Various Applications Of Nanotechnology Research Articles

Expression of Rhizobium tropici phytochelatin synthase in Escherichia coli resulted in increased bacterial selenium nanoparticle synthesis

Phytochelatins are the main heavy metal detoxifying peptides found in plants. In the present study, Escherichia coli DH5α cells were transformed with the phytochelatin synthase gene from Rhizobium tropici. The tolerance of these recombinant bacterial cells to heavy metals as well as their capacity to synthesize selenium nanoparticles were explored. The functional studies showed the recombinant E. coli grew faster and achieved a higher cell density after overnight cultivation in comparison with the control cells. In addition, the recombinant E. coli had a higher tolerance to copper, nickel, zinc, and cadmium ions. Importantly, the cells had increased capacity to synthesize selenium nanoparticles. Our results suggested that the phytochelatin synthase gene transformed E. coli DH5α cells can be used to produce selenium nanoparticles in large scale for various applications in nanotechnology and biomedicine.

A theoretical study of 4-Mercaptobenzoic acid assembled on Ag for surface-enhanced raman scattering applications

Thiols are widely used in the preparation of self-assembled monolayers (SAMs) on metallic surfaces such as Ag, Cu and Au because of their strong affinity for such surfaces. These SAMs have various applications in nanotechnology and supramolecular chemistry. However, the chemistry of the metal surface and the thiol end is still vaguely understood, yet it fundamentally governs the properties of the SAMs. This paper reports density functional theory (DFT) and corroborating experimental findings focusing on vibrational Raman spectroscopy of Ag-Mercaptobenzoic acid (AgMBA) SAMs. The 4-MBA thiol was self-assembled onto Ag (111) and (100) fcc surfaces via both the COO- and S- ends. The experimental AgMBA vibrational frequencies showed the interaction of the 4-MBA with the Ag surface from both the S- and COO- atoms and the observation was supported by the our own n-layered integrated molecular orbital and molecular mechanics (ONIOM) calculated surface-enhanced Raman spectroscopy spectra and DFT thermodynamic calculations. The Ag(100)MBA self-assembled via the COO- end had the highest enthalpy of adsorption of -310.34 kJ/mol and it was the most stable plane contradicting the sulphur end consensus on previous papers. The adsorption of the 4-MBA moiety on the Ag surface was interplayed by the corrugation potential of the exposed surface and the thiol’s aromatic nature which resulted in the adsorption of 4-MBA predominately via the carbonyl end at slightly acidic pH conditions and a deprotonated thiol end.

Binding Affinity and Conformational Preferences Influence Kinetic Stability of Short Oligonucleotides on Carbon Nanotubes

AbstractDNA polymer‐wrapped single‐walled carbon nanotubes (SWNTs) finds a widespread use in a variety of nanotechnology applications. Molecular dynamics (MD) simulations and experiments are used to explore the relationship between structural conformation, binding affinity, and kinetic stability for short single‐stranded oligonucleotides adsorbed on SWNTs. The conformation of 36 oligonucleotide sequences on (9,4) SWNT is computationally screened, where the polymer lengths are selected so the polymers can, to a first approximation, wrap once around the SWNT circumference. The identified conformations can be broadly classified into “rings” and “non‐rings.” Then, 2D conformational free energy landscapes for selected sequences are obtained by temperature replica exchange calculations. Propensity for “ring” conformations are driven primarily by sequence chemistry and the ability of the polymer to form compact structures. However, ring‐formation probability is found to be uncorrelated with free energy of oligonucleotide binding to SWNTs (∆Gbind). Conformational analyses of oligonucleotides, computed free energy of binding of oligonucleotides to SWNTs, and experimentally determined kinetic stability measurements show that ∆Gbind is the primary correlate for kinetic stability. The probability of the sequence to adopt a compact, ring‐like conformation is shown to play a secondary role that still contributes measurably and positively to kinetic stability.

Study of Nanotechnology and Its Application

Nanotechnology is new frontiers of this century. The world is facing great challenges in meeting rising demands for basic commodities(e.g., food, water and energy), finished goods (e.g., cellphones, cars and airplanes) and services (e.g., shelter, healthcare and employment) while reducing and minimizing the impact of human activities on Earth’s global environment and climate. Nanotechnology has emerged as a versatile platform that could provide efficient, cost-effective and environmentally acceptable solutions to the global sustainability challenges facing society. In recent years there has been a rapid increase in nanotechnology in the fields of medicine and more specifically in targeted drug delivery. Opportunities of utilizing nanotechnology to address global challenges in (1) water purification, (2) clean energy technologies, (3) greenhouse gases management, (4) materials supply and utilization, and (5) green manufacturing and hemistry. Smart delivery of nutrients, bio-separation of proteins, rapid sampling of biological and chemical contaminants, and nano encapsulation of nutraceuticals are some of the emerging topics of nanotechnology for food and agriculture. Nanotechnology is helping to considerably improve, even revolutionize, many technology and Industry sectors: information technology, energy, environmental science, medicine, homeland security, food safety, and transportation, among many others. Today’s nanotechnology harnesses current progress in chemistry, physics, materials science, and biotechnology to create novel materials that have unique properties because their structures are determined on the nanometer scale. This paper summarizes the various applications of nanotechnology in recent decades Nanotechnology is one of the leading scientific fields today since it combines knowledge from the fields of Physics, Chemistry, Biology, Medicine, Informatics, and Engineering. It is an emerging technological field with great potential to lead in great breakthroughs that can be applied in real life. Novel Nano and biomaterials, and Nano devices are fabricated and controlled by nanotechnology tools and techniques, which investigate and tune the properties, responses, and functions of living and non-living matter, at sizes below100 nm. The application and use of Nano materials in electronic and mechanical devices, in optical and magnetic components, quantum computing, tissue engineering, and other biotechnologies, with smallest features, widths well below 100 nm, are the economically most important parts of the nanotechnology nowadays and presumably in the near future. The number of Nano products is rapidly growing since more and more Nano engineered materials are reaching the global market the continuous revolution in nanotechnology will result in the fabrication of nanomaterial with properties and functionalities which are going to have positive changes in the lives of our citizens, be it in health, environment, electronics or any other field. In the energy generation challenge where the conventional fuel resources cannot remain the dominant energy source, taking into account the increasing consumption demand and the CO2 .Emissions alternative renewable energy sources based on new technologies have to be promoted. Innovative solar cell technologies that utilize nanostructured materials and composite systems such as organic photovoltaic offer great technological potential due to their attractive properties such as the potential of large-scale and low-cost roll-to-roll manufacturing processes

A Review on Biological Building Blocks and its Applications in Nanotechnology

Biological building blocks are the basis of living organisms and its potentials are gaining more attention over a wide range of applications. major biological building blocks that exist in the universe have been taken into consideration in this paper, which are proteins, lipids, carbohydrates and nucleic acids. Due to their small size, they are such molecules which can be considered by the Nano level structures therefore have been incorporated in various applications of nanotechnology and microbiology. Taking into consideration the structural and chemical properties of these biological building blocks, further application on each individual biological building block has been covered in multiple fields, but mainly in the medical and pharmaceutical industry. The applications also concern optical imaging, precision measurement of biomolecules, Nano biomaterial synthesis and biosensors. Despite the various advantages of these applications like improved efficiency of various processes, the shared limitations of these applications stand to be difficult technique for synthesis and development due to Nano size dimension consideration. Thus, the future scope of use of biological building blocks in nanotechnology is very ambitious and promising.

Implementation of nanotechnology in fuel cells

In this paper deals with the various applications of nanotechnology in fuel cells. One of the major problems in today’s world is power crisis. This problem can be over come by using fuel cells. This fuel cells has another advantage that they are zero-emissive in nature, comparing to fossil fuels. Because they use hydrogen and oxygen as fuels, and the combustion product is also just water, which never causes pollution to the environment. Thus, the pollution can be controlled and indirectly preventing global warming, which is also one of the gigantic problem, now a days. But, any how, the fuel cells also pollute the environment indirectly, during the process of production of hydrogen required as fuel. The implementation of nanotechnology in this method practically makes fuel cells, non-polluting. Here comes another problem of storing hydrogen as required by the fuel cells. This problem can also be over come by implementing nanotechnology. The carbon-nanotubes can be used in storing hydrogen efficiently, as per the requirements.

The effects of osmolytes on in vitro kinesin-microtubule motility assays.

The gliding motility of microtubule filaments has been used to study the biophysical properties of kinesin motors, as well as being used in a variety of nanotechnological applications. While microtubules are generally stabilized in vitro with paclitaxel (Taxol®), osmolytes such as polyethylene glycol (PEG) and trimethylamine N-oxide (TMAO) are also able to inhibit depolymerization over extended periods of time. High concentrations of TMAO have also been reported to reversibly inhibit kinesin motility of paclitaxel-stabilized microtubules. Here, we examined the effects of the osmolytes PEG, TMAO, and glycerol on stabilizing microtubules during gliding motility on kinesin-coated substrates. As previously observed, microtubule depolymerization was inhibited in a concentration dependent manner by the addition of the different osmolytes. Kinesin-driven motility also exhibited concentration dependent effects with the addition of the osmolytes, specifically reducing the velocity, increasing rates of pinning, and altering trajectories of the microtubules. These data suggest that there is a delicate balance between the ability of osmolytes to stabilize microtubules without inhibiting motility. Overall, these findings provide a more comprehensive understanding of how osmolytes affect the dynamics of microtubules and kinesin motors, and their interactions in crowded environments.

Enhanced Silver Nanoparticle Synthesis by Escherichia Coli Transformed with Candida Albicans Metallothionein Gene.

In this study, the metallothionein gene of Candida albicans (C. albicans) was assembled by polymerase chain reaction (PCR), inserted into pUC19 vector, and further transformed into Escherichia coli (E. coli) DH5α cells. The capacity of these recombinant E. coli DH5α cells to synthesize silver nanoparticles was examined. Our results demonstrated that the expression of C. albicans metallothionein in E. coli promoted the bacterial tolerance to metal ions and increased yield of silver nanoparticle synthesis. The compositional and morphological analysis of the silver nanoparticles revealed that silver nanoparticles synthesized by the engineered E. coli cells are around 20 nm in size, and spherical in shape. Importantly, the silver nanoparticles produced by the engineered cells were more homogeneous in shape and size than those produced by bacteria lack of the C. albicans metallothionein. Our study provided preliminary information for further development of the engineered E. coli as a platform for large-scale production of uniform nanoparticles for various applications in nanotechnology.

Advances in nanomedical applications: diagnostic, therapeutic, immunization, and vaccine production.

In the last decades, nanotechnology-based tools started to draw the attention of research worldwide. They offer economic, rapid, effective, and highly specific solutions for most medical issues. As a result, the international demand of nanomaterials is expanding very rapidly. It was estimated that the market of nanomaterials was about $2.6 trillion in 2015. In medicine, various applications of nanotechnology proved their potential to revolutionize medical diagnosis, immunization, treatment, and even health care products. The loading substances can be coupled with a large set of nanoparticles (NPs) by many means: chemically (conjugation), physically (encapsulation), or via adsorption. The use of the suitable loading nanosubstance depends on the application purpose. They can be used to deliver various chemicals (drugs, chemotherapeutic agents, or imaging substances), or biological substances (antigens, antibodies, RNA, or DNA) through endocytosis. They can even be used to deliver light and heat to their target cells when needed. The present review provides a brief overview about the structure and shape of available NPs and discusses their applications in the medical sciences.

Preparation of Carbon Nanomembranes without Chemically Active Groups.

The electron-irradiation-induced synthesis of carbon nanomembranes (CNMs) from aromatic thiol-based self-assembled monolayers (SAMs) on gold substrate is a well-established method to form molecular thin nanosheets. These molecular two-dimensional materials can be prepared with tunable properties; therefore, they find a variety of applications in nanotechnology ranging from ultrafiltration to nanobiosensors. However, no chemically inert CNM was fabricated up to now, as the reactive thiol group is present on the membrane surface even after transferring it to other substrates. Here, we study the electron irradiation of carboxylic acid-based SAMs on a silver substrate as an alternative route for CNM formation. Our analysis, based on a combination of X-ray photoelectron spectroscopy and scanning electron microscopy demonstrates that for this type of SAMs, purely carbonaceous CNMs with tunable porosity can be obtained.

Properties of Zinc Ferrite Nanoparticles Due to PVP Mediation and Annealing at 500°C

In contributing to the improvement of Ferrite Magnetic nanoparticles, the effects of Poly (Vinyl Pyrrolidone) (PVP) and annealing on the structural and magnetic properties of Zinc ferrite nanoparticles (ZFNPs) synthesis were investigated in this work. The effects were evaluated using the X-ray diffraction (XRD) spectroscopy, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Vi-brating sample magnetometer (VSM). The XRD analysis confirms a good formation of the inverse spinel crystal structure with an average particle size of 1.3 nm to 15.2 nm and from 1.6 nm to 21.1 nm for the ZFNPs as-prepared and PVP mediated ZFNPs for the un-annealed and annealed samples, respectively. The SEM image reveals an increase in the particle size for both the as-prepared and PVP mediated samples after annealing at 500°C. The FTIR also reveals the inverse spinel structure for the as-prepared and annealed samples, which witnesses a vibrational red shift towards a higher wave number for the annealed samples. The VSM analysis indicates the superparamagnetic behavior of PVP mediated and annealed sample with zero remanence magnetization (Mr) and Coercivity (Hc). The saturation magnetization (Ms) increases from 1.31 emu/g, for the as-prepared samples, to 4.31 emu/g after the annealing and from 1.18 emu/g, for the PVP mediated, to 6.38 emu/g after annealing. These effects have been attributed to the cationic re-arrangement on the lattice site after the annealing. This presents a superior material for various applications in nanotechnology.

Advanced applications of nanotechnology in veterinary medicine.

The invention of new techniques to manipulate materials at their nanoscale had an evolutionary effect on various medical sciences. At the time, there are thousands of nanomaterials which can be divided according to their shape, origin, or their application. The nanotechnology provided new solutions for old problems. In medical sciences, they are used for diagnostic or therapeutic purposes. They can also be applied in the preparation of nanovaccines and nanoadjuvants. Their use in the treatment of cancer and in gene therapy opened the door for a new era in medicine. Recently, various applications of nanotechnology started to find their way in the veterinary sector. They increasingly invade animal therapeutics, diagnostics, production of veterinary vaccines, farm disinfectants, for animal breeding and reproduction, and even the field of animal nutrition. Their replacement of commonly used antibiotics directly reflects on the public health. By so doing, they minimize the problem of drug resistance in both human and veterinary medicine, and the problem of drug residues in milk and meat. In addition, they have a great economic impact, by minimizing the amounts of discarded milk and the number of culled calves in dairy herds. Nanotechnology was also applied to develop pet care products and hygienic articles. The present review discusses the advantage of using nanomaterials compared to their counterparts, the various classes of nanoparticles, and illustrates the applications and the role of nanotechnology in the field of veterinary medicine.

Controlling the Length of Microtubules by Manipulating Their Polymerization Condition

Microtubule is a cytoskeletal protein filament that holds great promise for various applications in nanotechnology. However, controlling the length of microtubules has been a challenging task. Here we show that the length of microtubules can be easily controlled by manipulating the polymerization condition. The number of polymerization stage and time of polymerization under controlled condition are found to be useful in regulating the length of microtubules. This work is important for widening the applications of microtubules in nanotechnology, such as nano-shuttle, success of which greatly relies on the length of microtubules employed.

Studies on the Anti-Oxidative Function of trans-Cinnamaldehyde-Included β-Cyclodextrin Complex.

trans-Cinnamaldehyde (tCIN), an active compound found in cinnamon, is well known for its antioxidant, anticancer, and anti-inflammatory activities. The β-cyclodextrin (β-CD) oligomer has been used for a variety of applications in nanotechnology, including pharmaceutical and cosmetic applications. Here, we aimed to evaluate the anti-inflammatory and antioxidant effects of tCIN self-included in β-CD complexes (CIs) in lipopolysaccharide (LPS)-treated murine RAW 264.7 macrophages. RAW 264.7 macrophages were treated with increasing concentrations of β-CD, tCIN, or CIs for different times. β-CD alone did not affect the production of nitric oxide (NO) or reactive oxygen species (ROS). However, both tCIN and CI significantly reduced NO and ROS production. Thus, CIs may have strong anti-inflammatory and antioxidant effects, similar to those of tCIN when used alone.

STRATEGI PENGEMBANGAN NANOTEKNOLOGI DALAM RANGKA PENINGKATAN DAYA SAING INDUSTRI PERTANIAN NASIONAL DENGAN MENGGUNAKAN SWOT-ANP

Nanotechnology is believed to give a significant added value to agricultural industry. Various applications of nanotechnology provide opportunities for improving the global competitiveness of agricultural industry. This study aims to assess nanotechnology development strategy at the national agricultural industry by using quantitative SWOT method and ANP in BOCR (benefit, opportunity, cost, risk) perspective. The results from these two approaches were then compared. There were four stages of research procedure that consists of 1) analyzing agricultural industries that apply nanotechnology using quantitative SWOT, 2) formulating nanotechnology development strategy in the TOWS matrix quantitatively, 3) determining strategy alternative for developing nanotechnology on agricultural industry with ANP in BOCR perspective and 4) assessing comparatively weight value of each strategy alternative using quantitative SWOT and ANP in BOCR perspective. Data was collected by conducting FGD (group discussion forum) for 20 participants and questionnaire to 10 experts in the field of food chemistry, agriculture, nanotechnology and policy. Results show that in formulation of nanotechnology development strategy on national agriculture industry, aspects of opportunities and positive impact are taken to account more than that risk and economic aspects. ANP results indicate that nanotechnology development on national agricultural industry is still in the early stage where strategy that leads to increased mastery of technology is payed more intention than the implementation of research result itself, socialization of nanotechnology safety and governance of policies. Strategy formulation done by ANP in BOCR perspective is slightly difference than that of done by quantitative SWOT method which uses only independent variables. The result of this study can be used as a reference for stake holders for strategic decision making in relation to improving competitiveness of national agricultural industry through the development of nanotechnology.

Is DNA Branch Migration a One-Dimensional Random Walk?

Toehold-mediated DNA strand displacement is a ubiquitous tool used in various applications of nanotechnology including biosensors, DNA walkers, and DNA computing. More fundamentally, DNA strand displacement is a crucial step in homologous recombination and DNA repair. The reaction involves 3 strands of DNA whereby initially 2 form a partially bound complementary duplex. The third strand, which is longer and entirely complementary, is thought to first bind to the toehold, the unpaired region of partially bound duplex. It has long been thought that the 2 complementary strands compete for base pairs at a junction or “branch” which undergoes a one-dimensional random walk until one of the strands is completely displaced. However, direct experimental proof of this concept has never been demonstrated. In this study, we investigate the kinetics of three-strand branch migration to address the suitability of the random walk model. We used single-molecule FRET and fluorescence dequenching to construct the full distribution of displacement times. We explore the effects of salt, sequence, and length on displacement kinetics to illuminate the underlying mechanism of DNA strand displacement. Our results show that the random walk model cannot adequately describe the observed kinetics of DNA strand displacement and implicate cooperativity in branch migration.

Observation of Adsorption Process of Single Stranded DNA to Single-Walled Carbon Nanotubes Surfaces by Fluorescence Quenching

Single walled carbon nanotubes (SWNTs) are one of the promising nanomaterials for various applications in nanotechnology. In biomedical fields, hybrids of DNA and SWNT (DNA-SWNT hybrids) are expected to be attractive nanodevices for drug delivery and DNA sensors. For preparing DNA-SWNT hybrids, mixture of SWNT and DNA solutions are prepared via sonication. Although DNA-SWNT hybridization techniques have been established, the diverse sonication conditions in every paper may affect structures of DNA-SWNT hybrids. Here we report a method of monitoring adsorption process of DNA to SWNT surfaces using fluorescent labeled single-stranded DNA (Fluor-ssDNA). It is known that fluorescent emission of fluorescent dyes is quenched when the dye is adsorbed on SWNT surfaces. Using this unique quenching phenomenon, we evaluated adsorption process of Fluor-ssDNA on SWNT surfaces. In the experiments, 0.25 mg of SWNT powder, 50 uL of Fluor-ssDNA solution (1.0 mg/mL in tris (hydroxymethyl aminomethane buffer solution, 200mM, pH 7.5)), and 450 uL of the buffer were mixed, and then sonicated under three different sonication conditions as follows: probe type with amplitude 60% of 130 W (P60), probe type with amplitude 20% of 130 W (P20), and bath type with 80 W (B80). In order to monitor the adsorption process, samples were characterized by fluorescent spectroscopy and atomic force microscopy. In the case of P60, fluorescent intensity of Fluor-ssDNA decreased 98% within 2 min. This suggests that most of Fluor-ssDNA rapidly adsorbed on SWNT surfaces. However, AFM images demonstrated that it took more time to form mono-dispersed DNA-SWNT hybrids. In the case of P20 and B80, 30 min was needed for 98% quenching. In addition, reproducibility of the B80 data was much higher than that of P20. This is an advantage of bath type sonicator.

Using Planar Phi29 pRNA Three-Way Junction to Control Size and Shape of RNA Nanoparticles for Biodistribution Profiling in Mice.

RNA is rapidly emerging as a versatile building block for nanoparticle assembly due to its simplicity in base pairing, while exhibiting diversity in function such as enzymatic activity similar to some proteins. Recent advances in RNA nanotechnology have generated significant interests in applying RNA nanoparticles for various applications in nanotechnology and nanomedicine. In particular, assessing the effect of size and shape on cell entry and intracellular trafficking as well as in vivo biodistribution of nanoparticles is challenging due to the lack of nanoparticles rich in structure while varying in size and shape. RNA nanotechnology exemplified by the packaging RNA (pRNA) of bacteriophage phi29 DNA packaging motor has provided a different prospect in nanoparticle designs. Of note, there is a robust three-way junction (3WJ) motif in pRNA which can serve as an adaptable scaffold to construct thermodynamically stable 2D planar and 3D globular RNA architectures with tunable shapes and sizes, and harboring various targeting, therapeutic, and imaging modules. This chapter focuses on the methods for constructing pRNA-3WJ based nanoparticles with controllable sizes and shapes, and assessment of their biodistribution profiles in cancer mouse models after systemic injection and ocular mouse models following subconjunctival injection.

Spatially Multiplexed Micro-Spectrophotometry in Bright Field Mode for Thin Film Characterization.

Thickness characterization of thin films is of primary importance in a variety of nanotechnology applications, either in the semiconductor industry, quality control in nanofabrication processes or engineering of nanoelectromechanical systems (NEMS) because small thickness variability can strongly compromise the device performance. Here, we present an alternative optical method in bright field mode called Spatially Multiplexed Micro-Spectrophotometry that allows rapid and non-destructive characterization of thin films over areas of mm2 and with 1 μm of lateral resolution. We demonstrate an accuracy of 0.1% in the thickness characterization through measurements performed on four microcantilevers that expand an area of 1.8 mm2 in one minute of analysis time. The measured thickness variation in the range of few tens of nm translates into a mechanical variability that produces an error of up to 2% in the response of the studied devices when they are used to measure surface stress variations.

THE INVESTIGATION OF NANOTECHNOLOGY SOLUTIONS TO DEAL WITH POLLUTANTS IN THE ENVIRONMENT AND DRINKING WATER TREATMENT

Due to the increase of concentrations of fine-grained materials, nitrogenous compounds, organic and mineral material and heavy metals, conventional methods do not meet treatment pond needs and relatively new treatment methods are required. With the development of nanotechnology, new nano materials, nano particles and nano catalysts are developed that havea very high efficiency in treatment pond. Advanced and modern technology methods such as nano filters (for industrial wastewater treatment), nano powders (for treating automobile exhaust gases), nanotubes (for storing a clean fuel of hydrogen) and nano catalysts are important in protecting the environment. Various applications of nanotechnology are as follow: 1. Using nano structure particles in treating pollutants, 2. removing color from drinking water, 3. water desalination, 4. Nano polymers, 5. using nanoparticles in treating wastewater, 6.nanofilters and 7. Removing arsenic from water