1Department of Chemistry, National Taiwan University, Taiwan
2Institute of Atomic and Molecular Sciences, Academia Sinica, Taiwan
3Nano Science and Technology Program and Molecular Science and Technology Program, Taiwan
3International Graduate Program, Academia Sinica, Taiwan
4Department of Physics, National Central University, Taiwan
5Center for Condensed Matter Sciences, National Taiwan University, Taiwan
In this paper, we report the optoelectronic properties of multi-layered GeS nanosheets (~28 nm thick)-based field-effect transistors (called GeS-FETs). The multi-layered GeS-FETs exhibit remarkably high photo responsivity of Rλ ~ 206 AW-1under illumination of1.5 µW/cm2 at λ = 633 nm, Vg = 0 V, and Vds = 10 V. The obtained Rλ ~ 206 AW-1 is excellent as compared with a GeSnanoribbon-based and the other family members of group IV-VI-based photodetectors in the two-dimensional (2D) realm, such as GeSe and SnS2. The gate-dependent photo responsivity of GeS-FETs was further measured to be able to reach Rλ ~655 AW-1operated at Vg = -80 V. Moreover, the multi-layered GeS photo detector holds high external quantum efficiency (EQE~4.0 × 104 %) and specific detectivity (D* ~ 2.35 × 1013 Jones). The measured D* is comparable to those of the advanced commercial Si- and InGaAs-based photo diodes. The GeS photodetector also shows an excellent long-term photoswitching stability with a response time of ~7ms over a long period of operation (>1 h). These extraordinary properties of high photo current generation, broad spectral range, fast response, and long-term stability make the GeS-FET photodetector a highly qualified candidate for future optoelectronic applications.
Keywords: Germanium sulfide, photo detector, photo responsivity, external quantum efficiency, specific detectivity
Biography:
U. Rajesh Kumar obtained his Bachelor of Technology in Biotechnology from Anna University (2008) and Master of Technology in Nanotechnology from Indian Institute of Technology Roorkee (2010). Later he joined the Nanoscale Materials and Bio-analytical Chemistry lab through Taiwan International Graduate Program (TIGP) offered by Academia Sinica to pursue his doctorate in Nanoscience and Nanotechnology under the supervision of Professor Yit-Tsong Chen. His current research interests are the fabrication of field-effect transistors using 2D layered materials and biosensing.
1 Riga Technical University, Latvia
2 TECHNION, Haifa, Israel
An electrical potential induced by the nanolayer of the biomaterial surface is able to control sorption of the microorganisms. Due to this both tissue regeneration and prevention of inflammations could be influenced, Burkholderia cepacia belonging to the inflammation factors. Solid and mesh Titanium are popular to fabricate implants. Their technological processing, annealing being one of them, provides electrical potential to the surface.
The report focuses solid and mesh Titanium (Ti) annealing to control the material surface electrical potential and Burkholderia cepacia sorption in vitro.
The solid and mesh Ti specimens (1x1x0.05 cm and 2x2x0.03 cm correspondingly) were prepared from the stripes and by foam technology respectively. The specimens were annealed at 600C during 2-4 h.
To identify the surface electrical potential the ultraviolet photoelectron spectroscopy was employed, the photoelectron work function (ϕ) was measured. The value of ϕ was directly connected to the surface electrical potential.
Burkholderia cepacia strain ATCC was grown on agar at room temperature. Next, the bacteria were scrapped off from broth, resuspended in phosphate saline buffer (PSB), washed off and centrifuged. Then the liquid was discarded and supernatant was resuspended in fresh PSB.
The concentration of bacteria increased on 5 and 45 %, correspondingly, if the solid and mesh Ti were annealed for 4 h. The Ti mesh in contrast with the solid Ti had a stronger influence on bacteria concentration.
The experiments demonstrates the Ti surface nanolayer electrical potential is a physical factor that induces Burkholderia cepacia concentration. To decrease it more negative surface electrical potential (the higher values of ϕ ) are preferable.
Acknowledgment: The research was supported by the Latvian Council of Sciences grant 491/2012
Biography:
Prof. Yuri Dekhtyar has the expertise to functionalize and characterize nanoobjects and nanostructured materials. He is the leader in prethreshold electron and exoelectron spectroscopy. He has around 450 publications, leaded a number of the international and national projects. Head of the Institute of Biomedical Engineering and Nanotechnologies of the Riga Technical University, Latvia; Latvian State Prize winner, full member of the Latvian Academy of Sciences.
1Liquidia Technologies, USA
2Envisia Therapeutics, USA
Background and Study: By leveraging techniques from the semiconductor industry, Liquidia developed a proprietary micro- and nanoparticle PRINT® platform, which has the ability to rapidly design and manufacture precisely engineered particles of virtually any size, shape, or composition at the tens of nanometer scale. PRINT® was used to fabricate uniform, monodisperse particles of various sizes and shapes to be used in different drug delivery applications. The following drug delivery applications and the effects of the PRINT platform will be discussed: sustained release of injectables, sustained release of dermal topicals, and the formulation of small molecules and biologics using the PRINT platform.
Results: The following results will be reviewed: the effect of size and shape on controlled and sustained release of APIs (biologics and small molecules), encapsulation of poorly soluble APIs using PRINT, and controlling PRINT particle forms (amorphous vs crystalline).
Conclusions: PRINT particles can incorporate small molecules (including difficult to formulate molecules) in a wide range of particle sizes and shapes to allow for improved properties such as enhancing dissolution profiles of poorly soluble drugs. Biologics such as Bevacizumab were encapsulated in PRINT particles of various sizes to fine tune monoclonal antibody release in vitro. Injectable PRINT particles were tuned to release API at different rates via various shapes and compositions.
Biography:
Donald Campbell was born in Louisiana. He is a graduate of the Louisiana School for Math, Science and the Arts. He attended Tulane University where he received a BSE in Biomedical Engineering. He also attended Case Western Reserve University where he received a MS in Biomedical Engineering. He currently lives in Durham, North Carolina and works at Liquidia Technologies located in Research Triangle Park, North Carolina.
School of Chemical Engineering, Yeungnam University, South Korea
Developing high-performance photoctalysts and photoelectrode with enhanced visible light harvesting properties are essential for practical visible light photocatalytic applications. Noble metal-free, highly visible light-active, elemental red phosphorus (RP) was prepared by a facile mechanical ball milling method, which is a reproducible, low cost and controllable synthesis process. The synthesis used inexpensive and abundant raw materials because most RP hybrids are based on expensive noble-metal. The novel milled RP showed significantly enhanced photocatalytic and photoelectrochemical performance with a lower charge transfer resistance than commercial RP under wide visible photoirradiation, making it a feasible alternative for photocatalytic applications.1
Biography:
Moo Hwan Cho is a Professor at School of Chemical Engineering, Yeungnam University, South Korea. He earned his MS in Chemical engineering from Korea Advanced Institute of Science and Technology in 1980 and received his PhD from Dept. of Chemical & Biochemical Engineering, Rutgers University, USA in 1988. His research area includes synthesis of metal nanoparticles and nanocomposite using electrochemically active biofilms, band gap engineering of semiconductor metal oxide nanoparticles for visible light photocatalysis, design, and development of electrode materials for supercapacitor and microbial fuel cells applications.
Division of Pharmaceutics, CSIR-Central Drug Research Institute, India
Leishmaniasis parasites are one of the intracellular protozoan parasites which reside primarily in host mononuclear phagocytes and usually lethal if untreated. Amphotericin B is a broad antimycotic agent and a highly antiparasitic one having severe nephrotoxicity and hematologic toxicity as the major limiting factors. These side effects led to extensive research in formulations in the form of liposomes, emulsions, lipid and polymeric nanoparticles which reduce the amount of free AmB in blood stream, thereby reducing its toxicity but their non-targetability and higher cost restricts their use to poorest to poor. Among all these colloidal carriers lipid nanoparticles have been extensively explored due to their ideal characteristics of better storage stability and higher drug loading which make it a promising candidate for novel drug delivery owing to its versatile nanotherapeutic applications. The nanoparticles surface was modified with a peptide sequence containing tuftsin. Tuftsin is known to stimulate the immune function of various cells, including macrophages (primarily), neutrophils, and monocytes. Surface modification with tuftsin was investigated on the basis of the fact that this tetrapeptide has been used for macrophage specific targeted delivery. The tuftsin modified nanoparticles could be used for effective delivery of biopharmaceuticals into the macrophages because of better accumulation in macrophage rich organs when compared with other colloidal systems due to their preferential phagocytosis. Therefore, we have developed tuftsin modified novel AmB lipid nanoconstructs. The main objective of this study was to develop and evaluate a new novel formulation of AmB as a cost effective and target oriented alternative. Various formulations were developed with the use of microfluidizer (optimized by varying pressure and number of cycles) and characterized for various parameters (particle size, zeta potential, % entrapment efficiency, morphology, stability, in vitro release and toxicity). The entrapment efficiency of AmB was achieved up to 88.4% for AmB-NLC and 83.5.3% for Tft-AmB-NLC with particle size 142±6.2nm and 162.6±4.4nm, and zeta potential of -28±1.6 mv and +32+1.3 mv, respectively. The optimized formulations were found stable for more than 3 months in terms of particle size and size distribution. The morphological characterization of the formulations was done using Transmission Electron Microscopy. The in vitro release profile of the AmB-NLC and Tft-AmB-NLC showed 62.6% and 60.2% drug release within 24 hours, respectively. The toxicity profile showed the permissible range of haemolysis and cytotoxicity.
The findings suggested that it would be preferable to deliver AmB through tuftsin anchored nanostructured lipid carriers.
Biography:
I, Priyanka Tripathi, am a full time Ph.D. student in Division of Pharmaceutics, CSIR-Central Drug Research Institute, Lucknow, India. I have passed B. Pharm. in 2006 and M. Pharm. (Pharmaceutics) in 2008 with honours (hold rank in university). I am also a post graduate diploma holder in drug regulatory affairs. I have published total 18 international research papers including 5 papers in first authorship. I have presented 9 oral, 8 poster and attended 5 national/international events. I am active member of AAPS, CRS and secretary of BRGʼs steering committee. I am CSIR-Senior Research Fellow in Division of Pharmaceutics, CSIR-CDRI, Lucknow, India from 02/04/2012 to till date and worked as Project Assistant Level-II in the same division from 11/06/2010 to 01/04/2012. I have also worked as Assistant Professor at SRNS College of Pharmacy, Gormi, India from 10th June 2006 to 22nd Oct. 2006 and from 30th Sept. 2008 to 24th May 2010.
1Department of Physics, Kanya Maha Vidhyalaya, India
2Dean, IKG Punjab Technical University Jalandhar, India
3Tata Institute of Fundamental Research, India
Au nanoparticles doped Bismuth borate glass was prepared by melt quenching technique. X-ray diffraction confirms the amorphous behaviour of the samples prepared. The prepared sample were studied by using UV-VIS and Fourier Infrared spectroscopic techniques. Optical band gap was calculated from transmission spectra using Mott and Davis model.
Biography:
He obtained his Doctorate (Ph.D.) from Guru Nanak Dev University, Amritsar, India in 1987. He was Visiting Faculty at Department of Physics, Grambling State University, Grambling, Louisiana, LA 71245, USA and worked as Visiting Scientist at International Centre for Theoretical Physics, Italy and Jozef Stephan Institute, Ljublijana, Yugoslavia.
He had completed sponsored research projects successfully on “Development of Lead based Ceramics for applications in Pyro-electric IR Sensors”, “On the transport properties of III -V Compound semi - conducting Thin Films”, “Development of GaxIn1-xSb thin films for Device applications” and “Development of LPE for semiconducting thin films”. He published book entitled, “Experiments in Materials Sciences” and was the Guest Editor for the special issue on Material Science: Trends and Future, published by Indian Journal of Engineering & Material Science.
Chemistry Department, Faculty of Science, King Abdulaziz University, Saudi Arabia
TiO2 nanospheres and Sn/TiO2 nanospheres were prepared by a hydrothermal method. The prepared samples were characterized by XRD, Pl, UV–Vis, BET, SEM, and TEM. The results reveal that Sn4+ replaces a small part of the Ti4+ from the TiO2 lattice. Doping of Sn increases the surface area of the TiO2 nanospheres.
Doping of Sn leads to a decrease in the band gap of the TiO2 nanospheres and increases the lifetime of the electron–hole recombination. Doping of Sn into the TiO2 nanospheres enhances the photocatalytic activity of the TiO2 nanospheres for the reduction of nitrobenzene to aniline under visible light. The optimal Sn loading was found to be 4 wt%. The photocatalytic activity of the 4 wt% Sn/TiO2 nanospheres is approximately 80 times greater than the photocatalytic activity of the TiO2 nanospheres.
Biography:
Elham Aazam has completed her Ph.D from Sussex University, UK and is a professor at King Abdulaziz University at the Science College and chemistry department. She is the head of the Chemistry department at the female campus; she has published 37 papers in reputed journals.
Dept. of Biochemistry, Collage of Science, King Saud University, Saudi Arabia
Background: Gold nanoparticles (GNPs) have emerged as important careers for drug delivery. However, immunological response of GNPs is complex and poorly understood.
Objective: To investigate the effects of small and medium sized gold nanoparticles on the inflammatory mediators in rat liver and kidney.
Methods: We studied the effects of small (10 nm) and medium (50 nm) sized GNPs on expression of proinflammatory cytokines, interlukin-1 beta (IL-1b), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in the liver and kidneys of rats.
Results: We observed that the expression of these cytokines in the liver was significantly higher than kidneys of rats exposed to GNPs. Both 10 and 50 nm GNPs significantly increased the cytokines gene expression in liver on day 1 which was reduced on day 5. In the kidney, only the medium sized GNPs significantly increased the expression of IL-6 and TNF-α on day 1, which was subsided on day 5.
Conclusion: These results show that GNPs exposure only transiently increases the expressions of proinflammatory cytokines that gradually subside with time. The current data on the biocompatibility of GNPs are limited and their interpretation is controversial.
Biography:
I have completed the Ph.D. in December 18, 1993 from the University of Akron, Ohio, USA and has joined King Saud University, Dept of Biochemistry, College of Science, Riyadh, Saudi Arabia since 1994. In 2002-2006 I became the Chairman of the Department of Biochemistry and in 2010-2012 I became the Vice-Dean of Graduate Studies and Scientific Research. I have published more than 115 papers in reputed journals and more three book-chapeters.
Currently I have been serving as an Editor-in-Chief of Saudi Journal of Biological Sciences, Associate Editor of the Jordan Journal of Biological Sciences and as editorial board member of repute.
I am currently working in the area of carnitine metabolism and its implication in human diseases. I am also studying the role of the carnitine pathway of energy metabolism in the Arabian camel (Camelus dromedarius), in order to explore the relationship between carnitine and the camelʼs superior ability to subsist in the harsh desert climate compared to other animals.
Another research area of my interest is to study the biochemical and molecular of nanomaterials, using both in-vivo and in-vitro models. More recently, my research interest extends in the area of diabetic retinopathy.
Ongoing Research Projects include: Neurodegeneration and neuroprotection studies in diabetic retinopathy, Hyperglycemia-induced oxidative stress in diabetic retina, glutamate excitotoxicity: a potential role in neurovascular damage in diabetic retinopathy.
Chungnam National University, Republic of Korea
Chitosan-silver nanocomposite (CAgNCs) was green synthesized without the adding any external chemical-reducing agents using low molecular weight chitosan (LMW-C) and silver nitrate. The synthesized nanocomposite was characterized by UV–visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM) with selected area electron diffraction (SAED), Inductively coupled plasma–atomic emission spectrometer (ICP–AES), particle size distribution and zeta potential analyzer. The average size of LMW-C and CAgNCs were 1776 ± 23 nm and 240.1 ± 23.6 nm, respectively. The zeta potential of CAgNCs observed as + 41.1 mV. It was indicating positively charged polymeric layer on AgNPs surface. The AgNPs are deposited on chitosan matrix and the average AgNPs particle size lies between 5 nm- 50 nm. The Ag content of the CAgNCs was 0.696± 0.054% (w/w). The CAgNCs also proved to be an excellent antifungal agent against candida albicans. The minimum inhibitory concentration (MIC) values of CAgNCs and LMW-C for C. albicans were recorded as 50 and 100 µg/mL, whereas the minimum fungicidal concentration (MFC) values of CAgNCs and LMW-C for C. albicans were recorded as 150 and 400 µg/mL respectively. Propidiumiodide (PI) uptake results suggested that CAgNCs has affected to permeability of cell membrane of C. albicans Also, CAgNCs induced the higher level of reactive oxygen species (ROS) when compare to the LMW-C in concentration dependent manner. This report illustrates the eco-friendly approach for the reduction of silver using chitosan as a reducing agent, and its potential antifungal agent against C. albicans.
Biography:
A Science Graduate holding a B.Sc special degree in Chemistry (University of Ruhuna, Sri Lanka) and M.Sc in Industrial Chemistry (University of Peradeniya, Sri Lanka). Now, I am working as graduate student following Master- PhD joint program at the College of Veterinary Medicine, Chunganm National University, and Republic of Korea. I have more than 5 yeses experience in nanotechnology and the author of two book (Sinhala language) and 8 scientific publication. Currently, I am working to develop biodegradable chitosan nano particle and chitosan metal (Silver and Gold) nanocomposite against pathogenic microbial.
College of health Sciences, School of Pharmacy, Department of Pharmacology and Clinical Pharmacy, Addis Ababa University, Ethiopia
Human immunodeficiency virus continued to be the greatest challenge and killer disease of the 21st century despite the advent of potent highly active antiretroviral therapy which are limited by their severe adverse effects, significant drug interactions, frequent dosing, limited bioavailability, and less access to viral reservoir sites like macrophages. Nano-medicines are becoming new hopes in avoiding these shortcomings of conventional antiretroviral drugs. The emphasis of this review is mainly the application of polymers based nanomedicines in pharmacotherapy of HIV/AIDS. Most of the studies to date on this area are in vitro and human clinical trials are totally missed. However, many interesting points are uncovered through this review like the possibility of achieving high intracellular concentration of drugs, very good antiretroviral activity, improved bioavailability, reduced toxicity and release of the drugs from nanocarriers for long time reducing the need for frequent dosing. Indeed, a lot of assignments left behind for researchers to overcome the challenges hindering the wider application of nanomedicines in treatment of HIV/AIDS.
Keywords: HIV/AIDS, Antiretrovirals, Nano-polymers, Nanomedicines
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