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2016 Seminars

In this Section

Fall 2016 Seminars

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Friday, December 2, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Dr. Sitaraman Krishnan

Chemical & Biomolecular Engineering Department

Clarkson University

will speak on

“Experimental and Computational Studies of Charge Transport in Microstructured Ionic Liquid and Polymer Electrolytes"

Abstract:

Thermally and electrochemically stable organic electrolytes are the key to flexible and durable energy storage devices, but are held back from commercialization by their low ionic conductivities. Better design of such electrolytes is possible by understanding ion conduction mechanisms in viscous multicomponent fluids. Microstructure and ion mobility are two important factors that determine electrical conductivity in electrolytes. The ionic conductivity of amorphous melts of several imidazolium salts were analyzed in the framework of composition dependent glass transition temperature and viscosity shift factor. The effect of local environment on ion dynamics was investigated using molecular dynamics simulations and NMR spectroscopy. Imidazolium ionic liquid electrolytes with phase segregating poly(ethylene glycol) and perfluoroalkyl groups were synthesized and found to exhibit over two orders of magnitude higher ionic conductivity than the prediction of Nernst-Einstein equation. Conjugated polymer membranes with electron- and ion-conducting pathways were prepared using ionic liquid as a component. These materials show significant promise as constituents of next generation lithium ion batteries and supercapacitors. 

Sita Krishnan

Professor Costel Darie (left) with Dr. Sitaraman Krishnan

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Friday, November 11, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Ali Othman

PhD Student

Clarkson University

will speak on

“Multifunctional Properties of Ceria Nanoparticles for Bio-Applications"

Abstract:

Cerium oxide nanoparticles have attracted considerable interest in the field of biomedical therapeutics, bio-diagnosis and biosensing due to their unique structure, interesting and unusual redox and catalytic properties, high surface area, good mechanical stability and biocompatibility.  Traditionally, cerium oxide nanoparticles have been used as polishing abrasives in the chemical mechanical planarization process in the manufacturing of printed circuits by the semiconductor industry and as a fuel additive in diesel particulate filters by the automotive industry. More recently, they have received considerable attention as therapeutic antioxidants to modulate oxidative stress in biological systems and as redox active probes to design bioanalytical assays. This presentation will discuss properties and applications of nanometer size cerium oxide nanoparticles and describe their implementation in the biomedical and bioanalytical fields. The surface reactivity, optical and catalytic properties of these particles, originating from their dual oxidation state and the highly mobile lattice oxygen present at their surface will be discussed with examples of applications. Recent results to tailor surface properties and their interface with biological systems will be presented. Finally, the impact of these particles in the environment and biological systems will be discussed. 

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Friday, November 11, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Ishah Hadi Alshehri

Clarkson University

will speak on

“Synthesis of Gradient Copolymers via Emulsion Reversible Addition Fragmentation Chain Transfer (RAFT) Polymerization"

Abstract:

In recent years, reversible addition fragmentation chain transfer polymerization (RAFT) polymerization has successfully demonstrated its ability to provide novel will-defined macromolecular architectures in homogenous and heterogeneous systems with a wide range of functional monomers. The work here focuses on the use of RAFT polymerizations to synthesize gradient copolymers with predetermined molecular weights and narrow molecular weight distributions. Gradient copolymers constitute an important class of polymeric materials within which the monomer composition varies smoothly along the length of the polymer chain. In particular, previous work demonstrated that gradient copolymers exhibit a broad glass transition temperature (Tg) range. Interestingly, the broad Tg of these polymers makes them extremely attractive for a wide variety of shape memory polymer (SMP) applications. Here we examine the use of RAFT emulsion polymerization to produce gradient copolymers with a broad Tg, and study the influence of monomer compositions on the transition breadth. Structure-property relationships were determined using gel permeation chromatography (GPC), 1H NMR spectroscopy, and differential scanning calorimetry (DSC).

Fig. 1

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Friday, October 28, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Anahita Karimi

PhD Candidate

Clarkson University

will speak on

“Electroanalytical investigation of Environmental Redox Processes at Metal Oxide Nanoparticles"

Abstract:

The electrochemical study of particle impacts on microelectrodes is a rapidly developing field which provides extensive capabilities for the characterization of nanoparticles. In this presentation, we describe the development of an electroanalytical collision technique to characterize the fundamental surface properties, functionalization and redox reactivity of metal and metal oxide nanoparticles by nano-impact electrochemistry.  We will demonstrate the potential of this method: (1) as a screening tool of particle reactivity, (2) study of the adsorption/desorption of environmental process and (3) extract mechanistic information that would be predictive of the chemical reactivity of nanoparticles for various applications. We will discuss the potential of this approach to complement or replace costly characterization techniques and enable routine study of nanoparticles and their reactivity.

Karimi Seminar

PhD Candidate Anahita Karimi

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Friday, October 28, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Elham Honarvar

Clarkson University

will speak on

“Electrochemically-controlled Biomolecules Release under Physiological Conditions from a Monolayer-modified Electrode"

Abstract:

An indium tin oxide (ITO) electrode prepared on a flexible polymeric support was modified with an amino-silane and then functionalized with trigonelline and 4-carboxyphenylboronic acid covalently bound to the amino groups. The trigonelline species containing quarterized ammonium group produced positive charge on the electrode surface regardless of the pH value, while the phenylboronic acid species were neutral below pH 8 and negatively charged above pH 9 (note that their pKa = 8.4). The total charge on the monolayer-modified electrode was positive at the neutral pH and negative at pH > 9 (note that 4-carboxyphenylboronic acid was attached to the electrode surface in excess to trigonelline, thus allowing the negative charge to dominate on the electrode surface at basic pH). Single-stranded DNA molecules or insulin were loaded on the modified electrode at pH 7.0 due to their electrostatic attraction to the positively charged surface. By applying electrolysis at -1.0 V (vs. Ag/AgCl reference) electrochemical oxygen reduction resulted in the consumption of hydrogen ions and local pH increase in the vicinity of the electrode surface. The process resulted in the transition to the total negative charge due to the negative charges formed on the phenylboronic acid species. This resulted in the electrostatic repulsion and release of the loaded DNA or insulin. The developed approach allowed the electrochemically-triggered DNA and insulin release not only in the aqueous solutions, but also in human serum solution, thus giving promise for future biomedical applications.

Honarvar Seminar

Professor Evgeny Katz (right) with Elham Honarvar

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Friday, October 21, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Professor Jörn Wochnowski

Fachhochschule Lubeck, Germany

will speak on

“Selected Coating Technologies for Modification of Micro- and Nanostructured Materials"

Abstract:

In this talk, different selected coating technologies like Chemical vapor deposition (CVD) are introduced. These different coating methods are discussed intensively for the modification of micro- and nanostructured materials like Metal Organic Frameworks (MOFs) or Mobil Composition of Matter (MCM).

The ultimate application of these micro- and nanostructured materials modified by e.g. metals is their use as catalytic material in chemistry.

For this purpose organometallic, elementorganic and coordination compounds are decomposed chemically in macro-, meso-, micro- and nanosystems. Thus, a specific surface structure for the respective application can be realized. To achieve this objective the right choice of substrate material is relevant.

Professor Mario Wreidt (left) with Professor Jörn Wochnowski

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Friday, October 14, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Dr. Louise Dawe

Department of Chemistry and Biochemistry

Wilfrid Laurier University, Waterloo, ON, Canada 

will speak on

“A Scaffolded Approach to the Integration of Crystallography in Undergraduate Curriculum and Research"

Abstract:

Project scaffolding, as a tool to achieve learning outcomes, supports the immediate construction of knowledge by the learner, provides the basis for the future independent learning of the individual, and enables learners to reach otherwise unattainable goals. During 2014, the International Year of Crystallography provided an opportunity for the redesign of a required third year Honors course on Chemical Literature and Scientific Communication at Wilfrid Laurier University. While course outcomes were based on recommendations for information literacy, a scaffolded approach to student projects, thematically based on the broad exploration of crystallography, was employed to achieve these stated objectives. The course culminated in the Faculty of Science poster conference, where third year students taught first year students about science that takes place “outside of textbooks.” The enthusiasm and engagement of students, both as learners and instructors, was energizing.

In addition to providing an overview of project scaffolding practices, this seminar will also provide examples for the integration of crystallography into first year general chemistry, second year inorganic, and senior undergraduate capstone courses. Further to highlighting curricular opportunities for students to learn about crystallography, recent research progress in fundamental areas of crystallography (polymorphism and structure modulation), carried out by undergraduates in my research program, will be discussed.

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Friday, October 7, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Dr. Marcel Musteata

Albany College of Pharmacy and Health Services 

will speak on

“IN VIVO ANALYSIS AND PRECISION MEDICINE"

Abstract:

The field of bioanalysis has seen an accelerated development in the last years, with an emphasis on progressively miniaturized techniques. The methods employed in bioanalysis must be accurate, precise, fast, ideally error free, efficient, and should use reagents that are not harmful to the analyst or the environment. Many of these requirements are met nowadays; however, one of the most problematic parts of bioanalysis remains the sample preparation step.

This presentation will discuss recent developments in the area of in-vivo sampling and sample preparation for analysis of biological systems. The trend towards microanalytical techniques is justified by the small amount of sample that is available from some biological systems and also by the need to minimize the interference with the system that is studied or analyzed. Different approaches for direct in-vivo sampling and sample preparation will be briefly described, including microsampling and microextraction. Recent applications developed in our laboratories include quantification of active compounds and fingerprinting of medicinal plants, in vivo brain analysis, pharmacokinetic studies in single rodent, and personalized therapeutics.

These recently developed monitoring systems have an increased potential of finding application in clinical practice.

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Friday, September 30, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Dr. David Pahovnik

Department of Biochemistry and Molecular Pharmacology

National Institute of Chemistry, Department of Polymer Chemistry and Technology, Hajdrihova 19, 1000 Ljubljana, Slovenia

will speak on

“Ring-opening polymerizations of heterocyclic monomers"

Abstract:

Polyethers, polyesters and polypeptides can be synthesized by ring-opening polymerization of corresponding cyclic monomers, i.e. epoxides, lactones and N-carboxyanhydrides, respectively. Ring-opening polymerization usually results in polymers with controlled molar mass characteristics and chain-end fidelity which enable the preparation of block-copolymers and polymers with complex macromolecular architectures. Due to different reactivity of individual monomers various initiator/catalytic systems are usually required for a good control over the polymerization. In this presentation different approaches to one-pot sequential block-copolymerization of monomers with significantly different reactivity and the use of unconventional initiators will be discussed, supported by detailed characterization of macromolecular structures of the resulting polymers. Additionally, some examples of various post-polymerization modifications to prepare polymers with specific properties for biomedical applications will be presented.

Figure 1

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Monday, September 26, 2016

10:00 a.m.
Science Center 244

Gonca Bülbül

PhD Defense

Clarkson University

will speak on

“Synthesis and characterization of Ag/SU-8 nanocomposites for piezoresistive applications"

Abstract:

The adoption of nanoparticle based analytical technologies has gained increasing acceptance in various fields of chemical analysis in the environmental, clinical, food and biomedical sectors. The combination of biorecognition elements with nanomaterials allows the design of hybrid sensing systems with high target specificity and selectivity. This presentation will describe properties and assembly of nanoceria particles in conjunction with ssDNA aptamers as a novel platform for biomolecular recognition.  The method involves reversible target tunable assembly of ssDNA to the surface of nanoceria which changes its functional properties upon binding of the target analyte. This approach is generally applicable for detection of a wide spectrum of analytes, since any aptamer–target binding event can in principle be translated to conformational transition and be detected based on this strategy. Detection of Ochratoxin A, a low molecular weight mycotoxin will be discussed as an example of application. The results open up new ways of designing optical and electrochemical sensing methods using aptamer recognition and nanoparticle probes.  This novel approach can be used as a universal platform for the development of biorecognition assays for diagnostics, food and environmental monitoring applications.

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Friday, September 16, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Dr. Thomas Neubert

Department of Biochemistry and Molecular Pharmacology

New York University

School of Medicine 

will speak on

“Mass Spectrometry of Proteins and Metabolites to Study Signaling and Tumorigenesis in Neurons"

Abstract:

Stable Isotope Labeling by Amino Acids in Cell Culture (SILAC) is a useful strategy for the study of cell signaling, and primary neurons are an important model for the study of signaling in the nervous system. I will discuss the utility of SILAC in primary neurons to study nerve growth factor signaling despite incomplete labeling of proteins in these non-dividing cells. I will also discuss combining SILAC with Bioorthogonal Noncanonical Amino Acid Tagging (BONCAT) to study brain-derived neurotrophic factor (BDNF)-stimulated synthesis of new proteins. Finally, I will describe our analysis of metabolic changes in IDH1 mutant neuronal stem cells in a model of gliomagenesis.

Thomas Neubert

Professor Costel Darie (right) with Dr. Thomas Neubert

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Friday, September 16, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Lina Bian

Clarkson University

will speak on

“Synthesis and characterization of Ag/SU-8 nanocomposites for piezoresistive applications"

Abstract:

Photocurable nanocomposites have excellent processability and patternability that could enable site-specific deposition of materials for device integration using microfabrication techniques. In this study, the negative photoresist SU-8 is selected as a matrix due to its excellent biocompatibility, chemical resistance, and mechanical integrity. As the content of embedded Ag nanoclusters increases, they undergo a transition from isolated islands to a semi-continuous network that evolves to a fully interconnected network.  As a result, the electrical behavior of nanocomposites evolves from “dielectric” to “metallic” with a sharp transition region that is characteristic of percolation.  To understand this change of electrical properties as a function of nanocomposite composition, several characterization techniques have been employed. DC electrical properties of the Ag /SU-8 nanocomposites were investigated using both 2 probe and 4 probe resistivity measurements.  Frequency dependent AC responses were measured using impedance spectroscopy and equivalent circuit models were derived using MEISP software.  I-V behavior of the nanocomposite was examined to gain further insight into the nanocomposite conduction mechanism, suggesting that the conduction may be related to a thermally activated tunneling mechanism during percolation.  In addition, synthesis and characterization of high-aspect-ratio Ag nanowires have been attempted, aiming for reduced loadings of conductive fillers and enhanced performance.

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Friday, September 9, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Professor Brett P. Fors

Department of Chemistry and Chemical Biology

Cornell University

will speak on

“Shaping the Future of Polymer Molecular Weight Distributions"

Abstract:

A polymer’s molecular weight distribution (MWD) has a profound impact on its properties, from material strength and viscosity to changes in the phase behavior of block copolymers. Dispersity is the most common measure of MWD and is described as the ratio of weight-average (Mw) to number-average (Mn) molecular weights. Importantly, dispersity only provides information on the relative breadth of molecular weights in a sample and is not a comprehensive description of the molar quantities of each chain size. The exact shape of a MWD has been proposed to have a strong influence on polymer properties; however, this hypothesis remains relatively unexplored. This presentation will detail the development of a modular synthetic strategy that provides deterministic control over the Mnbreadth, and composition of polymer MWDs and will examine the influence of MWD shape on polymer properties.

Fig. 1

Professor Fors

Professor Devon Shipp (left) with Professor Brett Fors

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Friday, September 2, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 214

Dr. Linny Ju

Bruker Daltonics

Billerica, Massachusetts

will speak on

“Introduction of MALDI-TOF MS and its applications"

Abstract:

MALDI-TOF MS represents a commonplace analytical technique that combines matrix assisted laser desorption/ionization with time of flight mass spectrometry to obtain molecular weight information. In a typical MALDI MS analysis, the analyte is co-crystallized with a matrix compound, after which the analyte-matrix mixture is desorbed and ionized upon laser radiation. MALDI-TOF MS can operate in both linear and reflector mode, and the latter one offers improved resolution. Typical applications of MALDI-TOF MS includes protein identification by peptide mass fingerprinting, data dependent MS/MS acquisition for proteomics applications, MALDI top down sequencing of intact proteins, characterization of polymers by MALDI MS  and MALDI tissue imaging. In this presentation, general MALDI MS background and instrumentation will be introduced, and the recently acquired MALDI MS data for Clarkson University will be presented along with several other MALDI MS applications to demonstrate the instrument capability.

Professor Costel Darie (right) with Dr. Kasia Janota of Bruker Daltonics

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Summer 2016 Seminars

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Tuesday, July 26, 2016

2:00 p.m.
Bertrand H. Snell Hall Room 214

Brian E. Fratto

PhD Defense

Clarkson University

will speak on

“Utilization of a Fluidic Infrastructure for the Realization of Novel Boolean Logic Operations: A Modular Approach to Enzymatic Biomolecular Information Processing"

Abstract:

This thesis documents the progress that has been made in the field of unconventional computing based on molecular and biomolecular systems.  Previously, the progress made in the field, had fostered the ability to recreate many systems that are able to mimic their electronic counterparts by performing Boolean logic operations. Although the novelty and ingenuity needed to develop homogeneous systems cannot be understated, the ability to organize enzymatic systems with the use of a network of flow cells in which each modified with one enzyme that biocatalyzed one chemical reaction has permitted the novel mimicking of switchable logic gates as well as specific reversible logic gates that were previously difficult to recreate.

The gates that have been created with the use of this modular enzymatic approach include the reversible Double Feynman Gate, Toffoli Gate, Peres Gate, Switch Gate and Fredkin Gate, as well as the non-reversible, switchable OR, NXOR, and NAND systems, the Half-Adder, and the Half-Subtractor. Furthermore, the utilization of modular fluidic devices has not only allowed for the realization of these systems, but has also made it possible to bypass many difficulties that hinder traditional biocomputing systems. In addition to the advantages from the separation of channels and clocking, the use of modular fluidic devices also allows data signals to be routed between different Output channels.

In the addition to the straightforward mimicking of the Boolean logic operations that utilize these modular fluidic systems, there is also the ability to integrate these systems into complex biomolecular networks, as well as sense-and-act/logically controlled release systems.  Such abilities will give future unconventional biocomputing and bioanalytical systems added benefits leading to a degree of autonomy that is needed for truly theranostic systems.

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Spring 2016 Seminars

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Tuesday, May 24, 2016

9:00 a.m.
Bertrand H. Snell Hall Room 212

Marion Bruchet

PhD Defense

Department of Chemical and Biomolecular Science
Clarkson University

will speak on

Photoresponsive Alginate Hydrogels and their Derivatization with Small Molecules

Abstract:

The creation and commercialization of 3D printing in conjunction with the optimization of photolithography techniques have opened new doors to create scaffolds for tissue engineering. The main drawback of most 3D printed scaffold is the cytotoxicity of either the polymers used or the products formed by their degradation.

This project aims at answering this by reverse engineering these issues. A biocompatible polymer, alginate, was used with a redox crosslinker to make it photoresponsive. This polysaccharide can form a hydrogel by crosslinking hard metal cations. Using iron(III) as a crosslinker, the gels obtained proved to be responsive to light in the presence of a photoreducing agent. The photo-responsivity of ferric alginate not only allowed for its in-depth patterning and a surface etching but also provided a template for the fabrication of homogeneous alginate hydrogels crosslinked with other hard cations. The patterned gels were also turned non-responsive to their environment by further chemical crosslinking of the polymer with a diamine compound, Cystamine. A new technique was developed to create thin-layer assembly of photodegradable iron(III) alginate layers. This technique is a new step toward the creation of scaffolds suitable for tissue engineering. The presence of carboxylate groups on alginate made possible its derivatization with small molecules such as amino acids, fluorescent dyes and proteins, which could be of use later on for drug delivery systems. The use of iron(III) alginate nanoparticles as ‘smart’ carriers was investigated, using Förster Resonance Energy Transfer between two fluorescent dyes, coumarin and fluorescein.

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Friday, April 8, 2016

12:30 p.m.
Science Center Room 244

Sapan J. Patel

PhD Defense

Department of Chemical and Biomolecular Science
Clarkson University

will speak on

“Quorum Sensing in Acute Lymphoblastic Leukemia

Abstract:

The creation and commercialization of 3D printing in conjunction with the optimization of photolithography techniques have opened new doors to create scaffolds for tissue engineering. The main drawback of most 3D printed scaffold is the cytotoxicity of either the polymers used or the products formed by their degradation.

Quorum sensing (QS) is a generic term describing cell-cell communication and collective decision making by bacteria and social insects to regulate expression of specific genes controlling cell density and other properties in response to changes in nutrient supply or environment. In this work, we used a p190BCR-ABL driven pre-B acute lymphoblastic leukemia (ALL3) cell line derived from an adult patient with ALL to test the QS hypothesis in leukemia. ALL3 cells don’t grow at low density (LD) in liquid media, in-vivo in mice but grow progressively faster at increasingly high cell densities (HD) in contrast to other established leukemic cell lines that grow excellently at very LD. The ALL3 cells at LD are poised to grow but shortly die without additional stimulation. Supernates of ALL3 cells (HDSN), some of the established leukemic cell lines and some other primary cells grown at HD stimulate the growth of LD ALL3 cells without which they won’t survive. Microarray analysis of the LD ALL3 cells after stimulation with ALL3 HDSN identified several candidate genes involved in lipid, cholesterol, fatty acid metabolism, and B cell activation. Amongst the list of genes, FAM129C (BCNP1) was found to be highly upregulated that might have specific role in B cell leukemia and other cancer. Diffusible soluble proteins and exosomes that are considered as a part of secretomes both stimulate the growth of non-growing LD ALL3 cells. Our findings suggest that the Ph+ ALL population achieves dominance by functioning as a collective aberrant ecosystem subject to defective quorum-sensing regulatory mechanisms. Ultimately we define the aberrant circuitries suitable for developing specific therapies against vulnerable targets in leukemias and maybe other cancers.

Sapan Patel

Dr. Costel Darie (left) with Ph.D. Candidate Sapan Patel

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Friday, April  8, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Dr. Zijie Yan

Department of Chemical and Biomolecular Engineering
Clarkson University

will speak on

Optical Trapping and Manipulation of Colloidal Nanocrystals

Abstract:

Size- and shape-controlled synthesis of colloidal nanocrystals has been feasible for many materials using wet chemistry methods, yet spatial and temporal control of these nanomaterials remains a challenge due to intense Brownian motion of nanoparticles in solution. The ability to manipulate small objects is essential in studying many microscopic phenomena, not only in colloid science, but also in molecular biology and nanomanufacturing. In this seminar, I will introduce the techniques and mechanisms to control nanomaterials with light, including detailed discussions of the interactions of light with plasmonic nanostructures. In particular, I will describe holographic optical tweezers that use structured laser beams to tailor the optical trapping of specific silver nanostructures, and the light-induced self-assembly of silver nanoparticles due to significant electrodynamic interactions (i.e., “optical binding”) in simple optical fields. The possibility to control and manipulate microscopic objects provides new opportunities to study the light-matter interaction at the nanoscale, and enables improved technologies for studies in chemistry & biomolecular science.

Figure 1

Dr. Zijie Yan

Professor He Dong (right) with Dr. Zijie Yan

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Friday, April  15, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Professor Richard A. Gross

Rensselaer Polytechnic Institute (RPI), Constellation Chair: Biocatalysis and Metabolic Engineering,  Center for Biotechnology and Interdisciplinary Studies; Professor, Department of Chemistry and Biology, Professor of Biomedical Engineering, 4005B BioTechnology Bldg., 110 8th Street, Troy, N.Y. 12180

http://www.poly.edu/grossbiocat/; grossr@rpi.edu

will speak on

The expanding role of enzyme catalyzed synthesis of polymers, surfactants and peptides

Abstract:

Cell-free lipase biocatalysis, due to the mild temperatures at which they catalyzed reactions as well as their extraordinary selectivity, provide numerous benefits when synthesizing polyesters, polycarbonates and polyamides. As an example, the use of lipase-catalyzed condensation polymerizations using multifunctional building blocks such as glycerol and sorbitol provide a versatile family of functional polymers.  Crosslinking is avoided during lipase-catalyzed polymerizations due to the steric hinderance at active sites. Furthermore, mild polymerizations allow the incorporation along chains of chemically sensitive moieties. Biocatalysis using whole cells provides important new routes to biobased monomers and biosurfactants from renewable feedstocks. As an example, the biosynthesis and properties of modified sophorolipids will be discussed.  The polymerization of lactonic sophorolipids by ring-opening metathesis polymerization (ROMP) leads to highly functional bioresorbable polymers.  Poly(sophorolipids) are cytocompatible with human mesenchymal stem cells (h-MSCs) and can induce osteogenic cell lineage progression.  Molecular editing of natural sophorolipids has been used to develop a library of low molar mass sophorolipid analogs. Examples of how this approach allows the tuning of sophorolipid interfacial and biological properties will be discussed.  Finally, our group is developing mild and efficient protease-catalyzed routes for peptide synthesis. Examples will be given of protease-catalyzed routes to peptides with various properties such as self-assembly, antimicrobial and metal chelation.  A future perspective will be given on the potential of protease-catalysis for peptide synthesis.

Professor Richard A. Gross

Professor He Dong (right) with Professor Richard A. Gross

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Friday, April  8, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Professor Vincent Conticello

Department of Chemistry
Emory University

will speak on

Peptide and Protein Nanomaterials: The Design Challenge

Abstract:

Structurally defined materials on the nanometer length-scale have been historically the most challenging to rationally construct and the most difficult to structurally analyze. Sequencespecific biomolecules, i.e., proteins and nucleic acids, have advantages as design elements for construction of these types of nano-scale materials in that correlations can be drawn between sequence and higher order structure, potentially affording ordered assemblies in which functional properties can be controlled through the progression of structural hierarchy encoded at the molecular level. However, the predictable design of self-assembled structures requires precise structural control of the interfaces between peptide subunits (protomers). In contrast to the robustness of protein tertiary structure, quaternary structure has been postulated to be labile with respect to mutagenesis of residues located at the protein-protein interface. We have employed simple self-assembling peptide systems to interrogate the concept of designability of interfaces within the structural context of nanotubes and nanosheets (see below). These peptide systems provide a framework for understanding how minor sequence changes in evolution can translate into very large changes in supramolecular structure, which provides significant evidence that the designability of protein interfaces is a critical consideration for control of supramolecular structure in self-assembling systems.

Figure 1 and Figure 2

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Friday, April 1, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 213

Jesse Pokrzywinski

Ph.D. Student
Clarkson University

will speak on

“Waste Milk Derived Carbons with Surface Area Surpassing Graphene Offer Extraordinary Supercapacitance”

Abstract:

Here we demonstrate a facile template-free synthesis route to create macroscopically monolithic carbons that are both highly heteroatom rich (>10% N,O) and highly microporous (SA up to 3074 m2 g-1, 90vol% useful micropores and small mesopores). While such materials, which are derived from waste milk, are expected to be useful in a variety of applications, they are extremely promising for electrochemical capacitors based on aqueous electrolytes.  The Milk Activated Carbons (MAC) demonstrate a specific capacitance > 700 F g-1 at 0.25A g-1and > 350 F g-1 at 10 A g-1 in their optimized state. These are among the highest values reported in literature for carbon-based electrodes, including for systems such as templated carbons and doped graphene. We show that MACs serve as ideal electrode materials for supercaps; symmetrical cells employing neutral electrolytes and MACs demonstrate > 2.5X higher specific energy as compared to one employing a state-of-the-art commercial activated carbon. Specific energies (active mass normalized) of >60 Wh kg-1 at 230 W kg-1 and >40 Wh kg-1 at 1900 W kg-1 are achieved.  The symmetrical cell performance is among the best in literature for symmetrical aqueous systems, and actually rivals cells operating with a much wider voltage window in organic electrolytes.

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Friday, March 25, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Professor Omar K. Farha

Department of Chemistry
International Institute of Nanotechnology Northwestern University

will speak on

Catalytic Metal-Organic Framework Materials

Abstract:

Metal–organic frameworks (MOFs) are an emerging class of solid-state materials built up from metal-based nodes and organic linkers. They exhibit permanent porosity and unprecedented surface areas which can be readily tuned through coordination chemistry at the inorganic node and/or organic chemistry at the linkers. The high porosities, tunability, and stability are highly attractive in the context of catalysis. As exemplified by many catalytic enzyme assemblies in nature, site-isolation is a powerful strategy for performing catalytic reactions. MOFs provide an exciting platform for deploying catalysts in a site-isolated fashion and the cavities surrounding them can be engineered to conceptually mimic enzymes. This talk will address new advances in the synthesis and catalytic activity of MOF materials developed at Northwestern University.

Professor Mario Wreidt (right) with Professor Omar K. Farha

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Friday, March 11, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Devika Channaveerappa, M.S.

Ph.D. Student
Clarkson University

will speak on

“Functional Investigation of Human Jumping Translocation Breakpoint (hJTB) Protein by Mass Spectrometry-based Proteomics”

Abstract:

Human JTB (hJTB) is a gene located on the human chromosome 1 at q21 which is involved in the unbalanced translocation in various types of cancer. JTB protein is ubiquitously present in normal cells and is found to be overexpressed in different types of cancer including prostate and breast cancer. Hence this protein could be a tumor biomarker for different types of malignancies and a potential target for their treatment. However, the biological function and the pathway through which this protein causes increased cell growth and proliferation is not entirely clear. Investigation and comparison of the proteomes of cells with upregulated and downregulated JTB can be a good approach to understand the function of the protein and also its contribution to tumorigenesis. In this study, MCF7 breast cancer cell lines were transfected with the sense and antisense orientation of the JTB cDNA in HA, His and FLAG tagged CMV expression vector. The expression of JTB was confirmed by western blotting. Proteins extracted from transiently transfected cells were separated using SDS-PAGE and the in-gel digested peptides were analyzed by a Nano Acquity UPLC coupled with Xevo G2 Mass Spectrometer. Data analysis was done using Mascot server and Scaffold 4.1 software. In addition, two other JTB isoforms are currently investigated and their possible cellular function(s) will be compared with the functions of the wild type JTB. These studies could help us elucidate the mechanism through which JTB induces cell proliferation and test the JTB protein as a potential drug target for malignancies with overexpression of the protein.

Professor Costel Darie (right) with Ph. D. Student Devika Channaveerappa

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Friday, March 4, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Professor Ryan C. Hayward

Polymer Science and Enginering
The University of Massachusetts Amherst

will speak on

Programming shape and structural color with polymer nanocomposites”

Abstract:

Our group seeks to fabricate and understand the behavior of reprogrammable materials, particularly those with functions mimicking the complex adaptive responses common in nature. Polymer nanocomposites, which can combine the chemical versatility and large strain responses possible with polymers, with the attractive optical, electronic, or magnetic characteristics of inorganic nanoparticles, offer unique opportunities in this regard.  We have recently studied two main classes of responsive nanocomposite materials. In the first case, we seek to harness spatially non-uniform stresses within thin polymer sheets and multilayers to drive out-of-plane buckling modes that can control the three-dimensional shapes of materials. Light-responsive elements within such constructs offer possibilities for dynamically reconfigurable materials that can be remotely controlled, with high resolution in both space and time. We have recently studied several examples of hydrogel-based sheets and multilayers where photoswitching is enabled through photothermal actuation of nanocomposite gels and liquid crystalline polymers. In the second case, we take advantage of interference of light reflected from within periodically structured dielectric media to define responsive photonic coloration. With multilayer polymer films alone, the modest contrast in refractive index means that many layers are required to achieve highly efficient reflection. Thus, the incorporation of high refractive-index inorganic nanoparticle species represents an attractive means to improve performance while simplifying fabrication.

Professor Devon Shipp (right) with Professor Ryan C. Hayward

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Friday, February 26, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212

Gonca Bülbül

Ph.D. Student
Clarkson University

will speak on

Portable Technologies for Point of Care Testing (POCT)”

Abstract:

The need for portable Point-of-Care Testing (POCT) devices that can provide rapid, low cost and continuous measurement of analytes in the biomedical, food and environmental monitoring fields is growing. This seminar will discuss development, fabrication, analytical characterization and deployment of POCT devices. The second part of the seminar will describe our recent efforts to develop a new portable technology using redox active nanoparticles as colorimetric agents and signal amplifiers to reduce the number of measurement steps and increase detection sensitivity and portability of bioassays. Several applications of this platform for monitoring enzymatic and bioaffinity reactions in a single step procedure will be discussed. The method takes advantage of the reactivity of cerium oxide nanoparticles with products of the enzyme catalyzed reaction, resulting in charge transfer complexes with very strong absorption characteristics. The developed assay is easy-to-use and does not require labeled reagents, secondary enzymes or soluble dyes. The proposed assay can eliminate multistep procedures and minimize problems associated with the poor stability of substrates and enzyme labels of conventional enzyme assays. The assay has been adapted to a paper platform and has demonstrated functionality for detection of enzyme activity in human serum. This sensing concept can find wide applications as a general approach for improving sensitivity and simplifying detection schemes of colorimetric bioassays, e.g. enzyme, gene, immuno and aptamer assays and related affinity sensing methods.

Bülbül Seminar

Professor Silvana Andreescu (right) with Ph.D. Student Gonca Bülbül 

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Friday, February 19, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Brian E. Fratto

Ph.D. Candidate

Clarkson University

will speak on

“Controlled Logic Gates – Realizing the Switch Gate and Fredkin Gate utilizing Enzyme-Biocatalyzed Reactions in Flow Cells”

Abstract:

Progress in the field of unconventional computing based on molecular and biomolecular systems, has fostered the ability to re-create many systems that are able to mimic their electronic counterparts by performing Boolean logic operations.  The ability to organize enzymatic systems by using a network of flow cells, each modified with one enzyme that biocatalyzed one chemical reaction has permitted the novel mimicking of switchable logic gates in addition to specific reversible logic gates. These gates include the Double Feynman Gate, Toffoli Gate, Peres Gate and switchable OR, NXOR, and NAND systems. Further utilization of the modular fluidic devices has not only allowed for the realization these systems, but has also made it possible to bypass many difficulties that hinder traditional biocomputing systems. In addition to the advantages of clocking and separation of channels, the use of modular fluidic devices also allows for the routing of Data signals between different output channels.  In the specific case of the Switch Gate and Fredkin Gate, the modular design of the enzyme-based systems, which have been realized in the flow device, has allowed for easy reconfiguration of the logic system. Thus, allowing the simple extension of the logic operation from the 2-input/3-output channels in the Switch Gate to the 3-input/3-output channels in the Fredkin gate.

Fratto Seminar

Professor Evgeny Katz (right) with Ph.D. Candidate Brian E. Fratto

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Friday, February 12, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Dr. Jason B. Benedict

Department of Chemistry

University at Buffalo, the State University of New York

will speak on

“Watching crystals work: Structural dynamics of metal-organic frameworks”

Abstract:

Photochromic technologies have the potential to transform traditionally passive materials into active materials which change their chemical or electronic properties in response to light stimulus. New photochromic materials are being synthesized and reported at an extremely rapid rate driven in large part by the numerous potential applications for these advanced materials including molecular switches, sensors, data storage, photomechanical devices and even biological switches. One of the newest emerging applications for photochromic technologies being developed in the Benedict research lab is the development of photo-responsive metal-organic frameworks (MOFs): highly porous crystalline frameworks capable of undergoing structural reorganization upon application of light. The Benedict group is also developing cutting edge in situ X-ray diffraction techniques to study the structural reorganization, both photo-induced and through guest exchange, under ‘real world’ conditions in order to develop a molecular level understanding of the processes that occur within these important materials.

Professor Mario Wreidt (right) with Dr. Jason B. Benedict

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Friday, February 5, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Dr. He Dong

Dept. of Chemistry & Biomolecular Science

Clarkson University

will speak on

“Supramolecular Assembly of Peptidic Biomaterials: From Molecular Design and Understanding to Therapeutics Development”

Abstract:

Peptide-based supramolecular assemblies represent an important class of soft nanomaterials with hierarchical structural control down to the molecular level. The well-defined molecular structure plays important roles in regulating supramolecular structure, property and various biological activities. In this seminar, I will discuss two self-assembling systems based on de novo designed peptides and their therapeutic applications. The first system is inspired by amyloid nanofibers. By manipulating the attractive and repulsive force through primary sequence variation, nanofibers were formed with desirable features of controlled assembly, nanostructured dimensions, atomically precise localization of chemical functionality ideal for anisotropic nanocarrier design. In a second example, I will discuss a new design of artificial proteins through self-assembly of a two-component chimeric peptide. The synthetic peptide self-assembled into discrete tetrahedron-like protein nanoparticles driven by a combination of symmetry controlled molecular packing and geometric constraint. These preliminary findings are expected to help establish a fundamental understanding of how molecular design impacts folding and assembly of multi-component peptides. It will also help develop more sophisticated peptide-based molecular toolkits for the construction of discrete protein-like nanoparticles with well-defined molecular pattern, increased complexity and diverse functionality.

He Dong Seminar

Dr. He Dong (left) with graduate students Linhai Jiang (center) and Dawei Xu (right). 

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Friday, January 29, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Professor Dan Goia

Dept. of Chemistry & Biomolecular Science

Clarkson University

will speak on

“Room temperature sinetrable silver nanoparticles for printable electronics”

Abstract:

Noble metals nanoparticles are widely used in electronics, catalysis, optics, medicine, biology, thin film solar cells, and transparent conductive coatings. The technological advances of all these applications depend on the ability to control the particles size, size distribution, morphology, internal structure, and surface properties. In this regard, there is a strong interest in developing simple, cost effective, and scalable preparation methods capable of synthesizing materials with characteristics that address the specific requirements of a wide range of practical applications.

Inkjet printable conductive structures based on silver nanoparticles are rapidly integrated not only in the traditional electronic components and devices but also in novel applications in displays, sensors, and solar cells. In the case of flexible or thermally sensitive substrates, lowering the sintering temperature of Ag particles is the main technology driver. For this reason, developing particles that could be consolidated into electrically conductive elements/structures at ambient temperature has been for some time now the ‘Holy Grail’ of the electronic industry. The presentation will give an overview of a new type of silver nanoparticles that can form electrically conductive layers at room temperature. The research strategy used in the development of the particles will be discussed in detail and their unique properties will be reviewed. The ability to generate at room temperature (and matter of minutes) highly conductive patterned layers on various substrates will be demonstrated to the audience. Finally, new and exciting applications in existing and emerging technology fields will be proposed.

Dan Goia Seminar 2016

Professor Dan Goia (left) with Dr. Ajeet Kumar

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Friday, January 22, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Professor Devon A. Shipp

Dept. of Chemistry & Biomolecular Science

Clarkson University

will speak on

“Polyanhydrides: Versatile Biomaterials for Drug Delivery, Shape Memory Polymers, Self-Healing Materials and Nanoparticles”

Abstract:

Polyanhydrides have found a niche in the degradable polymer field, largely because they often undergo surface erosion, but demanding synthesis conditions have held them back from widespread use. To address this problem, we have developed novel polyanhydrides that are based on thiol-ene ‘click’ polymerization, an easy to conduct step-growth mechanism of polymerization that can be applied to make materials that have relatively uniform network structure. Further, thiol-ene ‘click’ polymerization is robust, can be photo-, redox- or thermally-initiated and may use a wide variety of monomers. Thus, these have real potential in a variety of applications, including orthopedics and drug delivery.

Discussed in this presentation will the be the synthesis of elastomeric and semi-crystalline polyanhydrides that have controllable degradation rates, and how this approach to network polyanhydrides can provide significant flexibility in tailoring characteristics such as crosslink density, functionality and hydrophilicity. In particular, it will be shown that polyanhydrides can be used in applications such as drug delivery, can also behave as shape memory polymers, exhibit self-healing properties and can be produced as nanoparticles.

Professor Devon Shipp (center) with graduate students Olivia Durham (left) and Kelly Tillman (right)

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Friday, January 15, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Jennifer Ritz

Ph.D. Candidate

Clarkson University

will speak on

“Investigations into the Synthesis of Thiolate-Protected Metal Nanoparticles”

Abstract:

The two-phase Brust-Schiffrin synthesis was developed in 1994 to produce alkanethiolate-protected gold nanoparticles (1-10 nm) that are dispersible in organic media.  It has since been widely employed for a variety of different metals because the products are typically highly stable, relatively monodisperse, and can be dried, stored, and redispersed without significant change.  In these syntheses, metal halide anions are phase-transferred from water to toluene using the phase-transfer agent tetraoctylammonium bromide, generating an ion-pair complex in the organic phase. This phase is then isolated and thiol ligands are added. Finally, a two-phase reduction process is initiated with the addition of an aqueous solution of sodium borohydride.

Over the years, these nanoparticles have been studied extensively by several groups, but little attention has been paid to developing thorough mechanistic understanding of the relatively complex, three-step syntheses for various metals. As a result, synthetic control is currently lacking. In this seminar, several mechanistic studies into the Brust-Schiffrin synthesis of thiolate-protected Pd nanoparticles will be presented.

Additionally, a novel method for the single-phase synthesis of organosoluble thiolate-protected nanoparticles of several different metals (Au, Pd, Ag) is presented here.  Ion-pair complexes of tetraoctylammonium cation and different metal-halide anions are reacted in toluene with an organosoluble reductant in the presence of alkanethiol. This facile, single-step reaction utilizes stable, well-defined precursor species and yields monodisperse nanoparticles comparable to those produced using the more complicated, multistep, two-phase methods.

Professor Paul Goulet (right) with Ph.D. Candidate Jennifer Ritz

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Friday, January 8, 2016

3:30 p.m.
Bertrand H. Snell Hall Room 212
Professor David Mitlin

Chemical & Biomolecular Engineering and Mechanical Engineering

Clarkson University

will speak on

“Coupling in-situ TEM and ex-situ analysis to understand heterogeneous sodiation of antimony”

Abstract:

We employed an in-situ electrochemical cell in the transmission electron microscope (TEM) together with ex-situ time-of-flight, secondary-ion mass spectrometry (TOF-SIMS) depth profiling, and FIB - helium ion scanning microscope (HIM) imaging to detail the structural and compositional changes associated with Na/Na+ charging/discharging of 50 and 100 nm thin films of Sb. TOF-SIMS on a partially sodiated 100 nm Sb film gives a Na signal that progressively decreases towards the current collector, indicating that sodiation does not proceed uniformly. This heterogeneity will lead to local volumetric expansion gradients that would in turn serve as a major source of intrinsic stress in the microstructure. In-situ TEM shows time-dependent buckling and localized separation of the sodiated films from their TiN-Ge nanowire support, which is a mechanism of stress-relaxation. Localized horizontal fracture does not occur directly at the interface, but rather at a short distance away within the bulk of the Sb. HIM images of FIB cross-sections taken from sodiated half-cells, electrically disconnected and aged at room temperature, demonstrate non-uniform film swelling and the onset of analogous through-bulk separation. TOF-SIMS highlights time-dependent segregation of Na within the structure, both to the film-current collector interface and to the film surface where a solid electrolyte interphase (SEI) exists, agreeing with the electrochemical impedance results that show time-dependent increase of the films’ charge transfer resistance. We propose that Na segregation serves as a secondary source of stress relief, which occurs over somewhat longer time scales.

Professor Mario Wreidt (left) and Professor David Mitlin