Host: Nikolai DeMartini
The building blocks of cellulose microfibrils, which make up the wall of wood fibers, are cellulose nanofibrils (CNF). These fibrils are several microns long and have a diameter of about 5 nm. They consist of alternating crystalline and amorphous regions, each about 100-200 nm in length. Two forms of nanocellulose can be obtained from CNF: 1) cellulose nanocrystals (CNC), which can be obtained by removing the amorphous regions by acid hydrolysis, resulting in needle-like particles, each about 100-200 nm long and 5 nm wide, which are well studied and presently available commercially; and 2) hairy nanocellulose (HNC), the topic of this talk.
Instead of hydrolysis, we can cleave the chains in the amorphous regions, resulting in cellulose nanoparticles with a crystalline core, with amorphous cellulose chains protruding from both ends. We refer to these particles as hairy nanocellulose (HNC). We can adjust the length of the hairs by acid hydrolysis. The hairs (i.e. the protruding chains) can be readily functionalized by reactive aldehyde groups, carboxyl groups, quaternary amine groups, and as a result the properties of HNC can be precisely tuned. When charged, they can be readily dried and redispersed, in contrast with CNC, which is difficult to redisperse when dried. We will discuss the synthesis of these particles, their characterization and rheological properties, and point to a number of potential applications, such as heavy metal scavenging, antiscaling agents, antifouling membranes, crystal morphology modifiers, components of wound dressings and when incorporated in carbon nanotubes matrices, they act as a humidity switch.
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Theo van de Ven received a Masters Degree in Physical and Colloid Chemistry, with a minor in Theoretical Physics, from Utrecht University in the Netherlands and a PhD in Physical Chemistry from McGill University. After a two-year postdoc at Sydney University in Australia, he returned to Montreal, where he became an assistant scientist at Paprican, working in the Pulp & Paper Centre, McGill. In 1981 he obtained a cross-appointment with the Department of Chemistry, where he became a full professor in 2004. Presently he holds the Sir William C. Macdonald Chair in Chemistry, Department of Chemistry, McGill and is Co-director of QCAM (Quebec Centre for Advanced Materials). He has published over 350 papers in scientific journals, 64 refereed conference proceedings, 7 book chapters, 1 book, edited 4 books and holds 4 patents. His research interests are in the areas of colloidal hydrodynamics, papermaking and cellulose chemistry. He is a Fellow of the Royal Society of Canada, was awarded the ACS Award in Colloid and Surface Science, and received the Kalev Pugi Award from the Canadian Section of the Society of Chemical Industry. He recently received the Bates S. Gold Memorial Medal, the highest distinction in Canada for the advancement of science and technology in the Forest and Pulp and Paper Industry.
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Dr. Laura de Vito
Research Fellow, Air Quality Management Resource Centre
Faculty of Environment and Technology, University of the West of England
Despite many years of efforts to reduce air pollution to safe ambient concentrations, levels of several pollutants still contravene health-based guidelines across many European cities and around the world. During this seminar I will draw from evidence across six European cities as part of the ClairCity project and from Delhi as part of the CADTIME project to show why and how air quality management should put a greater emphasis on the social and contextual factors that contribute to emissions. By putting citizens’ behaviour, activities and experiences of air pollution at the heart of policymaking, citizens are empowered to visualise clean, low carbon, healthy futures for their city and policymakers can design context-specific policies that work and produce meaningful results for all communities.
Download the seminar poster HERE
Dr. Daniel Siegwart
Department of Biochemistry
University of Texas Southwestern Medical Center
Structure‐guided, rational optimization of nanoparticle carriers for delivery of long RNAs to achieve CRISPR/Cas gene editing and mRNA-mediated protein replacement will be described. CRISPR/Cas is a revolutionary gene editing technology with wide-ranging utility. We will present and report the development of zwitterionic amino lipids (ZALs) that are uniquely able to deliver long RNAs (Cas9 mRNA and targeted sgRNA) from ZAL nanoparticles (ZNPs) to enable gene editing. ZALs were synthesized using high efficiency ring-opening and addition reactions, providing access to a library of unique charge unbalanced lipids. Intravenous co-delivery of Cas9 mRNA and sgLoxP induced expression of floxed tdTomato in the liver, kidneys, and lungs of genetically engineered mice. Correction of a mutation causing Duchenne muscular dystrophy (DMD) via an exon skipping approach will be highlighted as a functional application of CRISPR/Cas in muscle. The effectiveness of ZNPs for delivery of long RNAs provides a chemical guide for the rational design of future carriers. Such insights allowed reengineering of dendrimer-based lipid nanoparticles (DLNPs) for mRNA-based protein replacement therapy, where mDLNPs effectively delivered fumarylacetoacetate hydrolase (FAH) mRNA that normalized liver function and significantly extended survival in a difficult‐to‐treat Hepatorenal Tyrosinemia Type I (HT‐1) mouse model. The development of gene editing using synthetic nanoparticles is a promising step towards improving the safety, efficacy, and utility of CRISPR/Cas.
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Dr. Daniel J. Siegwart is an Associate Professor in the Department of Biochemistry at UT Southwestern Medical Center. He received a B.S. in Biochemistry from Lehigh University (2003), and a Ph.D. in Chemistry from Carnegie Mellon University (2008) with University Professor Krzysztof Matyjaszewski. He also studied as a Research Fellow at the University of Tokyo with Professor Kazunori Kataoka (2006). He then completed a Postdoctoral Fellowship at MIT with Institute Professor Robert Langer (2008-2012). The Siegwart Lab aims to discover and define the critical physical and chemical properties of synthetic carriers required for therapeutic delivery of small (e.g. ~22 base pair miRNA) to large (e.g. ~5,000 nucleotide mRNA) RNAs. Their research is grounded in chemical design and takes advantage of the unique opportunities for collaborative research at UT Southwestern.
Hosted by Dr. Molly Shoichet
Snacks and Refreshments will be served
Co-hosted with the Institute for Water Innovation (IWI)
Host: Vladimiros Papangelakis
Plastic debris and in particular secondary microplastics represent a significant problem among the various pollution problems facing the marine environment. Several studies have been conducted on the fate and weathering of plastics in the marine environment including the generation and fate of microplastics. Laboratory results on the biodegradation of plastics show great variability. An important question, which remains unanswered, is what is the level of weathering that makes the common plastics (C-C backbone) biodegradable at a reasonably fast rate. In this presentation we focus on the determination of biodegradation and fragmentation rates of polystyrene and polyethylene films naturally weathered on beach sand as well as polypropylene films weathered in seawater mesocosms. Their fate in the water column is also examined. Overall, the results are very encouraging pointing to new challenges that need to be addressed for a successful biodegradation of plastics in the marine environment as well as significant advances in the context of circular economy. The most effective mitigation measures and plastic debris removal technologies from the marine environment will also be highlighted.
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Nicolas Kalogerakis is Professor of Biochemical Engineering at the Technical University of Crete (Greece) where he has served as Vice-President of the University Council and as Department Head (twice). Prior to that he was a Professor at SUNY-Buffalo (USA) and at the University of Calgary (Canada). He holds a Diploma in Chemical Engineering from NTUA (Athens), an MEng from McGill University and a PhD from the University of Toronto. His area of expertise includes environmental biotechnology focusing on bioremediation and phytoremediation technologies for the restoration of contaminated sites; protection and restoration of the marine environment; novel oxygenation systems and wastewater treatment; and mathematical modeling of environmental processes. Currently his group is participating in several National projects and 4 EU-funded research projects (H2020) and he was the coordinator of the large FP7-project KILL*SPILL. Prof. Kalogerakis’ publication record includes five patents, one book, 188 papers in referred journals and more than 170 presentations at international conferences including several keynote and plenary presentations. He has >8100 citations with a H-index of 47 (Scopus). He has served as a member of the European Commission Environment Committee (2007-2011) and as Sherpa at the European Commission High Level Group on Key Enabling Technologies (2013-2015).
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Irving O. Shoichet Distinguished Lecture
Host: Molly Shoichet
Our laboratory studies how micro- and nanoscale systems can be deployed to understand, diagnose, and treat human disease. In this talk, I will describe our progress in two application areas: liver disease and cancer. In the area of hepatic tissue engineering, we are developing microtechnology tools to understand how ensembles of cells coordinate to produce tissues with emergent properties in the body. We have used this understanding to fabricate human microliver tissues in both ‘2D’ and ‘3D’ formats that enable us to study the pathogenesis drug-drug interactions, hepatotropic pathogens, and regeneration.
In the area of cancer, we are developing nanotechnology tools to meet the challenge of delivering cargo into the tumor microenvironment where transport is dominated by diffusion. Our strategy is to design nanotechnologies which emulate nature’s mechanisms of homing, activation, and amplification to deliver cytotoxic drugs, diagnostic tools, imaging agents, and siRNA to tumors. Thus, using nature as a guide, we are establishing a framework for building systems from micro- and nanoscale components that function collectively to treat human disease.
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Sangeeta Bhatia is a biomedical researcher, MIT professor, and biotech entrepreneur who works to adapt technologies developed in the computer industry for medical innovation. Trained as both a physician and engineer at Harvard, MIT, and Brown University, Bhatia leverages ‘tiny technologies’ of miniaturization to yield inventions such as human microlivers that model human drug metabolism and liver disease, as well as responsive nanoparticles and nanoporous materials that can be engineered to diagnose, study, and treat a variety of diseases, including cancer. She and her trainees have launched multiple biotechnology companies to improve human health. As a prolific inventor and passionate advocate for diversity in science and engineering, Bhatia has received many honors including the Lemelson-MIT Prize, known as the ‘Oscar for inventors,’ and the Heinz Medal for groundbreaking inventions and advocacy for women in STEM fields. She is a Howard Hughes Medical Institute Investigator, the Director of the Marble Center for Cancer Nanomedicine at the Koch Institute for Integrative Cancer Research at MIT, and an elected member of the National Academy of Sciences, the National Academy of Engineering, the American Academy of Arts and Science, the National Academy of Inventors, and Brown University’s Board of Trustees.
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Joel Corbin, PhD
Research Officer, Metrology Research Centre National Research Council Canada
The combustion of carbonaceous fuels emits radiation-absorbing gases and particles, including but not limited to soot. These emissions play a major role in climate forcing. For example, mean global forcing by soot approaches that by CO2 and regional forcing by soot can exceed that of CO2. Yet recent work has recognized the role of other forms of carbon, such as small light-absorbing molecules (brown carbon) and light-absorbing macromolecules (tarballs).
Particle deposition on glaciers and snow further accelerates their melt. In order to understand the environmental effects of these materials, their fundamental properties must be understood, as these influence their atmospheric impacts, particularly their radiative forcing, and their deposition rates, resulting for example in the darkening of glaciers and snow. This talk will discuss the chemical nature of these light-absorbing carbons as well as physical models for their optical properties. The determination of accurate optical models is surprisingly difficult, and leads to the conclusion that the relative importance of non-soot aerosols can be surprisingly high.
Techno-economic analysis (TEA) integrates process design and economic analysis techniques to assess the commercial viability of production processes. Understanding TEA is fundamental for researchers developing novel production methods and pathways.
Workshop topics will include:
•Process design fundamentals
•Lab data for TEA and scale-up
•Economic analysis tools for talking to industry
•Estimating product price and feedstock costs
•Cap-Ex, Op-Ex and project financing
•Technology commercialization
•Presentations by industry partners
The workshop will focus on biotechnology applications.
Allison Simmonds is a Professional Engineer with a Master’s degree in Chemical Engineering from the University of Toronto. She has more than 10 years of experience in environmental consulting, including 6 years working at the interface between research and industry with Savant Technical Consulting. Her expertise includes bioprocess engineering, techno-economic analysis, bioinformatics, bioremediation and site assessment, and life cycle assessment.
Lunch will be served so please register if you plan to attend: https://www.eventbrite.ca/e/techno-economic-analysis-primer-workshop-registration-77175019561
Prof. Paschalis Alexandridis
University at Buffalo
Block copolymers exhibit an innate ability to organize from the nanoscale across to the mesoscale. Selective solvents provide valuable degrees of freedom for controlling the morphology and, hence, structure/property relationships; furthermore, solvents can dramatically affect the molecular mobility and the dynamics of structural transformations. The presentation will utilize research findings on “model” amphiphilic block copolymers of the poly(ethylene oxide)-poly(propylene oxide) (PEO-PPO) family, commercially available as Pluronics or Poloxamers, to discuss: (1) the basic self-assembly elements, i.e., micelles, in terms of the thermodynamics and interactions underlying their formation and disassembly in aqueous solvents (selective for PEO), and their nano-scale structure and dynamics, (2) the adsorption of block copolymers on surfaces macroscopic and nanoscale, hard and soft, and how the adsorbed layer structure can be related to the polymer organization in the bulk solution, (3) ordered micelles, i.e., lyotropic liquid crystal structures, in the context of their range of stability as affected by the block copolymer conformation and various additives (e.g., glycols, nanoparticles), and their structural transformations under shear, and (4) how the equilibrium phase behavior can inform processing paths for the preparation of kinetically stabilized emulsions and nanoparticles, and templates for nanomaterials synthesis. The self-assembly properties of PEO-PPO block copolymers in selective solvents are compared to those of low-molecular weight nonionic surfactants, and to block copolymers organizing in the absence of solvents.
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Paschalis Alexandridis utilizes molecular interactions and supramolecular assemblies to develop products with desired properties and function, and processes that are environment friendly and energy efficient. Ongoing projects address structuring via self-assembly and directed assembly, block copolymers, perfluorinated surfactants, ionic liquid solvents, polymer dissolution, biomass processing, and plastics recycling. He has worked with industry to address product and process issues involving complex fluids, soft materials, and surfaces, for example, formulation of waterborne inks for improved pigment deposition, prediction of long-term performance of biomedical cross-linked polymer gels, and control of adhesion during plastics processing.
Prof. Alexandridis has authored over 165 peer-reviewed articles (published in 60 different journals) and 65 proceedings (Google Scholar citations >17,400 and h-index = 67). He is the editor of two books and co-inventor of six U.S. patents on pharmaceutical formulations, superabsorbent polymers, and nanomaterial synthesis. He has served as Director of Graduate Studies in Chemical Engineering, Co-Director of the Materials Science and Engineering program, and Associate Dean for Research and Graduate Education in the School of Engineering and Applied Sciences. Alexandridis received his PhD in chemical engineering from MIT in 1994, and joined UB in 1997 following postdoctoral research in polymer and surfactant physical chemistry at Lund University in Sweden.
At UB, Alexandridis has developed and taught courses such as “We All Live in a Material World” and “Molecular Nanotechnology and Bionanotechnology” (freshman-level seminars), “Colloid and Surface Phenomena”, “Introduction to Polymers”, and “Petroleum Engineering” (elective courses), and “Product Design” (required capstone design course). He has mentored in research over 70 graduate and 70 undergraduate students.
Prof. Alexandridis is an elected Fellow of the American Institute of Chemical Engineers (AIChE) and the American Association for the Advancement of Science (AAAS). He has received numerous awards including the American Chemical Society (ACS) Schoellkopf Medal, Bodossaki Foundation Academic Prize in Applied Science, SUNY Chancellor’s Awards for Excellence in Scholarship and Creative Activity and in Teaching, and UB’s inaugural Excellence in Graduate Student Mentoring Award. Alexandridis has served as chair of AIChE Area 1C: “Interfacial Phenomena” and on the executive committee of the ACS Division of Colloid and Surface Chemistry. He is currently serving as co-Editor-in-Chief of the International Journal of Molecular Sciences and Review Editor of the Journal of Surfactants and Detergents.
We all need food – so that we don’t go hungry, stay fit, active and healthy through our lives. But if the food we consume doesn’t contain essential vitamins and minerals, that our bodies need on a daily and consistent basis – we will never reach our full potential. One in three of us do not get enough micronutrients to survive and thrive. In large parts of South Asia and sub Saharan Africa, more than half of all mothers and young children are anemic and iron/folate deficient compromising their health and survival and the lives of their children.
Research at the Department of Chemical Engineering, University of Toronto spanning nearly two decades has enabled us to develop a cost-effective and sustainable means of ensuring that people living in all regions of the world receive their micronutrients through table salt. Our work covered basic research, stability, consumer acceptability and efficacy testing and scale up to commercial levels. For just 25 cents per person per year it is now possible to add micronutrients like iron, folic acid, vitamin B12 and zinc (in shelf stable and efficacious forms) to salt.
Over the past 20 years salt containing added iodine has steadily reached nearly 5 billion people virtually eliminating iodine deficiency worldwide. Building on this infrastructure, multiple nutrient salt can aim to cover the same populations quickly, consistently and sustainably – contributing to reduction in maternal and young child mortality, better health and growth, increased work productivity and earnings – the real development bargain of the 21st Century!
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Venkatesh Mannar is a technology leader who has pioneered effective international nutrition initiatives focused on the world’s most vulnerable citizens. As President of the Micronutrient Initiative Canada (MI) headquartered in Ottawa for nearly 20 years till 2014, he played a major role in the development and expansion of health and nutrition programmes to address hidden hunger globally.
Mannar currently divides his time between India, Canada and the United States. He serves as a Special Adviser on Nutrition to the Tata Trusts and The Tata Cornell Agriculture & Nutrition Initiative. He pursues his research and teaching interests through appointments with the Centre for Global Engineering, Faculty of Engineering & Applied Science, University of Toronto and the Division of Nutritional Sciences, Cornell University. He has co-authored more than 100 articles in leading journals and is the co-editor of ‘Food Fortification in a Globalized World’. Mannar and his co-researchers have developed cutting-edge technologies to enhance the nutritional quality of foods.
Mannar has been appointed an Officer of the Order of Canada, one of the country’s greatest civilian honours, for his leadership in the global fight against malnutrition and micronutrient deficiency. He was also conferred with an Honorary Doctor of Science Degree by the University of Toronto.
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Jay G. Slowik
Research Scientist, Laboratory of Atmospheric Chemistry
Paul Scherrer Institute Switzerland
Mass spectrometry is a powerful tool for the analysis of aerosol composition. However, tradeoffs typically exist between the loss of chemical information due to thermal decomposition and/or ionization-induced fragmentation on the one hand, and lower time resolution and/or separated collection/analysis stages on the other. We address these issues through the development of an extractive electrospray ionization time-of-flight mass spectrometer (EESI-TOF), which provides online, highly time-resolved measurements of aerosol composition without significant decomposition or fragmentation. Further, the EESI-TOF provides a versatile sampling/ionization framework, as by simply changing the composition of the primary spray and mass spectrometer polarity, the instrument can be configured to optimize detection of different organic fractions or water-soluble metals, while the sampling inlet can be configured to allow separate detection of the gas and particle phase. Two applications of the EESI-TOF are presented. First, we demonstrate rapid intra-particle decomposition reactions in secondary organic aerosol generated from the dark ozonolysis of α-pinene, as well as further reaction on the exposure of the aerosol to visible light. Second, we explore the sources and processes governing SOA composition in complex urban environments.