Day 2 :
Keynote Forum
Nikolaus Stolterfoht
Helmholtz-Zentrum Berlin, Germany
Keynote: Guiding of highly charged ions through nanocapillaries in insulating materials: Milestones in experiments and simulations
Time : 09:30-10:15
Biography:
Nikolaus Stolterfoht started his career in the 70’s at the Hahn-Meitner Institute in Berlin, which is one of the national laboratories of Germany. He was the Head of a research group working in the field of atomic collisions with gaseous atoms and solids. He was the Professor at the University of Caen, France. Later, he re-joined to the Helmholtz-Zentrum Berlin.
Abstract:
After the first observation that keV ions are guided through insulating nanocapillaries, the topic has received considerable attention during the past decade. These capillaries are nanotubes with a diameter of about 100 nm and a length of about 10 µm. The essential property of the capillary guiding is a self-organizing process, which governs the charge deposition inside the capillaries. With increasing deposition of the ions, the charge patch increases until the electrostatic field is large enough to deflect the ions. At equilibrium, the ions are guided maintaining their incident charge state. Milestones of the field concerning experiments and simulations are presented in accordance with a recent review over the field of capillary guiding. Experiments are described giving emphasis to the guiding of highly charged ions in the keV energy range. Recent experiments with a single straight macrocapillary are treated allowing for the control of conductivity by changing the temperature of the material. Single tapered capillaries are discussed involving an enhancement of the beam density and the production of a microbeam for biological applications. These studies have motivated several groups devoting efforts to the production of a beam with diameter of the submicron scale. Apart from the experimental studies, theoretical concepts of the capillary guiding are discussed. Calculations using a drift model for trajectories and charge distributions for 4.5-keV Ar7+ incident under 0° and 1° into a conical microcapillary were shown in Figure-1. The simulations show that the density of the transmitted ions is enhanced by a factor as large as 4. These results are of importance for the biological applications mentioned. Altogether, it is elucidated that capillary guiding involves several novel phenomena whose understanding has made essential progress.
Keynote Forum
Somnath Bhattacharyya
University of the Witwatersrand, South Africa
Keynote: Quantum technology based on superconductivity in boron-doped nanocrystalline diamond films
Time : 10:15-11:00
Biography:
Somnath Bhattacharyya is a Professor in the School of Physics at the University of the Witwatersrand, Johannesburg, South Africa. After completing his Doctoral degree from the Indian Institute of Science, Bangalore, he has worked as a Researcher in the USA, Germany and England. Later, he established his new research group the Nano-Scale Transport Physics Laboratory at the University of the Witwatersrand. His major interest is in the transport properties of carbon and has achievements including the demonstration of resonant tunnel devices based on amorphous carbon, gigahertz transport in carbon devices, n-type doping of nanocrystalline diamond and developing theoretical models for transport in disordered carbon. He has published 04 book chapters and over 70 papers in peer reviewed journals.
Abstract:
Diamond is considered as the ideal material for making quantum devices since the lattice constant does not change even in extreme conditions. The ways one can construct qubits in diamond are creating nitrogen vacancy centers and superconducting quantum interference devices. Although the later one has not realized yet, we find there are some similarities between two cases based on the recently developed concept of topological nature of diamond nitrogen vacancy centers and the transport property measurements in the boron-doped nanocrystalline diamond films. Over decade superconductivity in boron-doped diamond initiated intense research due to possible unconventional superconducting state. This can be established in two ways namely introducing graphitic carbon layers which can have a chiral nature and incorporating excess boron atoms in diamond lattice which can form a spin triplet state. Having understood a non-s wave character of these diamond films we are searching for p-wave (odd frequency) character which is related to topologically protected phases. This work will potentially motivate us for a deeper study into the application of this material for a new class of topological qubit which has the capability of revolutionizing the field of quantum computing. The theoretically predicted non-Abelian gauge field and associated Berry phase in diamond system is to be realized experimentally. In this talk we elaborate the novel heterostructures of superconducting nanodiamond films and some exotic transport properties that can be useful for developing topological qubits. Some quantum device concepts combining nitrogen vacancy center and boron doped superconducting diamond are thus discussed.
Keynote Forum
Rafael Popper
VTT Technical Research Centre of Finland, Finland
Keynote: Developing a sustainable circular economy strategy for electric mobility: Assessing the role of Li-ion battery technology
Time : 11:15-12:00
Biography:
Rafael Popper (PhD) is a Principal Scientist in Foresight, Organizational Dynamics and Systemic Change at VTT Technical Research Centre of Finland and Research Fellow at the Manchester Institute of Innovation Research of the University of Manchester. He is the Director of Executive Education in Foresight and Horizon Scanning at the Alliance Manchester Business School and Innovation Director and CEO of Futures Diamond Ltd (UK and Czech Republic). He has also worked at United Nations Industrial Development Organization (UNIDO) and as Consultant for the European Commission, World Bank and other international, governmental and business organizations in Europe, Latin America, Africa, Asia and Australia.
Abstract:
Due to climate change as well as the growing capacity of new storage media for electric power, electric mobility represents a future vision for individual mobility on an environmentally friendly basis. We present a way to develop a future vision about this kind of economy and the elements its progression requires. We assess critical issues, such as barriers, drivers, opportunities and threats, for electric engine system development and prioritize those issues from a set of selected innovations and development trends. Following the critical issue assessment and analysis, we identify potential key aspects affecting the context, people, process and impact of electric mobility management dimensions. Here, context refers to critical factors clustered around potential space for innovation; capacity to anticipate, strategize and overcome gaps in the innovation curve; resources emphasizing the need for healthy combinations of skills, finance, location, markets, etc., and mobilization of relevant stakeholders including business, research and education, civil society and government actors. People dimension consists of critical factors shaping the activities of the actors involved in activities and decisions influencing electric mobility. Moreover, transforming electric mobility is a complex, participatory and multifaceted process. We can divide process-related critical factors into two broader sets of key aspects: Catalysts, contributing to the initiation, development and implementation of electric mobility and fosterers, including factors that further support the implementation and diffusion phases of electric mobility innovations. The impact dimension refers to positive changes in the socio-technical system that lead to positive environmental, social, economic, government and infrastructure transformations without compromising the needs of future generations. Through systematic bibliometric and patent analyses we show that lithium-ion (Li-ion) battery has been a key enabling technology for electric mobility and future (electric) engine systems. However, a growing number of researchers are trying to shift away from conventional Li-ion battery technology and apply nanotechnology to other energy storage devices in order to make them more cost competitive and influence superior performance as compared to Li-ion batteries. A careful analysis and evaluation of the advantages and disadvantages of these approaches is therefore indispensable.
Keynote Forum
Giuseppe Mucci
Bioscience Clinic ,UAE
Keynote: Stem Cells: The new frontier of drugs
Time : 12:00-12:45
Biography:
Giuseppe Mucci has graduated in Movement Science at Faculty of Medicine in Urbino, Italy. He is a Professor of Bio-Economy at the University of Lugano, Switzerland and Advisory Board Member of the University of Roma Tor Vergata. He has established Bioscience Institute in San Marino, Italy in 2007 and Bioscience Clinic in Dubai, UAE in 2013.
Abstract:
Scientific innovations of the last year had pushed stem cells as an alternative therapy to drug and synthetic material. Several recent studies have demonstrated the effectiveness of these cells in cancer therapies; indeed, some researches had established the significant biological safety of adipose derived stem cells and more important procedures exploiting stem cells, during the expansion process, do not need products extracted from animal (bovine fetal serum): this assures a higher level of compliance with GMP quality standards. Platelet lysate is the medium that, if introduced in the biological culture, other than provide a safer final product, results in a significant increase of the proliferation process, hence a reduction of the time of cultivation (almost 50%). Moreover, using stem cells, cell proliferation increased 10 times more than precedent culture techniques. A safer and more effective product is the results of the use of adipose derived stem cells. Moreover, also production costs are reduced which had resulted in more cost-effective use of autologous expanded ADSC’s for patients. An important clinical study conducted by the University of Copenhagen had demonstrated the effectiveness of adipose derived stem cells in soft tissue augmentation making it a suitable alternative to the use of implants or fillers for body shaping or face contour. Furthermore, a clinical study from most important European universities in the field of orthopedics funded by the European Union (within the 7th Framework Program) analyzed the application of the stem cells in the treatment of cartilage degeneration (osteoarthritis). This clinical trial (ADIPOA) lasted 54 months and it demonstrated the safety and effectiveness of stem cells in the treatment of osteoarthritis. Moreover, it also highlights the ideal dosage to cure this disease. Stem cells are an alternative product to botulinum toxin, hyaluronic acid, polylactic acid and anti-inflammatory and immunomodulatory medicines.
Keynote Forum
Basma El Zein
University of Business and Technology, KSA
Keynote: Nanomaterials for 3rd generation sensitized solar cells
Time : 13:45-14:45
Biography:
Basma El Zein is the Dean of Scientific Research at UBT. She has nearly 18 years of experience in academic and research institutions. She was a Research Scientist at King Abdullah University of Science and Technology (KAUST) and an Associate Researcher at IEMN, Lille, France. She is a Senior Member of IEEE, Member of ACS, MRS, SPIE and ECS. She has been selected as winner of Albert Nelson Life Achievement Award by Marquis Who’s Who, 2017 and Solar Pioneer by MESIA, 2015. Her research interests include working on nanostructures for third generation eco-green solar cells, energy harvesting and energy storage. She is exploring new materials perovskite to be used as light absorber for solid state sensitized solar cells. She is a Reviewer in many international, peer-reviewed journals, the chair or co-chair and on the committee of different international conferences, has published many international journals and had one patent.
Abstract:
Nano-materials are considered as building block for many optoelectronic devices. They differ from bulk counterpart in the size, characteristic and offer new opportunities to be employed in various applications. Zero dimensional (0D) and one dimensional (1D) nanostructures have attracted lots of attention in solar energy harvesting, conversion and storage, owing to their unique physical and chemical properties. Nano-materials offer many advantages in energy conversion specifically in solar cells. These solar cells, depends on the physical interaction between nanomaterials or chemical reaction at the surface or interface of the nanomaterials. In this presentation, we will discuss the zero and one dimensional nanostructures and the role they play in increasing the conversion efficiency of solar cells, taking in consideration the materials to be used to meet the main objective of developing an eco-green solar cell with high conversion efficiency.
- Materials Science and Nanotechnology | Applications of Nanotechnology | Nanomedicine | Molecular Nanotechnology | Nano Chemistry | Nano Bio Materials
Location: Salon VII
Chair
M Vlcek
University of Pardubice, Czech Republic
Co-Chair
Mike S Scurrell
University of South Africa, South Africa
Session Introduction
Basma El Zein
University of Business and Technology, KSA
Title: Nanomaterials for 3rd generation sensitized solar cells
Time : 13:45-14:15
Biography:
Basma El Zein is the Dean of Scientific Research at UBT. She has nearly 18 years of experience in academic and research institutions. She was a Research Scientist at King Abdullah University of Science and Technology (KAUST) and an Associate Researcher at IEMN, Lille, France. She is a Senior Member of IEEE, Member of ACS, MRS, SPIE and ECS. She has been selected as winner of Albert Nelson Life Achievement Award by Marquis Who’s Who, 2017 and Solar Pioneer by MESIA, 2015. Her research interests include working on nanostructures for third generation eco-green solar cells, energy harvesting and energy storage. She is exploring new materials perovskite to be used as light absorber for solid state sensitized solar cells. She is a Reviewer in many international, peer-reviewed journals, the chair or co-chair and on the committee of different international conferences, has published many international journals and had one patent.
Abstract:
Nano-materials are considered as building block for many optoelectronic devices. They differ from bulk counterpart in the size, characteristic and offer new opportunities to be employed in various applications. Zero dimensional (0D) and one dimensional (1D) nanostructures have attracted lots of attention in solar energy harvesting, conversion and storage, owing to their unique physical and chemical properties. Nano-materials offer many advantages in energy conversion specifically in solar cells. These solar cells, depends on the physical interaction between nanomaterials or chemical reaction at the surface or interface of the nanomaterials. In this presentation, we will discuss the zero and one dimensional nanostructures and the role they play in increasing the conversion efficiency of solar cells, taking in consideration the materials to be used to meet the main objective of developing an eco-green solar cell with high conversion efficiency.
Ali Trabolsi
New York University Abu Dhabi, UAE
Title: Calix[n]arene based multi-functional porous materials for environmental applications
Time : 14:45-15:15
Biography:
Ali Trabolsi has received his BSc degree in Chemistry from the Lebanese University in Beirut. He has received his Master’s degree in Analytical Chemistry and also completed his PhD. Later he joined KAUST in Saudi Arabia as a Research Scientist in the Membrane Center. Presently, he is an Assistant Professor at New York University Abu Dhabi.
Abstract:
Owing to the increasing level of attention focused on the preservation of the environment, there is a growing need for novel multi-functional materials that can meet the increasing demands from society on water resources and pollution remediation. Porous organic polymers composed of light elements that possess high specific surface areas, large pore volume and multiple functionalities are good candidate to fulfill the requirements. In particular, porous covalent organic polymers (COPs) are a promising class because of their ultrahigh hydrothermal stabilities and high yielding synthetic polymer chemistry. Calix[n]arenes (n=4, 6, 8) have long been recognized as versatile supramolecular scaffolds, however, many previous studies report the syntheses and properties of monomeric calixarenes, fewer describe their incorporation into polymers and in most of these, the macrocycles serve only as side-chain pendants. Very recently, we reported the successful synthesis of a first-in-class calixarene-based porous covalent polymer and tested its adsorption ability toward oil and organic solvents. Building on this exciting finding, we synthesized library of porous materials having different calix[n]arene homologs (n=4, 6, 8) as their backbone (BET surface area ranged from 500 to 1000 m2 g-1). In addition, these materials found to be super hydrophobic and therefore, we successfully implemented these materials for multiple applications including oil spill recovery, toxic dyes and micropollutants removal, iodine vapor enrichment and selective gas adsorption and separation. The high efficiency and ease of implementation of the polymer demonstrate the advantages of incorporating the calixarene moiety within a functional material and bode well for the development of calixarene-based materials for environmental applications.
Haythem Suliman Basheer
University of Bahri, Sudan
Title: ZnO synthesis using wet chemical growth with various nanostructures
Time : 15:15-15:45
Biography:
Haythem Suliman Basheer has obtained his MSc in Nanoscience and Nanotechnology. He has been teaching at University of Bahri, Faculty of Applied and Industrial Sciences and his research interest is in nanotechnology especially in clean renewable energy (solar cell) to improve its efficiency and water treatment and purification and desalination.
Abstract:
In this work, zinc oxide nanostructures (NSs) are formed by aqueous chemical growth using equal molar quantities of zinc acetate dehydrate and Hexamethylenetetramines (HMTA) (C6H12N4, 99.5%) at low temperature on Aluminum substrate. The surface morphology of the ZnO (NSs) was characterized using Scanning Electron Microscope (SEM) which showed the change in shape. Pictures of ZnO nanobelts, nanotubes and nanoroses were achieved with the average dimensions ranging between 100 to 300 nm. EDX analysis was used to confirm ZnO purity and UV visible absorption spectrum of ZnO was determined and maximum absorption wavelength was located at 410.67 nm. The calculated band gab was found to be 3.04 eV. XRD was used to confirm the crystallinity of ZnO (NSs).
Dongmyung Oh
National University of Singapore, Singapore
Title: Competition for Grb2 recruitment between EphA2 and EGFR during ligand activation
Time : 16:00-16:30
Biography:
Dongmyung Oh has expertise in single molecule biophysics in live cell imaging. In a recent study of receptor tyrosine singling, he found that the rebinding mechanism by which a cytosolic signaling molecules bind/unbind and rebind to receptor.
Abstract:
Activation of EphA2 and EGFR receptor tyrosine kinases (RTKs) is initiated immediately after binding of their respective ligands, recruiting a variety of downstream signaling proteins and ultimately triggering a diverse range of biological outcomes. Although EphA2 and EGFR respond to distinct ligands (ephrinA1 and EGF, respectively) and trigger distinct responses, they also share key proximal signaling molecules. One such molecule is Grb2, which is an adaptor protein recruited to phosphorylated tyrosine residues and responsible for the recruitment of the Ras activator, SOS. How such receptor triggered signaling activities retain the identity of the triggering receptor and how (or if) different receptors may synergize or compete remains largely unknown. Here, we monitor Grb2 recruitment to ligand-activated receptors in a live cell system in which EphA2 and EGFR are spatially segregated, thus allowing unambiguous distinction of which receptor signaling complex each Grb2 molecule is binding. Results reveal a competitive effect by which, one receptor type can influence the signaling activity of the other remotely. Detailed analysis of Grb2 membrane recruitment kinetics reveals distinct differences between Grb2 recruitment to activated EphA2 clusters and clusters of activated EGFR. Consequences of this type of molecular competition for adaptor proteins in the overall context of signal transduction will be discussed.
Bhaskar Das
University of Nebraska, USA
Title: Unusual ferromagnetism at nanoscale due to surface-spin-reorientation
Time : 16:00-16:30
Biography:
Bhaskar Das is a post-doctoral scientist at the Ames Laboratory of United States Department of Energy (US-DOE). He did his Ph.D. at the Nebraska Center for Materials and Nanoscience of University of Nebraska-Lincoln, Department of Physics and Astronomy. His area of research involves physics of magnetism, nanoscience, materials physics and spintronics. Currently he is working at the US-DOE lab in the project related to magnetism for renewable energy and device technologies.
Abstract:
Mn-based silicides are attractive from the viewpoints of fundamental science and potential applications in spintronics, owing to their exotic spin textures and unique crystal structures. However, bulk alloys show only weak low-temperature magnetic ordering and this inhibits their practical room-temperature applications. Our recent report shows that magnetic nanoclusters exhibit entirely different magnetic properties from the corresponding bulk alloys due to nanoscale effects. In this study, we report the synthesis of novel Mn5Si3 nanoclusters using a gas-aggregation type cluster-deposition method and show unusual ferromagnetism experimentally and by first-principle DFT calculations, in a sharp contrast to antiferromagnetic behavior shown by bulk alloys below 100 K. TEM studies show that Mn5Si3 nanoclusters are monodispersed with an average size d » 8.7 nm and an rms standard deviation σ/d»0.1. The nanoclusters are also single crystalline and form the D88-type hexagonal structure as shown by HRTEM (Figure-1a) and FFT (Figure-1b) images, respectively. The nanoclusters show appreciable coercivities (Hc=900 Oe at 3 K and 450 Oe at 300 K) and high saturation magnetic polarization (Js=12.5 kG at 3 K and 10.5 kG at 300 K) [Figure-1(c)] with a high Curie temperature (Tc≈590 K) [Figure-1(d)]. The fitting of magnetization curve at high-field region (35-70 kOe) using the law-of-approach to saturation method yields an appreciable magneto crystalline anisotropy constant K1≈12 Mergs/cm3. Thus, easy-axes of the nanoclusters were successfully aligned using an external magnetic field prior to deposition, which results in improved Hc (1700 Oe at 3 K and 600 Oe at 300 K). The nanocluster magnetic properties are mainly due to the large surface spin-polarization (m=3.3 µB/Mn) that subsequently spin-polarizes the nanocluster-core (m=0.9 µB/Mn), as revealed by the DFT simulations.
Peng-Sheng Wei
National Sun Yat-Sen University, Taiwan
Title: The effects of wave characteristics on energy generation during additive manufacturing
Time : 16:30-16:50
Biography:
Peng-Sheng Wei has received his PhD in Mechanical Engineering Department from University of California, Davis. He has been a Professor in the Department of Mechanical and Electro-Mechanical Engineering of National Sun Yat-sen University, Taiwan. He has contributed in advancing the understanding of and to the applications of electron and laser beam, plasma and resistance welding through theoretical analyses coupled with verification experiments. He has published more than 80 SCI journal papers. He has been the Xi-Wan Chair Professor of NSYSU and Invited Distinguished Professor in the Beijing University of Technology, China.
Abstract:
A systematical investigation of energy generation responsible for heating and melting during selective laser melting or selective laser sintering in additive manufacturing with a pulsed laser is studied. A surface Plasmon on a rough or grating metal surface can be excited by an incident laser beam in a TM mode. The surface plasma wave is an electromagnetic wave that propagates at the boundary between two media, leading to a concentrated and distributed energy generation on the surface. In this study, energy generated is composed of resistive, dielectric and magnetic losses. Distributions of different modes of energy generated for different frequencies and widths of laser beam irradiating on particles on a surface are presented. Heating and melting during additive manufacturing are, therefore, revealed. Figure-1 shows high energy generation or divergence of Poynting vector occurs near the peak and surface of particles on a surface for different radii of incident electromagnetic wave. Electrical field propagates in radial directions while energy generation decreases, provided that the radius of incident electromagnetic wave decreases.
Martin Caldarola
Leiden University, Netherlands
Title: Single-molecule fluorescence enhancement by gold nanorods: An application to electrochemistry
Time : 16:50-17:10
Biography:
Martin Caldarola is a Postdoctoral Researcher at the Single-Molecule Optics group, Leiden University, Netherlands. He holds a PhD in Physics from the University of Buenos Aires and his expertise is in the field of nanophotonics. His research interest is focused on light-matter interactions, specifically the interaction between single-molecules and nanostructures, including fluorescence enhancement and nonlinear effects in the nanoscale.
Abstract:
Electrochemical (EC) reactions are of crucial importance in diverse fields of nanoscience. Methylene Blue (MB) is well-known redox indicator that can be used as nanoscale probe of the electrochemical environment. With this aim we studied the fluorescence redox-induced blinking of single MB molecules: this molecule is fluorescent in the oxidized state and non-fluorescent in the reduced state. Due to the low fluorescence yield of this molecule Single Molecule (SM) optical sensitivity was achieved employing the high fluorescence enhancement factors provided by individual gold nanorods for weak red fluorophores. Our experimental approach combined single-molecule sensitive confocal setup with an electrochemical cell which allowed the fluorescence readout for an externally-controlled oxidation state of the MB molecule. We work with immobilized MB molecules on a glass surface and we observe the molecules that are enhanced near the tip of the nanorod. We could study the same MB molecule at different electrochemical potentials and we observed that the fluorescence blinking responds to the EC potential change. We performed this type of measurement for several single molecules and from the Nernst Equation we extracted the mid-point potential value, the potential where the molecule spends half of the time in the reduced (dark) state and half of the time in the oxidized state (fluorescent). We found a small dispersion for this value of about 21 mV in a mean value of 78 mV. In conclusion, we accessed the electrochemical properties of methylene blue at single-molecule level using an optical method based on fluorescence enhancement by individual gold nanorods.
- Poster presentation
Location: Salon VII
Session Introduction
T Cele
University of South Africa, South Africa
Title: PGM nanoparticles and hybrid nanocomposites by gamma radiolysis/EISA
Time : 17:10-17:30
Biography:
Takalani Cele has received her MSc in Physical Science from University of the Western Cape, South Africa. She is currently pursuing PhD in Nanotechnology at University of South Africa. Her research interest is PGMs nanoparticles by radiolysis, jointly supported by iThemba Laboratory for Accelerator Based Science in South Africa and Université du Maine, Le Mans, France. She is also working on other projects in the Department of Trade and Industry in Innovation and Technology unit.
Abstract:
The multi-functional Platinum Group Metals (PGMs) pure and hybrid nanostructures are based on a biomimicking approach. Marine organisms like diatoms and radiolaria provide material scientists with many examples microstructures are formed by biomineralization a templated self-assembly process in which pre-organized organic surfaces regulate the nucleation, growth, morphology and orientation of inorganic crystals. Recently, various synthetic pathways that mimic aspects of biomineralization have been explored to produce patterned ceramic materials, among which the so-called EISA and EISA templating processes. This research project focuses on the development of pure and hybrid advanced 1-, 2- and/or 3-dimensional PGMs nanocomposites for multi-functional technological applications by a versatile novel hybrid nanotechnology-nuclear process: Radiolysis and Evaporation Induced Self Assembly (EISA). Pt solution of different concentration was prepared from K2PtCl4. The effect of irradiation on Pt4+ solutions with different concentrations irradiated at a certain dose was shown. The big black particles that are fairly agglomerated were spotted when the concentration is above 5×10-3 M. The UV-Vis spectrum of Pt of different concentrations shows a strong absorption peak at the wavelength 261 nm after irradiation, which indicates the presence of platinum nanoparticles. Furthermore, XRD and HRTEM images also confirmed the presence of the nanoparticles produced by radiolysis.
Mamta Bhardwaj
Sant Longowal Institute of Engineering & Technology, India
Title: Synthesis of starch nanoparticles by acid hydrolysis alone and coupled with other technique and their subsequent characterization and utilization
Time : 17:30-17:50
Biography:
Mamta Bhardwaj has obtained her Bachelor’s degree in Biotechnology, Masters in Food Engineering & Technology and is presently a Doctoral student and an INSPIRE Fellow at Sant Longowal Institute of Engineering & Technology, India. Her current research interests include starch and its nanoparticles and rheology of food materials, particularly the dynamic mechanical analysis.
Abstract:
Starch is one of the most abundant biopolymer extracted from plants in the form of micro-granules. Due to fascinating properties of being non-toxic, non-irritant, low-cost, ease of modification and versatile use, etc., makes starch a promising candidate to prepare nanoparticles. Starch nanoparticles already attract great interest because of their wide application in food, cosmetics, medicines as well as various composites. Various botanical sources are available for extraction of starch nanoparticles facilitating nanoparticles with a range of amylose content, shape, viscosity in suspension and thermal resistance. Starch nanoparticles can be synthesized by both physical and chemical methods. In the present study, starch nanoparticles were synthesized from two varieties of Pearl millet (HHB67 and ProAgro 9444) by acid hydrolysis and acid hydrolysis coupled with ultrasonication. Acid hydrolysis at 3.2 M H2SO4 and 40 oC for 5 days resulted in starch nanoparticles in the range of 40-60 nm whereas acid hydrolysis for 2 days coupled with ultrasonication resulted in 20-30 nm particle size. Among the two varieties HHB67 gave nanoparticles with smaller size than ProAgro 9444 due to more amylopectin content viz., 85% amylopectin in HHB67 and 79% in ProAgro 9444. Morphological and crystalline structure was analyzed by scanning electron microscopy and XRD respectively. The results revealed that nanoparticles possess A-type granular structure as obtained for the crystalline structure of original starch varieties. Besides the nanometric size, methods and varieties showed significant difference in solubility, hygroscopicity and paste clarity. Dynamic mechanical analysis was studied to obtain temperature and amplitude sweep data. Nanoparticles obtained by acid hydrolysis and acid hydrolysis coupled with ultrasonication can be used in bio-nanocomposites.