Environmental Science: Nano Blog

Quin Miller is a Research Scientist (Chemist) at Pacific Northwest National Laboratory (PNNL) in Richland, WA, USA. After completing his Geology undergraduate studies at Whitman College in Walla Walla, WA, Quin worked at PNNL as a geochemistry post-bachelor’s research associate under the mentorship of Senior Research Scientist Todd Schaef. Quin then continued his studies for his Geology PhD at the University of Wyoming under the supervision of Prof. John Kaszuba, conducting dissertation research on the “Geochemistry of Multiphase CO₂-H₂O-Rock Interactions in Nanoconfined Environments.” During his PhD studies, he returned to PNNL on several occasions as a visiting researcher and also spent four months working with Dr. Gernot Rother at Oak Ridge National Lab via the Department of Energy Office of Science Graduate Research (SCGSR) Fellowship program. After completing his PhD in August 2017, Quin spent two years as a PNNL geochemistry postdoctoral research associate expanding his experimental, analytical, and professional skillsets under the guidance of Todd Schaef and Laboratory Fellow Dr. Kevin Rosso. In 2019, Quin was recognized with an Outstanding Postdoc Award for exceptional contributions to PNNL, with the nomination criteria including productivity, innovation, dedication, hard work, and strong sponsor impact/visibility. Quin was also elected to the Clay Minerals Society Council for the 2020-2022 term, and recently received a 2020 PNNL Outstanding Performance Award for laboratory safety.

Read Quin Miller’s Emerging Investigator Series article “Emerging investigator series: ion diffusivities in nanoconfined interfacial water films contribute to mineral carbonation thresholds” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on Ion Diffusivities in Nanoconfined Interfacial Water Films Contribute to Mineral Carbonation Thresholds. How has your research evolved from your first article to this most recent article?

I was fortunate to find a great mentor early in my research career, Todd Schaef, who emphasized the importance of continuing my education, setting measurable goals, assembling a strong research team, and producing focused, data-driven manuscripts. When I wrote my first research paper during my post-bachelor’s research position, my primary concerns were learning to complete an investigation, navigate the publishing process, and having a finished product to show to graduate programs. As my graduate studies progressed and I worked to pin down the scope of my dissertation, my advisor, Professor John Kaszuba, reminded me that many highly technical pursuits aren’t just missing the forest for the trees, but missing the forest for the leaves. I also credit John for giving me a lot of latitude to explore ideas and for greatly influencing my writing and thinking styles, including a willingness to get excited about both the big idea and the associated minutiae.

These days, I continue to work with collaborators to probe interfacial processes with PNNL’s world-unique high-pressure experimental suite, including in situ X-ray diffraction, infrared spectroscopy, and nuclear magnetic spectroscopy. I am also fortunate to be working on a broader range of projects led by Laboratory Fellow Dr. Pete McGrail that include subsurface sensing technology R&D and planned field deployments. I am also able to work more closely with staff from PNNL’s Environmental Molecular Sciences Laboratory (EMSL) user facility, including Dr. Mark Bowden. Importantly, as we demonstrate in our present Environmental Science: Nano article, molecular modelling insights from Dr. Sebastien Kerisit are providing vital molecular-scale insight into reaction mechanisms and processes observed via experiment. This type of experimental/theoretical crosscut is a signature strength of PNNL’s Basic Energy Science Geochemistry program that is led by Dr. Kevin Rosso.

What aspect of your work are you most excited about at the moment?

I am most excited about collaboration opportunities and working with investigators with a diversity of backgrounds, ideas, and research interests. It’s exciting to be at the early stages of a career, surrounded by a vibrant mix of established and early-career researchers. I also looks forward to staying diversified enough that I will someday be tackling problems with scientists that have yet to be born and AI collaborators that have not yet come online. In the short term, I will be co-mentoring two students this summer. I am also excited about the continuing development of our laboratory-based in situ X-ray diffraction capability that will enable us to probe an expanded pressure-temperature-composition space and work with a greater variety of samples. Research conducted with this capability will support several PNNL and DOE programs, including those concerned with nucleation and growth of applied functional materials like metal-organic frameworks and atomically-precise heterostructures. Todd Schaef and I are always interested in new collaborations to take advantage of our “24/7” beamtime with our current setup.

In your opinion, what are the most important questions to be asked/answered in this field of research?

The most important questions concern how to successfully connect disparate spatial and temporal scales, as quantifying ephemeral atomic- to molecular-scale phenomena is vital to understanding coupled societal- and planetary-scale processes whose ebbs and flows will outlast us all. For example, how do we take molecular-scale insights about interfacial mineral carbonation and clay mineral swelling and use this information to not only predict but control the fate and transport of CO₂ in a geologic carbon or hydrocarbon reservoir? Successful bridging between of fundamental and applied science will by absolute necessity involve interdisciplinary collaboration. For instance, a research frontier I am excited to explore concerns coupled geochemical, geophysical, and geomechanical phenomena at the nanoscale, which have outsized yet poorly-understood influences on subsurface energy storage and extraction.

What do you find most challenging about your research?

My biggest challenge is finding time to explore all of the ideas that interest me and choose which ones to pursue in depth! Partly it’s a classic, age-old problem: it’s a lot easier to collect data than to process, interpret, and publish it.

In which upcoming conferences or events may our readers meet you?

Given this worldwide health crisis, nothing is set in stone for my conference schedule. I hope everyone can be as healthy, safe, and united as possible during this difficult time. I was scheduled to present at the Spring American Chemical Society Meeting (Philadelphia, PA) on March 25^th, but it has been cancelled due to the global COVID-19 outbreak. I plan to present at the June 15-19 Clay Minerals Society meeting to be held at PNNL (Richland, WA), and the abstract deadline for that meeting is March 15^th. I am also co-chairing a session at the June 21-26 Goldschmidt 2020 geochemistry conference in Honolulu, HI and will also present at the Unconventional Resources Technology Conference (URTeC), which will be held in Austin, TX from July 20-22. In August I plan on presenting at the Department of Energy Carbon Storage project review meeting (Pittsburg, PA) and the Fall ACS meeting (San Francisco, CA), finally wrapping up the calendar year with the December 7-11 American Geophysical Union annual meeting in San Francisco, CA.  I may also be reached via quin<dot>miller<at>pnnl.gov and @quinmiller.

How do you spend your spare time?

I enjoy hiking, skiing, tennis, and reading.

Which profession would you choose if you were not a scientist?

If I weren’t working as a scientist, I would choose a field that promoted curiosity and inquiry about the natural world and our place in it. I would also enjoy working in an emerging markets startup and getting to interact with movers and shakers from around the globe and assist them in connecting ideas, institutions, and researchers.

Can you share one piece of career-related advice or wisdom with other early career scientists?

Never underestimate the power of small habits.

Chamila Gunathilake is currently working as a Senior Lecturer in the Department of Chemical and Process Engineering, at the University of Peradeniya. He received his bachelor’s degree in Chemistry from the University of Peradeniya, Sri Lanka. He completed his Ph.D. in Nano Science and Engineering at KSU,  OH, USA. His current work focuses on the development of nanoporous and mesoporous carbon silica materials with organic pendant and bridging groups and incorporated metal (aluminum, zirconium, calcium, and magnesium) species for low, ambient, and high-temperature carbon dioxide (CO₂) sorption, phosphorous-hydroxy functionalized mesoporous silica materials for water treatment, and amidoxime-modified ordered mesoporous silica materials for uranium sorption under seawater conditions. He has so far received nine awards including three ACS awards: ACS-(Industrial & Chemical Engineering Graduate Student Symposium Award for the year 2015 (ACS 250) and 2016 (ACS 252) and ACS Environmental Chemistry Student Award for the year 2016 (ACS 251) and Presidential Award for Scientific Publication in 2019. His academic career has resulted in approximately 30 publications and 44 international conference papers holding an H factor of 20 and an I-10 index of 15. (ACS-American Chemical Society)

Read Chamila Gunathilake’s Emerging Investigator Series article “Emerging investigator series: Synthesis of Magnesium Oxide Nanoparticles Fabricated on Graphene Oxide Nanocomposite for CO2 Sequestration at Elevated Temperatures” and read more about him in the interview below:

Recent Emerging Investigator Series paper focuses on Synthesis of Magnesium Oxide Nanoparticles Fabricated on Graphene Oxide Nanocomposite for CO₂ Sequestration at Elevated Temperatures. How has your research evolved from your first article to this most recent article? 

My first paper, Mesoporous organosilica–alumina composites and their thermal treatment in nitrogen for carbon dioxide sorption at elevated temperatures, was emerged from grad life. During my graduate research life, I have experienced with various metal-organic frameworks (MOF) synthesis, surface characterization, and assembly of nanoscale materials and methods to integrate nanomaterials with other materials via polymer assisted self-assembly process for environmental and catalytic applications, including high-temperature carbon dioxide (CO₂) sequestration from power plant, treatment of wastewater streams, uranium extraction from seawater. Grad life is the best moment in my life, and it paved the way to increase my boundaries of thought, where I felt my capacity to do something fascinating is still undiscovered inside. This is the first time I worked with graphene and graphene oxide that blended with magnesium to produce nanocomposites and applied to high-temperature CO₂ sorption. I obtained impressive results that are highly comparable to the materials I have studied in the past that led to thirtieth publications in 2020.

What aspect of your work are you most excited about at the moment?

At the moment, I am interested in designing novel sorbents for polluted water treatment and uranium extraction from seawater. As you know water is essential for life on earth, and consequently, it must be obtained in pure form. Water pollution problems are most serious in large cities in developing countries like my mother country, Sri Lanka. Currenntly, many people are suffering from kidney disease caused by heavy metals and I am trying to find an alternative solution to resolve this issue. Testing specific surface-functionalized mesoporous silica materials for uranium sorption under seawater conditions is another interesting project. Although the concentration of uranium in seawater is only about 3 ppb, a gigantic volume of all oceans (about 1.37 billion Km³) contains about 4.5 billion tons of uranium. I would say, if we can recover only 50 % of this resource, it would be enough to upkeep nuclear reactors worldwide for about 6,500 years. Among many actinide elements, uranium is the major and common fuel for nuclear reactors. Thus, there is a great interest in extracting uranium from seawater and use it as an alternative sustainable energy source. The final goal is to design composite materials with desired porosity, surface area, and functionality by selecting proper metal oxide precursors, organosilanes, and block copolymer templates and by adjusting synthesis conditions for the aforementioned applications

In your opinion, what are the most important questions to be asked/answered in this field of research?

Uranium extraction from seawater, I believe the most pressing question would be, how can we increase the adsorption capacity and rate of adsorption of uranium with the designed material. Typically to extract 1 Kg of yellow uranium cake, the average submerging time of the sample is six months. Moreover, it is necessary to know how to overcome issues such as handling nanomaterials in seawater and accessing a large amount of seawater for given materials. 

Regarding the application of CO₂ sorption, there has been an issue to apply those materials under practical operating conditions. Thus, I believe the requirement of proper engineering design and studying recycle stability and reusability studies is mandatory.

What do you find most challenging about your research?

Any person would love to feel the pristine nature of the environment than a grimy one. We as chemical engineers/ chemists are the major stakeholders responsible for making the planet earth free of venomous debris. So, I firmly believe that it is our responsibility to give back mother nature and its’ glory again. We will be able to rectify at least some percentage of mistakes committed by our own by doing so. I do feel emphasis shown towards the environment should be more and we should be at the forefront of educating the community. I feel that science & engineering helps me to better understand issues regarding carbon dioxide capture, wastewater treatment, uranium extraction, and gives me a chance to make the earth a better place to live. However, getting at the heart of any research question in the Environmental field requires extensive knowledge in other fields. Sometimes, I wish I could have another graduate degree in Environmental, Polymer and Chemical engineering all at once to understand just one piece of the puzzle. Extending into literature outside my comfort zone is always challenging.

In which upcoming conferences or events may our readers meet you?

I will be in Nano 9, a conference in Poland in September where my graduate advisor holds a co-chair position in Nano 9. 

How do you spend your spare time?

I enjoy spending time with my staff members, friends, and family members. I most of the time willing to help people who essentially need our hand to live. Outside the academic work, I mostly preferred for traveling through nature made aesthetic places. Most of the spare time, I listen to music and play sports. 

Which profession would you choose if you were not a scientist?

If I were not in academics, I always thought that I’d like to be a travelling guide who helped tourists to travel throughout my small country. 

Can you share one piece of career-related advice or wisdom with other early-career scientists?

At different stages of life, we are working on different efficiencies. In case one stage fails, you can turn your life into a better place in the next stage. So, for early-career scientists, I would recommend collaborating strategically with people from different fields and developing your unique research brand. While working with them, learn a lot about teamwork, learn how to interact with different people and share your skills with them. Participate in national and international oral and poster presentations, present your research, encounter cutting-edge science of different fields, hear the latest information in your areas of professional interest, and network with colleagues.

We are delighted to share with you a selection of high-impact papers by Emerging Investigators in the field of environmental science and engineering. These papers, published in Environmental Science: Nano as well as our sister journals Environmental Science: Processes & Impacts, and Environmental Science: Water Research & Technology, showcase the breadth of exciting research being conducted by rising stars in our field.

The latest work from rising stars of environmental science

Emerging investigator series: towards a framework for establishing the impacts of pharmaceuticals in wastewater irrigation systems on agro-ecosystems and human health
Laura Carter et al

Emerging investigator series: spatial distribution of dissolved organic matter in ice and at air–ice interfaces
Tara Kahan et al

Emerging investigator series: atmospheric cycling of indium in the northeastern United States
Sarah Jane White et al

Emerging investigator series: transformation of common antibiotics during water disinfection with chlorine and formation of antibacterially active products
Olya Keen et al

Emerging investigator series: photocatalysis for MBR effluent post-treatment: assessing the effects of effluent organic matter characteristics
Samuel Snow et al

Emerging investigator series: treatment and recycling of heavy metals from nanosludge
Jing Zhang et al

Emerging investigator series: characterization of silver and silver nanoparticle interactions with zinc finger peptides
Korin Wheeler et al

Emerging investigator series: protein adsorption and transformation on catalytic and food-grade TiO₂ nanoparticles in the presence of dissolved organic carbon
Kyle Doudrick et al

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The RSC’s Emerging Investigator Series provides a unique platform for early-career environmental scientists & engineers to showcase their best work to a broad audience. Contact us to apply for consideration in this Series. To be eligible, you will need to have completed your PhD (or equivalent degree) within the last 10 years†, have an independent career and appear as corresponding author on the manuscript.

Across the environmental science journals, the Emerging Investigator Series is curated by our Series Editors; David Cwiertny, Jeremy Guest, Long Nghiem, Ligy Philip, Delphine Farmer, Lenny Winkel, Guang-Guo Ying and Peter Vikesland.

Read more of our Emerging Investigator Series papers using the links below.

Environmental Science: Nano Emerging Investigator Series

Environmental Science: Processes & Impacts Emerging Investigator Series

Environmental Science: Water Research & Technology Emerging Investigator Series

Also, read the latest interviews with our Emerging Investigators to find out more about their work and the important research challenges that they are tackling.

We hope you enjoy reading these papers from future leaders in the field of environmental science.

†Appropriate consideration will be given to those who have taken a career break or followed a different study path

Dr. Stacey Louie is an Assistant Professor in the Department of Civil and Environmental Engineering at the University of Houston. She received her Ph.D. from Carnegie Mellon University in 2014 and conducted a U.S. National Research Council (NRC) postdoctoral fellowship at the National Institute of Standards and Technology (NIST) – Gaithersburg from 2014 to 2016. Her research covers the environmental implications and applications of inorganic and polymeric nanomaterials, with a specific focus on developing approaches to characterize the dynamic interactions of nanomaterials with small molecules, natural organic matter, and biomolecules and the effects of organic surface coatings on their aggregation, transport, and reactivity. She seeks to apply suites of characterization tools to gain a mechanistic understanding of the fate and behavior of nanomaterials in complex media in both natural environments and engineered systems.

Read Stacey Louie ’s Emerging Investigator Series article “Polymeric Nanocarriers for Agricultural Applications: Synthesis, Characterization, and Environmental and Biological Interactions” and read more about her in the interview below:

Your recent Emerging Investigator Series paper focuses on Polymeric Nanocarriers for Agricultural Applications: Synthesis, Characterization, and Environmental and Biological Interactions. How has your research evolved from your first article to this most recent article?

My prior research as a Ph.D. student was focused on the influence of natural organic matter surface coatings on nanoparticle aggregation and transport behaviour. During my postdoctoral research at the National Institute of Standards and Technology (NIST), I was fortunate to have the opportunity to learn more advanced methods to characterize the chemistry of organic surface coatings on nanoparticles and their transformations. This focus on the organic-nanoparticle interactions led to my current interests in expanding to polymeric nanoparticles along with inorganic nanoparticles, and the skills gained through my Ph.D. and post-doc experiences have been invaluable to be able to probe nanomaterial properties and behaviours in complex media.

What aspect of your work are you most excited about at the moment?

My research involves evaluating dynamic nanoparticle interactions in complex media, from surface transformations and reactivity to release of active ingredients from polymeric nanoparticles. I enjoy projects where many components are interacting in the sample such that there is a real need to apply a multitude of complementary characterization tools. In my recent and current projects, I have found that the results of initial experiments in these complex samples can seem confounding or even contradictory, but with additional characterization tools applied, at some point all of the results are found to converge to one consistent and logical story of how the nanoparticle is behaving. It is satisfying to finally gather enough information to make the transition from confusion to understanding.

In your opinion, what are the most important questions to be asked/answered in this field of research?

Developing quantitative structure-activity relationships to predict nanomaterial behaviour in natural environments will be important but very challenging. Small-scale laboratory studies that identify mechanisms for nanomaterial behaviours may not translate to more complex systems, and we need to identify which properties of the nanomaterial and its environment are ultimately critical to predict its behaviour and which become relatively insignificant.

What do you find most challenging about your research?

Nanomaterials can participate in a wide variety of processes (dissolution, aggregation, surface transformations, reactions, etc.) that are often highly sensitive to the surrounding conditions. Being able to selectively probe one or two specific processes while controlling for others can be difficult or infeasible. For example, specifically identifying the effect of an adsorbed surface coating on nanoparticle reactivity is difficult when the surface coating also changes the nanoparticle aggregation behaviour. It can be challenging to determine whether it is worthwhile to continue attempting to optimize experimental conditions or whether a feasibility limit has been reached.

In which upcoming conferences or events may our readers meet you?

I will likely attend the GRC on Nanotechnology for Agriculture and Food, as well as the Sustainable Nanotechnology Organization (SNO) conference in 2020.

How do you spend your spare time?

I enjoy knitting, sewing, and community gardening but rarely have time to work on any projects lately. I also enjoy music and video games and do still attend concerts on occasion.

Which profession would you choose if you were not a scientist?

I might be working at a garden center, a video game journalist, or perhaps a librarian/archivist.

Can you share one piece of career-related advice or wisdom with other early career scientists?

I think understanding your own specific skill set is important, so that you can identify what projects you are best suited to tackle or where your skills can contribute toward collaborative projects. An external perspective can be helpful to figure this out.

Dr. Xing Xie is an assistant professor and the Carlton S. Wilder Junior Professor in the School of Civil and Environmental Engineering at Georgia Institute of Technology. Prior to joining Georgia Tech, he was a postdoc at California Institute of Technology in 2014-2017. Dr. Xie received his B.S. (2006) and M.S. (2008) degrees in Environmental Science & Engineering from Tsinghua. He received his Ph.D. degree (2014) in Civil & Environmental Engineering and his second M.S. degree (2012) in Materials Science & Engineering from Stanford University. He has been applying environmental biotechnology and materials science to address challenges at the nexus of water and energy, such as developing low-cost water treatment technologies that improve global access to safe drinking water. He has published 50 peer-reviewed articles in leading journals, including PNAS, Energy & Environmental Science, and Nature Communications. His work has been cited over 5000 times with an H-index of 23. Dr. Xie is a recipient of the NSF CAREER award in 2019.

Read Xing Xie ’s Emerging Investigator Series article “Locally Enhanced Electric Field Treatment (LEEFT) with Nanowire Modified Electrodes for Water Disinfection in Pipes” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on Emerging investigator series: Locally Enhanced Electric Field Treatment (LEEFT) with Nanowire Modified Electrodes for Water Disinfection in Pipes. How has your research evolved from your first article to this most recent article?

The LEEFT technology for water disinfection was first demonstrated in the early 2010s at Stanford, although it was not given the name “LEEFT” until recently. As a Ph.D. student, I was involved in the development of the first-generation LEEFT devices. When I started my own lab at Georgia Tech in 2017, I believe the LEEFT technology can be transformative. Potentially, it will change our current water treatment strategies and infrastructure in many places at different scales. While, of course, before the practical application of this technology, there are still many challenges to be addressed. We are interested in all aspects of research on this technology. Currently, we mainly focus on mechanism study, electrode development, and system design. The work described in this most recent article is part of our effort on the system design of the LEEFT technology.

What aspect of your work are you most excited about at the moment?

I am excited about all the aspects of our work on the LEEFT technology.

In your opinion, what are the most important questions to be asked/answered in this field of research?

The existing LEEFT devices are like black boxes: Efficient microbial inactivation has been achieved when water flows through the device, but the detailed mechanism is not fully understood. Irreversible electroporation is believed to be the primary antimicrobial mechanism during the LEEFT. Electroporation is a physical process that should not result in any by-products. However, it is not clear whether irreversible electroporation can be the sole mechanism to achieve high inactivation efficiency. All the previous LEEFT experiments utilized electrodes that would release Ag or Cu ions. Even though the bulk Cu concentration in the effluent has been reduced to less than 5 µg/L, it is possible that such a small amount of Cu still contributes to the microbial inactivation. In addition, some other antimicrobial mechanisms may exist. Therefore, we are studying the mechanisms using a lab-on-a-chip LEEFT platform, which allows the in-situ observation of the microbes under a microscope during the LEEFT.

What do you find most challenging about your research?

One of the biggest challenges for the further development of the LEEFT technology is to obtain durable electrodes through a reliable and scalable fabrication method. When LEEFT devices can operate steadily for a long enough period, researchers around the world will be able to study the LEEFT from different aspects.

In which upcoming conferences or events may our readers meet you?

I plan to attend the Gordon Research Conference on Environmental Sciences: Water and the Sustainable Nanotechnology Organization (SNO) Conference in 2020.

How do you spend your spare time?

I would like to spend my spare time with my family and friends playing board games or traveling to national parks. I have been to more than half of the 61 national parks in the US.

Which profession would you choose if you were not a scientist?

Maybe a chef. I make nanomaterials for environmental applications. Cooking and material synthesis have so many similarities: you need to have the right ingredients, use the right hardware, follow the right procedure, and control the right condition in each step.  While I am not always successful in making the desired nanomaterials, I usually quite enjoy the dishes I cook.

Can you share one piece of career-related advice or wisdom with other early career scientists?

Work on something unique, so you will be a leader rather than a follower.

Dr. Matteo Minghetti is an Assistant Professor in the Department of Integrative Biology at Oklahoma State University (OSU).  Dr. Minghetti received his Ph.D. in Ecotoxicology from the University of Stirling, UK in 2009. His diverse postdoctoral work includes projects on the transcriptional regulation of lipid metabolism in Atlantic Salmon (University of Stirling), the use of primary gill cultures for environmental biomonitoring (Kings College London), and the mechanisms of toxicity of metal nanoparticles in intestinal fish cells (Eawag – The Swiss Federal Institute of Aquatic Science and Technology). Dr. Minghetti is a recipient of a Marie Curie Fellowship (2012) and a National Science Foundation award (2018). His research interests lie at the interface between disciplines integrating analytical chemistry, molecular biology and physiology. The Minghetti Lab at OSU focuses on understanding physiological processes such as essential trace element homeostasis and developing tools for environmental biomonitoring.

Read Matteo Minghetti’s Emerging Investigator Series article “Linking Chemical Transformations of Silver and Silver Nanoparticles in the Extracellular and Intracellular Environment to their Bio-reactivity” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on Linking Chemical Transformations of Silver and Silver Nanoparticles in the Extracellular and Intracellular Environment to their Bio-reactivity. How has your research evolved from your first article to this most recent article?

Mechanisms of cellular metal homeostasis and handling have been the main focus of my research so far. During my PhD, I discovered that fish, similarly to humans, take up and excrete copper using specific copper transport proteins (CBP 2008, 147(4):459-9; Aquat. Toxicol. 2010, 97(1):23-33). After my PhD, I began to consider the environmental factors that affect metal bioavailability such us metal complexation with ligands present in the extracellular medium and competition with other cations.  To examine these concepts, I began to use in vitro models of the gill and intestinal epithelium.   This research revealed that extracellular metal speciation is linked to metal bioavailability and toxicity, but also that intracellular accumulation is not always linked with bio-reactivity (i.e. metallothionein gene expression) (Nanotoxicology 2016, 10(10):1526-1534). It became clear to me, therefore, that establishing the link between extracellular and intracellular metal speciation was necessary to fully understand the environmental conditions that potentially lead to organismal metal bioavailability, bioreactivity and toxicity. Intracellular metal speciation detection requires the use of X-ray spectroscopy, a technique that has been used extensively in physics, chemistry and geology but its use in biology is relatively new. In order to access this technique, I started a collaboration with Professor Jeffrey Catalano (Washington University in St. Louis), a geochemist and expert in synchrotron-based X-ray spectroscopic methods. I believe that studies at the interface between disciplines lead to potentially transformative discoveries.

What aspect of your work are you most excited about at the moment?

I am particularly excited about my recent work with X-ray florescence microscopy, which I use to visualize intracellular endogenous elements in cells. After many years of indirectly measuring the effect of metals and nano-metals in cells through gene and protein expression, I have found it really fascinating to be able to actually visualize clusters of metal ions in the cell with my own eyes.

In your opinion, what are the most important questions to be asked/answered in this field of research?

Once a metal or metal nanoparticle enters a cell, its intracellular fate over time will determine cellular effects. For instance, a particle might remain unaltered and non-bioreactive in the cell or dissolve rapidly and induce a sharp biological response. While important discoveries have been made in the nanotoxicology field with regard to factors influencing nanoparticle uptake (e.g. particle size, coating and corona protein interactions, etc.), our understanding of the factors influencing intracellular fate and transformation of nanoparticles is still poorly understood.

What do you find most challenging about your research?

Although fish cell lines have proven to be a useful tool for toxicological studies, they lack the complexity of the “real” tissue. A new generation of in vitro models is necessary to mimic more closely the responses of the whole organism. Such new systems will need to include multiple cell types in a substrate that mimics the tissue microenvironment. The main challenge is that developing such new in vitro models requires a multi-disciplinary approach involving collaborations between biologists and engineers.

In which upcoming conferences or events may our readers meet you?

I will attend the SETAC North America meeting, which is in Toronto this year. I am excited to co-chair a session on Nanotoxicology at this meeting and I would welcome colleagues to participate in this session and discuss new discoveries in this exciting field.

How do you spend your spare time?

I love spending time outdoors. Since moving to the U.S., my family and I have fallen in love with the National Parks’ system and we try to visit as many as possible every year. I also enjoy cycling with my local cycling club. It is a great way to relax!

Which profession would you choose if you were not a scientist?

I love driving and visiting new and exciting places.  Joking with my wife, I always say I would have been a good ice road trucker!

Can you share one piece of career-related advice or wisdom with other early career scientists?

As I’ve mentioned, I firmly believe that new discoveries lie at the interface between disciplines. So, I would encourage early career scientists to collaborate with researchers from other fields of science. I have always found it very informative and useful to attend seminars and meetings outside of my discipline. Other than that, follow your personal interest and passion and try not to be too influenced by current trends.

Dr. Kyle Doudrick is an Assistant Professor in the Department of Civil & Environmental Engineering & Earth Sciences at the University of Notre Dame (UND). Dr. Doudrick received his Ph.D. (2013) at Arizona State University where he investigated the use of photocatalysts for treating nitrate, a ubiquitous drinking water contaminant. His research group at UND seeks to solve critical problems in environmental engineering using nanotechnology, with a focus on developing physical-chemical technologies for treating water contaminants and understanding the fate and transport of nanoparticles in streams. Dr. Doudrick is a recipient of the National Science Foundation CAREER award and a 2019 Fulbright Scholar. He also has a passion for improving environmental engineering education using virtual reality (VR), including the development of 360 immersive tours. You can view his VR drinking water treatment plant tour on YouTube with or without a headset (https://www.youtube.com/watch?v=zRFBVFBZ1jI).

Read Kyle Doudrick’s Emerging Investigator Series article “protein adsorption and transformation on catalytic and food-grade TiO2 nanoparticles in the presence of dissolved organic carbon” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on Protein Adsorption and Transformation on Catalytic and Food-Grade. How has your research evolved from your first article to this most recent article?

I first started working with food-grade titanium dioxide during my Ph.D., where we characterized the surface chemistry and its effect on cells (Environmental Science & Technology 48 (11), 6391-6400; Cell Biology and Toxicology 30 (3), 169-188; PloS One 11 (10), e0164712). What stood out broadly from these studies was the difference between the titanium dioxide in our food and pharmaceutical products compared to the “chemical” or “catalytic” grade titanium dioxide that is often used in toxicity and transport studies. The food-grade titanium dioxide is present day – we are all ingesting it – but there have been few studies on the adverse effects. This includes studies about the adsorption of proteins to nanoparticles, which we understand to be critical for determining bioactivity. So, naturally, the first question that came to my mind was: does the protein adsorption behavior differ when we use more realistic nanoparticles like the food-grade materials? The work we present here confirms that the protein formation is quite different for the two types. Further, we provide evidence that the protein adsorption behavior changes if the nanoparticle is first exposed to dissolved organic carbon (e.g., from a stream), and this behavior can be quite different depending on the nanoparticle. I think these findings have some broad implications that should make us question whether we are choosing the right nanoparticles/scenarios in our experiments.

What aspect of your work are you most excited about at the moment?

We currently have a project in which we are investigating the transport of nanoparticles in realistic streams. We have a unique site at the University of Notre Dame called the Linked Experimental Ecosystem Facility (ND-LEEF). It has four hydraulically identical streams lined with varying media types, and we are adding nanoparticles to study the transport behavior under different conditions. In collaboration with Prof. Diogo Bolster, we hope to use this data to create a model that will be able to predict the transport better than what is currently available. I think these types of studies are an important step to simplifying the complexity that comes with investigating nanoparticles in real systems. We have already observed some interesting results and the paper should be out soon!

In your opinion, what are the most important questions to be asked/answered in this field of research?

As I eluded to above, I think figuring out how nanoparticles behave in real systems will be a critical and challenging question to answer. The myriad combinations of nanoparticle physical-chemical properties and environmental condition/scenarios presents us with an almost insurmountable challenge of creating theoretical based predictions (e.g., linking surface charge to transport behavior). These approaches may be good for simplified lab experiments, but they don’t scale well to realistic systems. So, when nanoparticles enter the environment after being released from, e.g., a food, do they eventually just become like any other metal oxide/organic carbon coated with organic matter or adsorbed to minerals or do they behave differently?

What do you find most challenging about your research?

One of the biggest challenges in studying nanoparticles in complex, realistic environments is the analytics. If you are interested in something like silver, then you must deal with its dissolution and/or transformation, and if you are working with carbon nanotubes then you are fighting against the high carbonaceous background concentrations. Our studies are only as good as our detection methods, and I think this has become a critical area that is not getting enough attention, especially if we want to move beyond lab-scale experiments. These limitations force us to be creative with experimental design by selecting certain nanoparticles and using model field sites, but that makes it difficult to achieve truly realistic experiments (e.g., tracking nanoparticle movement in Lake Michigan or in a large river).

In which upcoming conferences or events may our readers meet you?

I will be at two upcoming conferences: the American Chemical Society in August and the Sustainable Nanotechnology Organization (SNO) in November, both in San Diego. I highly recommend the SNO conference to this audience as it is a great platform to discuss our research amongst nano-minded people.

How do you spend your spare time?

I have numerous hobbies, but these days I rarely get to partake. When I do find some free time, I enjoy spending it with my family and friends, traveling, playing volleyball, reading, hiking, gardening, photography, and playing musical instruments poorly.

Which profession would you choose if you were not a scientist?

A question many tenure track faculty seem to ask themselves around year five. I do love research and teaching, but I could see myself enjoying many other professions. Imaging what pathways you might have taken is fun and I’ve often thought I could have been a good tour guide or CIA analyst. But, I think most of all, I would like to have a sustainable farm somewhere with lush, rolling hills where I could write fantasy or science fiction stories when I’m not tending to my animals (and bees) and crops. Who knows, maybe one day I will retire and get to say I did both!

Can you share one piece of career-related advice or wisdom with other early career scientists?

How about one big congregated piece of advice? I think many young researchers stress about hitting the ground running so they can carve out their “niche” and work on the next big thing. Instead, I think when starting out you just should focus on a topic that you are passionate about and become good at that. Being a young researcher/professor is challenging and I think if you concentrate on becoming a better scientist/teacher, mentor, and writer, then the rest will fall into place as you gain more experience. And there are many books available that can help you along the way – Boice is a good place to start, and don’t feel guilty about taking some time out of research or writing to read it. Definitely make time for your family and friends and don’t get into a habit of working weekends (easier said than done). Don’t take bad reviews to heart, and in return be respectful and constructive when you write proposal and paper reviews. Most of all, have fun.