Knowledge-sourcing strategies for cross-disciplinarity in bionanotechnology

interdisciplinarity, collaboration, bionanotechnology, research, knowledge-sourcing, molecular motors

Bionanotechnology

Bionanotechnology is a subset of nanotechnology: atom-level engineering and manufacturing using biological precedents for guidance. It is also closely married to biotechnology, but adds the ability to design and modify the atomic-level details of the objects created

Polyelectrolyte-modified cowpea mosaic virus for the synthesis of gold nanoparticles

Polyelectrolyte surface-modified cowpea mosaic virus (CPMV) can be used for the templated synthesis of narrowly dispersed gold nanoparticles. Cationic polyelectrolyte, poly(allylamine) hydrochloride, is electrostatically bound to the external surface of the virus capsid. The polyelectrolyte-coated CPMV promotes adsorption of aqueous gold hydroxide anionic species, prepared from gold(III) chloride and potassium carbonate, that are easily reduced to form CPMV-templated gold nanoparticles. The process is simple and environmentally benign using only water as solvent at ambient temperature

Templated mineralization by charge-modified cowpea mosaic virus

Templated mineralization of virus particles provides routes to narrowly dispersed nanoparticles that are not readily prepared by other means. The templated mineralization of metal or metal oxide on the external surface of wild-type cowpea mosaic virus (CPMV), a plant virus, is facilitated by increasing the external surface negative charge. This is achieved by the chemical modification of surface lysine groups by succinic anhydride. Hence, for example, treatment of charge-modified CPMV succinamate with a 1:2 mixture of iron(II) and iron(III) salts, followed by raising the pH to 10.2, led to the formation of narrowly dispersed, CPMV-templated, magnetite (Fe3O4) nanoparticles

Chitin and lignin. Natural ingredients from waste materials to make innovative and healthy products for humans and plant

In a globalized world, plants are continually cut to obtain free land for intensive farming without remembering their important function in the planet ecosystem. They produce oxygen eliminating the carbon dioxide excess, contributing to reduce the pollution thus giving a great support to our health. According to the World Health Organization (WHO), air pollution -both outdoor and indoor- is nowadays "the biggest environmental risk to health carrying responsibility for about one in every nine deaths" (WHO, 2016). Outdoor pollution alone, in fact, kills around 3 million people each year. At this purpose however, it is necessary to remember that indoor emission of nanoparticles (NP) represent 50-80% of human exposure, calculated from 10.000 to 249.000 NP/mL air-while in polluted air NP are from ~10.000 to 50.000 NP/mL (Nohynek, 2011). Thus, there is a strict necessity "to consider air pollution as a global health priority in the sustainable development agenda" (WHO, 2016). Moreover, plants, multicellular organisms, as well as humans have evolved several mechanisms of defense and sensor systems to detect danger and prevent entry of most foreign material (Janeway et al, 2001). The sensors can direct and assist the host defenses by the use of specialized cells that ingest and digest foreign material. This protective non-specific method is called innate immune system, also connected with certain specific molecular patterns recognition associated with invading microbes or tissue damage (Nurnberger et al., 2004). In addition to innate immunity, vertebrates have evolved an adaptive immune system that relies on many antigen receptors, expressed by specialized immune cells. Unlike vertebrates, plants lack mobile defender cells and respond to infection by a two-branched immune system (Jones et al., 2006). The first branch recognizes and responds to all the common microbial molecules, while the second responds to pathogen virulence factors only. However, both plants and mammals have as first-line defense a barrier that, separating and shielding the interior of the body from the surrounding environment, represents the initial obstacle to be overcame from any pathogenic microorganisms. This barrier not only provides a physical separation, but releases also substances with antimicrobial properties. Moreover, when the first-line barrier has been breached, sensor systems are activated to give information to other components of the host defenses. Thus, while mammals activate, for example, the toll-like receptors capable to recognize families of compounds unique to microbes, plants release specialized compounds known as elicitors, signaling molecules able to induce their defense systems (Trouvelot et al., 2014). Examples of common ingredients, used from both plant and mammal as elicitors and defense-related compounds, are chitin and lignin. In this work, these materials will be briefly reviewed and results of chitin nanofibrils production and usage is reported. Finally, possible usage of combined chitin-lignin nanofibrils in commercial products will be pointed out

Protein Enrichment Of Pycnoporus Sanguineus For Silver Nanoparticles Synthesis

Controlling sizes of nanomaterials are attracting a great deal of attention because of their unit properties for achieving specific processes especially in biological and medical applications. In this context, Ag which possesses good antimicrobial effects is of interest. A simple and effective approach for the synthesis of Ag nanoparticles by reduction mechanism of proteins synthesized by several species of white rot fungi was studied. Pycnoporus sanguineus was found to produce smallest Ag nanoparticles with degree of monodispersity. A Box-Behnken design was employed to optimize a fermentation medium for the production of protein by the selected fungi. The four variables involved in the study were glucose, malt extract, yeast extract and pH. The optimized medium contained 8.39 gL-1, 18.34 gL-1, 14.71 gL-1 of yeast extract, glucose and malt extract respectively with initial pH 6.66; and produced the maximum protein at 0.858 gL-1. Kinetic growth of the fungi, glucose consumption and product formation of the tested fungus were also reported. It is showed that at initial glucose concentration of 20gL-1, Richard-modified logistic model (R2 =0.9839) for microbial growth, modified Gompertz model (R2 =0.9610) for product formation and first order non-growth associate (R2 =0.9736) for glucose consumption were fittd well with the experimental data. Sequential optimization strategy based on one-factor-at-a-time (OFAT) method and statistical experimental design were employed to optimize the process parameters for the enhancement of Ag nanoparticles synthesis. Based on the OFAT method, three significant factors influencing the size of Ag nanoparticles such as AgNO3 concentration, incubation temperature and agitation spee

Lipid-modulated assembly of magnetized iron-filled carbon nanotubes in millimeter-scale structures

Biomolecule-functionalized carbon nanotubes (CNTs) combine the molecular recognition properties of biomaterials with the electrical properties of nanoscale solid state transducers. Application of this hybrid material in bioelectronic devices requires the development of methods for the reproducible self-assembly of CNTs into higher-order structures in an aqueous environment. To this end, we have studied pattern formation of lipid-coated Fe-filled CNTs, with lengths in the 1–5 µm range, by controlled evaporation of aqueous CNT-lipid suspensions. Novel diffusion limited aggregation structures composed of end-to-end oriented nanotubes were observed by optical and atomic force microscopy. Significantly, the lateral dimension of assemblies of magnetized Fe-filled CNTs was in the millimeter range. Control experiments in the absence of lipids and without magnetization indicated that the formation of these long linear nanotube patterns is driven by a subtle interplay between radial flow forces in the evaporating droplet, lipid-modulated van der Waals forces, and magnetic dipole–dipole interactions. Keywords

Accurate DOSY measure of out-of-equilibrium systems by permutated DOSY (p-DOSY)

NMR spectroscopy is an excellent tool for monitoring in-situ chemical reactions. In particular, DOSY measurement is well suited to characterize transient species by the determination of their sizes. However, here we bring to light a difficulty in the DOSY experiments performed in out-of-equilibrium systems. On such a system, the evolution of the concentration of species interferes with the measurement process, and creates a bias on the diffusion coefficient determination that may lead to erroneous interpretations. We show that a random permutation of the series of gradient strengths used during the DOSY experiment allows to average out this bias. This approach, that we name p-DOSY does not require changes in the the pulse sequences nor in the processing software, and restores completely the full accuracy of the measure. This technique is demonstrated on the monitoring of the anomerization reaction of \alpha- to \beta-glucose.Comment: Revised version - 15 pages, 8 figures program archived at 10.5281/zenodo.1926