation for topical application of insecticides might be the optimal way to address this challenge.”

Halloysite, a natural nanosized tubular mineral, was used as a drug carrier capable of forming a durable and uniform coating on the surface of animal hair.

“Loading an insecticidal drug, permethrin, into halloysite nanotubes reduces the release rate, leading to fewer re-treatments and fewer side effects,” continues Dr. Fakhrullin.

The paper shows that after goat hair samples were treated with halloysite-based nanocontainers, a stable 2-3 micron waterproof coating was formed on the surface of the hair, suitable for long-term antiparasitic protection.

“Long-term insecticidal activity is the result of the gradual release of the drug from the nanotubes. A formulation based on halloysite retains its protective antiparasitic properties after washing the animal’s hair with water. This stable and water-resistant composite coating provides a drug dose effective for long-term protection of animals,” says the interviewee.

The authors also examined the hair structure of the capybara, world’s largest rodent native to South America. They found that the wax-like layer present on the hair surface of this semi-aquatic animal facilitates the formation of a denser and more durable coating of halloysite than in terrestrial animals (guinea pigs and goats). The wax helps retaining nanoclay particles on the surface of the animal’s hair.

Dr. Fakhrullin comments about the test subjects, “We studied the suppressive effects of nanocontainers on goat ectoparasites Damalinia caprae from the Trichodectidae family. At the same time, our technique can be effective towards other types of lice, since these parasites live in hair and maintain close contact with hair cuticles, regardless of the animal’s dietary preferences. We believe that this approach can be used for long-term and sustainable antiparasitic protection of farm animals, especially if other insecticidal preparations are encapsulated in addition to permethrin. In addition, similar drugs can be used for the prevention or treatment of head lice in humans.”

Furthermore, the described material can also be helpful in treating fur in zoological collections.

Here’s a link to and a citation for the paper,

Clay Nanotube Immobilization on Animal Hair for Sustained Anti-Lice Protection by Naureen Rahman, Faith Hannah Scott, Yuri Lvov, Anna Stavitskaya, Farida Akhatova, Svetlana Konnova, Gӧlnur Fakhrullina and Rawil Fakhrullin. Pharmaceutics 2021, 13(9), 1477; DOI: https://doi.org/10.3390/pharmaceutics13091477 Published: 15 September 2021

This paper is open access.

‘Smart dress’ for oil-degrading bacteria (marine oil spill remediation)

This July 22, 2016 news item (on Nanowerk) about bacteria and marine oil spill remediation was a little challenging (for me) to read (Note: A link has been removed),

Bionanotechnology research is targeted on functional structures synergistically combining macromolecules, cells, or multicellular assemblies with a wide range of nanomaterials. Providing micrometer-sized cells with tiny nanodevices expands the uses of the cultured microorganisms and requires nanoassembly on individual live cells (“Nanoshell Assembly for Magnet-Responsive Oil-Degrading Bacteria”).

Surface engineering functionalizes the cell walls with polymer layers and/or nanosized particles and has been widely employed to modify the intrinsic properties of microbial cells. Cell encapsulation allows fabricating live microbial cells with magnetic nanoparticles onto cell walls, which mimics natural magnetotactic bacteria.

For this study researchers from Kazan Federal University and Louisiana Tech University chose Alcanivorax borkumensis marine bacteria as a target microorganism for cell surface engineering with magnetic nanoparticles for the following reasons: (1) these hydrocarbon-degrading bacteria are regarded as an important tool in marine oil spill remediation and potentially can be used in industrial oil-processing bioreactors, therefore the external magnetic manipulations with these cells seems to be practically relevant; (2) A. borkumensis are marine Gram-negative species having relatively fragile and thin cell walls, which makes cell wall engineering of these bacteria particularly challenging.

Rendering oil-degrading bacteria with artificially added magnetic functionality is important to attenuate their properties and to expand their practical use.

[downloaded from http://pubs.acs.org/doi/abs/10.1021/acs.langmuir.6b01743]

[downloaded from http://pubs.acs.org/doi/abs/10.1021/acs.langmuir.6b01743]

A July 22, 2016 Kazan Federal University (Russia) press release (also on EurekAlert), which originated the news item, has more detail about the research,

Cell surface engineering was performed using polycation-coated magnetic nanoparticles, which is a fast and straightforward process utilizing the direct deposition of positively charged iron oxide nanoparticles onto microbial cells during a brief incubation in excessive concentrations of nanoparticles. Gram-negative bacteria cell walls are built from the thin peptidoglycan layer sandwiched between the outer membrane and inner plasma membrane, with lipopolysaccharides rendering the overall negative cell charge, therefore cationic particles will attach to the cell walls due to electrostatic interactions.

Rod-like 0.5-μm diameter Gram-negative bacteria A. borkumensis were coated with 70?100 nm [sic] magnetite shells. The deposition of nanoparticles was performed with extreme care to ensure the survival of magnetized cells.

The development of biofilms on hydrophobic surface is a very important feature of A. borkumensis cells because this is how these cells attach to the oil droplets in natural environments. Consequently, any cell surface modification should not reduce their ability to attach and proliferate as biofilms. Here, at all concentrations of PAH- magnetite nanoparticles investigated, authors of the study detected the similar biofilm growth patterns. Overall, the magnetized cells were able to proliferate and exhibited normal physiological activity.

The next generations of the bacteria have a tendency to remove the artificial shell returning to the native form. Such magnetic nanoencapsulation may be used for the A. borkumensis transportation in the bioreactors to enhance the spill oil decomposition at certain locations.

If I read this rightly, the idea, in future iterations of this research, is to destroy the oil once it’s been gathered by the biofilm. This seems a different approach where other oil spill remediation techniques have hydrophobic/oleophilic sponges absorbing the oil, which could potentially be used in the future. There are carbon nanotube sponges (my April 17, 2012 posting) and boron nitride sponges (my Dec. 7, 2015 posting).

Here’s a link to and a citation for the paper,

Nanoshell Assembly for Magnet-Responsive Oil-Degrading Bacteria by Svetlana A. Konnova, Yuri M. Lvov, and Rawil F. Fakhrullin. Langmuir, Article ASAP DOI: 10.1021/acs.langmuir.6b01743 Publication Date (Web): June 09, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

Self-assembling copper and physiology

An Aug. 24, 2015 news item on Nanowerk highlights work at Louisiana Tech University (US) on self-assembling copper nanocomposites in liquid form,

Faculty at Louisiana Tech University have discovered, for the first time, a new nanocomposite formed by the self-assembly of copper and a biological component that occurs under physiological conditions, which are similar those found in the human body and could be used in targeted drug delivery for fighting diseases such as cancer.

The team, led by Dr. Mark DeCoster, the James E. Wyche III Endowed Associate Professor in Biomedical Engineering at Louisiana Tech, has also discovered a way for this synthesis to be carried out in liquid form. This would allow for controlling the scale of the synthesis up or down, and to grow structures with larger features, so they can be observed.

An Aug. 24, 2015 Louisiana Tech University news release by Dave Guerin, which originated the news item, describes possible future  applications and the lead researcher’s startup company,

“We are currently investigating how this new material interacts with cells,” said DeCoster. “It may be used, for example for drug delivery, which could be used in theory for fighting diseases such as cancer. Also, as a result of the copper component that we used, there could be some interesting electronics, energy, or optics applications that could impact consumer products. In addition, copper has some interesting and useful antimicrobial features.

“Finally, as the recent environmental spill of mining waste into river systems showed us, metals, including copper, can sometimes make their way into freshwater systems, so our newly discovered metal-composite methods could provide a way to “bind up” unwanted copper into a useful or more stable form.”

DeCoster said there were two aspects of this discovery that surprised him and his research team. First, they found that once formed, these copper nanocomposites were incredibly stable both in liquid or dried form, and remained stable for years. “We have been carrying out this research for at least four years and have a number of samples that are at least two years old and still stable,” DeCoster said.

Second, DeCoster’s group was very surprised that these composites are resistant to agglomeration, which is the process by which material clumps or sticks together.

“This is of benefit because it allows us to work with individual structures in order to separate or modify them chemically,” explains DeCoster. “When materials stick together and clump, as many do, it is much harder to work with them in a logical way. Both of these aspects, however, fit with our hypothesis that the self-assembly that we have discovered is putting positively charged copper together with negatively charged sulfur-containing cystine.”

The research discovery was a team effort that included DeCoster and Louisiana Tech students at the bachelor, master and doctoral level. “The quality of my team in putting together a sustained effort to figure out what was needed to reproducibly carry out the new self-assembly methods and to simplify them really speaks well as to what can be accomplished at Louisiana Tech University,” DeCoster said. “Furthermore, the work is very multi-disciplinary, meaning that it required nanotechnology as well as biological and biochemical insights to make it all work, as well as some essential core instrumentation that we have at Louisiana Tech.”

DeCoster says the future of this research has some potentially high impacts. He and his team are speaking with colleagues and collaborators about how to test these new nanocomposites for applications in bioengineering and larger composites such as materials that would be large enough to be hand-held.

“Our recent publication of the work could generate some interest and new ideas,” said DeCoster. “We are working on new proposals to fund the research and to keep it moving forward. We are currently making these materials on an ‘as needed’ basis, knowing that they can be stored once generated, and if we discover new uses for the nanocomposites, then applications for the materials could lead to income generation through a start-up company that I have formed.”

Here’s a link to and a citation for the paper,

MediumGeneration of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium by Kinsey Cotton Kelly, Jessica R. Wasserman, Sneha Deodhar, Justin Huckaby, and Mark A. DeCoster. J. Vis. Exp. [Journal of Visual Experimentation; JoVE] (101), e52901, doi:10.3791/52901 (2015).

This paper/video is behind a paywall.