Applications In Nanobiotechnology Research Articles

Thermally induced Fe2O3 spikes decorated Ag/Fe2O3 nanocomposite fabrication for anti-bacterial and anti-cancer activities

In the context of anti-cellular catalytic permutations, the development of thermally-induced nanotechnology is of great importance. In this study, iron oxides (Fe2O3) decorated silver (Ag) core–shell nanocomposite was prepared using a green thermal decomposition process without using any additional chemicals. The nanocomposite was characterized for its composition, phase interactions, morphology, and stability using spectroscopic, thermogravimetric, and microscopic techniques. The resultant nanocomposite were also investigated against different types of bacteria and cancer cell lines. Both Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Klebsiella spp., E. coli, and Pseudomonas) growth was inhibited by the Ag/Fe2O3 nanocomposite. The highest 19 mm zone of inhibition (ZOI) was found for Staphylococcus aureus by the combined effect of Ag and Fe2O3. The antibiofilm efficacy of the prepared nanocomposites showed biofilm destruction of 82.56% Staphylococcus aureus and 51.06% Klebsiella spp. Furthermore, the nanocomposite resulted in 80–90% death of Hela and BHK-21 cells but displayed lower cell toxicity in the case of the Vero cell line. This pathway of nanocomposites preparation with particle surface engineering would open new doors in the fields of nanobiotechnology and nanobiomedical applications.

Phytofabrication, characterization, and evaluation of novel bioinspired selenium–iron (Se–Fe) nanocomposites using Allium sativum extract for bio-potential applications

Abstract Green nano-chemistry is an advanced research route covering eco-friendly fabrication approaches for synthesizing bimetallic nanocomposites (NCs) to enhance their therapeutic properties. The current study aims to phytofabrication, characterization, and bio-potential evaluation of novel selenium–iron (Se–Fe) NCs by utilizing garlic extract. The morphological and physicochemical features of Se–Fe NCs were evaluated by UV–visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray, Fourier transform infrared, X-ray diffraction, and Zeta potential analysis. The findings showed that garlic cloves extract was a promising capping and reducing agent for the formulation of the NC. To explore the antioxidant potential of a bioinspired Se–Fe NC, 2,2-diphenyl-1-picrylhydrazyl and reducing power assays were performed. Furthermore, antioxidant efficacy was confirmed through antimicrobial activities against clinical pathogens. Phytosynthesized Se–Fe NCs (25, 50, 75, and 100 ppm) showed a dose-dependent response. Higher concentrations of Se–Fe NCs impose a more potent antioxidant and antimicrobial potential. The astonishing findings suggest that phytochemicals in Allium sativum extract are useful reducing agents in the formulation of well-defined Se–Fe NCs, and such NCs could act as competitive inhibitors against pathogens. To the extent of our understanding, Se–Fe NC is the first time synthesized and demonstrates the distinctiveness of green chemistry and will give multifunctional applications in nano-biotechnology.

Programming assembly of biomimetic exosomes: An emerging theranostic nanomedicine platform.

Exosomes have emerged as a promising cell-free therapeutic approach. However, challenges in large-scale production, quality control, and heterogeneity must be overcome before they can be used clinically. Biomimetic exosomes containing key components of natural exosomes have been assembled through extrusion, artificial synthesis, and liposome fusion to address these limitations. These exosome-mimetics (EMs) possess similar morphology and function but provide higher yields, faster large-scale production, and similar size compared to conventional exosomes. This article provides an overview of the chemical and biological properties of various synthetic exosome systems, including nanovesicles (NVs), EMs, and hybrid exosomes. We highlight recent advances in the production and applications of nanobiotechnology and discuss the advantages, limitations, and potential clinical applications of programming assembly of exosome mimetics.

Degree-based topological indices of boron nanotubes

In the past two decades, boron nanotubes have received significant attention from researchers and scientists due to their wide-ranging applications in electronics, nanodevices, optical engineering, nanobiotechnology, and cosmetics. These nanotubular structures composed of boron present exceptional electrical and mechanical properties, making them highly potential nanomaterials. In this article, we study the molecular structure of significant classes of boron nanotubes, namely, trihexagonal boron nanotubes, triangular boron nanotubes, and boron-α nanotubes. Furthermore, we calculate various topological indices for these nanotubes, including the augmented Zagreb index, Sombor index, reduced Sombor index, sum-connectivity index, and arithmetic–geometric index. These indices hold substantial importance in assessing the physical, chemical, and biological characteristics of boron nanotubes.

Single-molecule analysis of osmolyte-mediated nanomechanical unfolding behavior of a protein domain

The small organic molecules, known as osmolytes being ubiquitously present in different cell types, affect protein folding, stability and aggregation. However, it is unknown how the osmolytes affect the nanomechanical unfolding behavior of protein domain. Here, we show the osmolyte-dependent mechanical unfolding properties of protein titin immunoglobulin-27 (I27) domain using an atomic force microscopy (AFM)-based single-molecule force spectroscopy. We found that amines and methylamines improved the mechanical stability of I27 domain, whereas polyols had no effect. Interestingly, glycine betaine (GB) or trimethylamine-N-oxide (TMAO) increased the average unfolding force of the protein domain. The kinetic parameters analyzed at single-molecule level reveal that stabilizing effect of osmolytes is due to a decrease in the unfolding rate constant of I27, which was confirmed by molecular dynamics simulations. Our study reveals different effects that diverse osmolytes have on the mechanical properties of the protein, and suggests the potential use of osmolytes in modulating the mechanical stability of proteins required for various nano-biotechnological applications.

QD-based fluorescent nanosensors: Production methods, optoelectronic properties, and recent food applications.

Food quality and safety are crucial public health concerns with global significance. In recent years, a series of fluorescence detection technologies have been widely used in the detection/monitoring of food quality and safety. Due to the advantages of wide detection range, high sensitivity, convenient and fast detection, and strong specificity, quantum dot (QD)-based fluorescent nanosensors have emerged as preferred candidates for food quality and safety analysis. In this comprehensive review, several common types of QD production methods are introduced, including colloidal synthesis, self-assembly, plasma synthesis, viral assembly, electrochemical assembly, and heavy-metal-free synthesis. The optoelectronic properties of QDs are described in detail at the electronic level, and the effect of food matrices on QDs was summarized. Recent advancements in the field of QD-based fluorescent nanosensors for trace level detection and monitoring of volatile components, heavy metal ions, food additives, pesticide residues, veterinary-drug residues, other chemical components, mycotoxins, foodborne pathogens, humidity, and temperature are also thoroughly summarized. Moreover, we discuss the limitations of the QD-based fluorescent nanosensors and present the challenges and future prospects for developing QD-based fluorescent nanosensors. As shown by numerous publications in the field, QD sensors have the advantages of strong anti-interference ability, convenient and quick operation, good linear response, and wide detection range. However, the reported assays are laboratory-focused and have not been industrialized and commercialized. Promising research needs to examine the potential applications of bionanotechnology in QD-based fluorescent nanosensors, and focus on the development of smart packaging films, labeled test strips, and portable kits-based sensors.

Synthetic α-Helical Nanopore Reactor for Chemical Sensing.

The use of nanopores for the single-molecule sensing of folded proteins and biomacromolecules has recently gained attention. Here, we introduce a simplified synthetic α-helical transmembrane pore, pPorA, as a nanoreactor and sensor that exhibits functional versatility comparable to that of engineered protein and DNA nanopores. The pore, built from the assembly of synthetic 40-amino-acid-long peptides, is designed to contain cysteine residues within the lumen and at the pore terminus for site-specific chemical modification probed using single-channel electrical recordings. The reaction of the pore with differently charged activated thiol reagents was studied, wherein positively charged reagents electrophoretically driven into the pore resulted in pore blocking in discrete steps upon covalent bond formation. The asymmetric blockage patterns resulting from cis and trans-side addition of reagents reveal the pore orientation in the lipid membrane. Furthermore, activated PEG thiols covalently blocked the pores over a longer duration in a charge-independent manner, establishing the large diameter and orientation of the formed pores. While the covalent binding of thiol reagents caused a drop in the pore conductance, cationic cyclic octasaccharides produced time-resolved translocation events, confirming the structural flexibility and tunability of the pores. The ability of the pore to accommodate large analytes and the considerable current amplitude variation following bond formation events are promising for developing platforms to resolve multistep chemical reactions at the single-molecule level for applications in synthetic nanobiotechnology.

Silver and gold nanoparticles: Eco-friendly synthesis, antibiofilm, antiviral, and anticancer bioactivities

For the first time in this study, silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were green synthesized by the cost-effective and eco-friendly procedure using Cotton seed meal and Fodder yeast extracts. The biosynthesized NPs were characterized by UV–Vis spectroscopy, dynamic light scattering analysis (DLS), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and fourier-transform infrared (FTIR) spectroscopy. Furthermore, the biosynthesized NPs were tested in vitro against biofilm formation by some pathogenic negative bacteria (Escherichia coli, Proteus mirabilis, Klebsiella sp., Salmonella sp., and Pseudomonas aeruginosa) and negative bacteria (staphylococcus aureus) as well as against human denovirus serotype 5 (HAdV-5) and anticancer activity using HepG2 hepatocarcinoma cells. UV–Vis absorption spectra of reaction mixture of AgNPs and AuNPs exhibited maximum absorbance at 440 nm and 540 nm, respectively. This finding was confirmed by DLS measurements that the highest intensity of the AgNPs and AuNPs were 84 nm and 73.9 nm, respectively. FTIR measurements identified some functional groups detected in Cotton seed meal and Fodder yeast extracts that could be responsible for reduction of silver and gold ions to metallic silver and gold. The morphologies and particle size of AgNPs and AuNPs were confirmed by the TEM and SAED pattern analysis. Biosynthesized AgNPs and AuNPs showed good inhibitory effects against biofilms produced by Escherichia coli, Proteus mirabilis, Klebsiella sp., Salmonella sp., Pseudomonas aeruginosa, and Staphylococcus aureus. In addition, they showed anticancer activities against hepatocellular carcinoma (HepG-2) and antiviral activity against human adenovirus serotype 5 infection in vitro. Finally, the results of this study is expected to be extremely helpful to nano-biotechnology, pharmaceutical, and food packing applications through developing antimicrobial and/or an anticancer drugs from ecofriendly and inexpensive nanoparticles with multi-potentiality.

Light-harvesting proteins intermolecular order in the Langmuir-Blodgett (LB) nanofilms – methods and applications.

Light-harvesting proteins can be used as versatile building blocks for the realization of functional biomaterials. A pathway to the hierarchical arrangement of protein molecules into functional biomaterials is provided by mesoscale (>50 nm) self-assembly. This nanotechnological approach opens new avenue in applications of light-harvesting proteins in materials science and bioelectronics (e.g., biosensors, energy-conversion devices).Phycocyanin (PC), a phycobiliprotein found in the majority of cyanobacteria and red algae’s photosynthetic light-harvesting phycobilisome complex, has the potential to be used in a wide range of nanobiotechnological applications, such as biological photovoltaic devices and as a natural photosensitizer for dye-sensitized solar cells. However, such applications frequently need for certain operating conditions, with thermal stability as one of the most crucial. Here we compare three advanced methods: Cryo-EM, X-ray nanodifraction and XFEL, previously used for probing local temperature-induced self-assembly in thermally annealed PC LB multilayered nanofilms.

Structural and optical properties of C70 fullerenes in aqueous solution

The simple method of preparation of highly stable and purified C70 fullerene aqueous solution (C70FAS) is proposed. The features of structural stabilization of C70 fullerenes in an aqueous solution by studying their structural and optical properties using Raman, photoluminescence, infrared reflection-absorption, UV–VIS absorption, and dynamic light scattering spectroscopy methods were analyzed. The experimental results showed that the most likely mechanism for C70 fullerenes stabilization in water is surface hydroxylation with covalent attachment of water hydroxyls to C70 fullerene carbons. Raman and infrared absorption spectra of C70FAS showed characteristic vibrational bands of C70 fullerenes with a slight broadening and low-frequency shift of ∼1 cm−1, indicating the attachment of water hydroxyls to the C70 fullerene carbons. The photoluminescence spectra showed excitonic emission bands of C70 molecules with intensity depending on their content. UV–VIS absorption spectra demonstrate the absorption bands typical for monomeric C70 fullerene. Finally, the dynamic light scattering data confirmed that C70FAS is a typical colloidal fluid containing both individual C70 molecules and their nano aggregates up to 100 nm. These findings provide insights into the stabilization mechanism of C70 fullerenes in water and may have implications for their potential application in nanobiotechnology.

Self-accelerated DNA walker mediated electrochemical biosensor for rapid and ultrasensitive detection of microRNA

Herein, we developed a novel three-dimensional (3D) self-accelerated DNA walker (SADW) which progressively expedite walking rate by unlocking the more walking arm continuously in walker process to construct electrochemical biosensor for ultrasensitive detection of microRNA. Particularly, we skillfully introduced a target analogue sequence in the double-loop hairpin, which could be released in the walking process of SADW, then rapidly activating more silenced walking strands to achieve the continuous self-acceleration, resulting in the expedited reaction rate. Surprisingly, the average reaction rate of SADW was quite higher than that of traditional 3D self-circulating DNA walkers (DW) under pretty low target miRNA concentration, which is ascribed to the outstanding acceleration process of the SADW, readily conquering the major predicaments of DW in detecting target with traces concentration: slow reaction rate and low sensitivity. This way, the elaborated SADW is favorably applied in the ultrasensitive and rapid detection of miRNA-21 in tumor cancer cell lysates with a detection limit down to 5.81 aM which was far from lower than the detection limit of DW. This approach develops the novel generation of widespread strategy for the applications in clinic diagnose, biosensing assay, and DNA nanobiotechnology.

Application of Nanobiotechnology in Enabling Plants to Overcome Water-logging Stress: A Review

Abiotic stresses adversely affect plant growth and ultimately crop productivity. Of these, water-logging is the most widespread and most commonly experienced stress factor. While water is essential for all plant growth and development processes, waterlogging is an obstacle to sustainable agriculture. Recent FAO reports indicate that universal crop production must be enhanced by 70% by 2050 in order to meet the growing demand for food by an estimated 2.3 billion people. As demand for food increases, there is an urgent need to identify environment-friendly strategies capable of being accepted and adopted widely to enhance crop yields and mitigate the effects of climate change. Nanotechnology as a science of manipulating materials at the nano-scale has significant potential to enhance agricultural productivity by nonconventional means. This technology has been gaining momentum lately as a possible solution to reduce the adverse effects associated with various stresses, particularly with waterlogging, to enhance future food security. This paper discusses the potential applications of nanoparticles to achieve sustainable crop productivity, together with their impact on the mechanism of tolerance to waterlogging stress.

The UNANO consortium aims at uniting bionanotechnology research in Europe

The UNANO consortium consists of laboratories from eight European research universities that explore biomolecules as building blocks for the assembly of nanostructures and nanomachines. UNANO aims at uniting bionanotechnology researchers across Europe and transcending disciplinary boundaries to synergize research impact and explore applications of bionanotechnology.

Improvement of Cellulomonas fimi endoglucanase CenA by multienzymatic display on a decameric structural scaffold.

The development of multifunctional particles using polymeric scaffolds is an emerging technology for many nanobiotechnological applications. Here we present a system for the production of multifunctional complexes, based on the high affinity non-covalent interaction of cohesin and dockerin modules complementary fused to decameric Brucella abortus lumazine synthase (BLS) subunits, and selected target proteins, respectively. The cohesin-BLS scaffold was solubly expressed in high yield in Escherichia coli, and revealed a high thermostability. The production of multienzymatic particles using this system was evaluated using the catalytic domain of Cellulomonas fimi endoglucanase CenA recombinantly fused to a dockerin module. Coupling of the enzyme to the scaffold was highly efficient and occurred with the expected stoichiometry. The decavalent enzymatic complexes obtained showed higher cellulolytic activity and association to the substrate compared to equivalent amounts of the free enzyme. This phenomenon was dependent on the multiplicity and proximity of the enzymes coupled to the scaffold, and was attributed to an avidity effect in the polyvalent enzyme interaction with the substrate. Our results highlight the usefulness of the scaffold presented in this work for the development of multifunctional particles, and the improvement of lignocellulose degradation among other applications. KEY POINTS: • New system for multifunctional particle production using the BLS scaffold • Higher cellulolytic activity of polyvalent endoglucanase compared to the free enzyme • Amount of enzyme associated to cellulose is higher for the polyvalent endoglucanase.

Photoactivated Artificial Molecular Motors.

Accurate control of long-range motion at the molecular scale holds great potential for the development of ground-breaking applications in energy storage and bionanotechnology. The past decade has seen tremendous development in this area, with a focus on the directional operation away from thermal equilibrium, giving rise to tailored man-made molecular motors. As light is a highly tunable, controllable, clean, and renewable source of energy, photochemical processes are appealing to activate molecular motors. Nonetheless, the successful operation of molecular motors fueled by light is a highly challenging task, which requires a judicious coupling of thermal and photoinduced reactions. In this paper, we focus on the key aspects of light-driven artificial molecular motors with the aid of recent examples. A critical assessment of the criteria for the design, operation, and technological potential of such systems is provided, along with a perspective view on future advances in this exciting research area.

COMPLEX-FORMING PROPERTIES OF SYNTHETIC PYRIMIDINONE NUCLEOSIDES WITH Ag(I) IONS IN AN AQUEOUS SOLUTION

The present work describes the complexation properties of two synthetic nucleosides (used as ligands), i.e. β-D-ribofuranoside-4-pyrimidinone (ribo) and β-D-deoxyribofuranoside-4-pyrimidinone (deoxy) with Ag(I) ions in aqueous solution. The stability constants of the studied coordination entities were calculated potentiometrically. The logarithm values of the overall stability constants of the coordination entities were found to be [Ag-deoxy]+ = 3.07, [Ag-(deoxy)2]+ = 6.90, [Ag-ribo]+ = 3.00 and [Ag-(ribo)2]+ = 6.63. Based on the species distribution curves as a function of CL/CM, the percentage of each coordination entity formed in aqueous solution was estimated (12 % [Ag-deoxy]+; 36 % [Ag-(deoxy)2]+; 16 % [Ag-ribo]+; 26 % [Ag-(ribo)2]+). It was found that the ligands form coordination entities with Ag(I) ions with stoichiometric ratios M : L = 1 : 1 and 1 : 2. Such coordination entities may show potential antiviral, antibacterial, and antitumor properties, which warrants further in vitro and in vivo studies. They may also be of great interest for their application in nanobiotechnology.

Enzymatic oxidation of tyrosine enantiomers into biomimetic pigments with enhanced performance for hair dyeing

Most natural biomolecules have two enantiomeric forms and can exist in either of them. Despite the L-type homochirality of natural biopolymers composed of amino acids, a great deal of effort has been devoted to the systems in which chirality dictates molecular self-assembly and corresponding properties. Previously, we demonstrated that chemical pre-modification of tyrosine (L-Tyr) inspired by natural eumelanin can obtain colorful pigments and surface coatings, but their characteristics like stability still have development space. Here, the racemic reaction systems of tyrosine derivatives (L/D-Tyr, Boc-L/D-Tyr and Cbz-L/D-Tyr) were designed, and we proved that substrate molecular chirality can affect the reaction rate of the oxidation process, change the intermolecular force and arrangement during assembly, thus influencing the morphology, structures, and properties of the biomimetic pigment materials. At the same time, we found that L + D-tyrosine derivatives can be oxidized and deposited on hair surfaces to obtain the color effect of black and red-brown series, and achieve green-safe biological hair dyeing. Compared with previous studies, it has faster coloring speed, higher color saturation, stronger color fixation stability, good mechanical strength and biocompatibility, providing a new idea for the manufacture of chiral-inspired advanced materials with bio-nanotechnology applications.

The potential of myosin and actin in nanobiotechnology.

Since the late 1990s, efforts have been made to utilize cytoskeletal filaments, propelled by molecular motors, for nanobiotechnological applications, for example, in biosensing and parallel computation. This work has led to in-depth insights into the advantages and challenges of such motor-based systems, and has yielded small-scale, proof-of-principle applications but, to date, no commercially viable devices. Additionally, these studies have also elucidated fundamental motor and filament properties, as well as providing other insights obtained from biophysical assays in which molecular motors and other proteins are immobilized on artificial surfaces. In this Perspective, I discuss the progress towards practically viable applications achieved so far using the myosin II-actin motor-filament system. I also highlight several fundamental pieces of insights derived from the studies. Finally, I consider what may be required to achieve real devices in the future or at least to allow future studies with a satisfactory cost-benefit ratio.

Single-Molecule Sizing through Nanocavity Confinement.

An approach relying on nanocavity confinement is developed in this paper for the sizing of nanoscale particles and single biomolecules in solution. The approach, termed nanocavity diffusional sizing (NDS), measures particle residence times within nanofluidic cavities to determine their hydrodynamic radii. Using theoretical modeling and simulations, we show that the residence time of particles within nanocavities above a critical time scale depends on the diffusion coefficient of the particle, which allows the estimation of the particle's size. We demonstrate this approach experimentally through the measurement of particle residence times within nanofluidic cavities using single-molecule confocal microscopy. Our data show that the residence times scale linearly with the sizes of nanoscale colloids, protein aggregates, and single DNA oligonucleotides. NDS thus constitutes a new single molecule optofluidic approach that allows rapid and quantitative sizing of nanoscale particles for potential applications in nanobiotechnology, biophysics, and clinical diagnostics.

Textile Functionalization by Porous Protein Crystal Conjugation and Guest Molecule Loading

Protein crystals are versatile nanostructured materials that can be readily engineered for applications in nanomedicine and nanobiotechnology. Despite their versatility, the small size of typical individual protein crystals (less than one cubic mm) presents challenges for macroscale applications. One way to overcome this limitation is by immobilizing protein crystals onto larger substrates. Cotton is composed primarily of cellulose, the most common natural fiber in the world, and is routinely used in numerous material applications including textiles, explosives, paper, and bookbinding. Here, two types of protein crystals were conjugated to the cellulosic substrate of cotton fabric using a 1,1′-carbonyldiimidazole/aldehyde mediated coupling protocol. The efficacy of this attachment was assessed via accelerated laundering and quantified by fluorescence imaging. The ability to load guest molecules of varying sizes into the scaffold structure of the conjugated protein crystals was also assessed. This work demonstrates the potential to create multifunctional textiles by incorporating diverse protein crystal scaffolds that can be infused with a multiplicity of useful guest molecules. Cargo molecule loading and release kinetics will depend on the size of the guest molecules as well as the protein crystal solvent channel geometry. Here, we demonstrate the loading of a small molecule dye into the small pores of hen egg white lysozyme crystals and a model enzyme into the 13-nm pores delimited by “CJ” crystals composed of an isoprenoid-binding protein from Campylerbacter jejuni.