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kueyoung kim

Undergrads in the lab: Kueyoung Kim (Zarzar Group)

25 March 2024
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Kueyoung Kim. Credit: Sarah Rehmeyer (3rd year chemistry major, minor in photography)

In this Q&A style interview, third-year chemistry major Kueyoung Kim discusses his undergraduate experiences such as working in a lab and being a co-first author on his first research publication with the Zarzar group.  


Q. What made you decide to pursue a chemistry degree at Penn State? Did anything about our undergraduate chemistry program stand out to you most? 

A. Because I had an older sibling who graduated from Penn State with a degree in chemistry, I knew it was going to be an excellent fit for me as well. I was especially drawn to the rigorous coursework, excellent research opportunities, and tight-knit community in the chemistry program here. Compared to other programs that I've seen, the smaller size of the chemistry major at Penn State allows everyone to know each other many of my closest friends are other chemistry majors I met in our first-year seminar or in class.   


Q. Not all undergraduates know that hands-on opportunities of working in research labs are available to them. When did you know you wanted to do research as an undergrad and what areas of chemistry interested you most?  

A. My interest in scientific research began in high school where I worked on an independent project synthesizing polymers from biological feed materials, such as apples or algae. Coming to Penn State, I knew I wanted to try my hand at research in a real academic lab and was especially interested in materials chemistry, which is how I ultimately ended up joining the Zarzar Lab.  

I received a lot of great support and advice from the Millennium Scholars Program which advocates for its scholars to join labs early. I remember discussing what type of research I felt most passionate about and whether I saw myself doing theoretical or experimental work with my advisors in the program. This was helpful in narrowing down potential research mentors.  


Q. How long have you been doing research in the Zarzar Lab? What was it about this research team that most intrigued you?  

A. I joined the Zarzar Lab as soon as I arrived at Penn State in 2021 and have been doing research with the group ever since. Not knowing a lot about chemistry or emulsions, I was most intrigued by videos on the group website showing active droplets chasing one another like predators and prey and dynamically organizing into clusters. Never having seen anything like it, I knew I wanted to dig deeper into the science behind why these "dead" droplets behaved as if they were alive.  


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Kim checking the imaging setup of the side view microscope. Credit: Sarah Rehmeyer


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A side view image of an oil droplet in surfactant (soap) solution taken with the custom built side view microscope. This is what the raw data collection for Kim's paper looked like – many videos which were then processed to get quantitative data. Credit: Sarah Rehmeyer


Q. At the end of the Fall 2023 semester, you were a co-first author in a paper published in JCIS (Journal of Colloid and Interface Science) titled "Liquid-liquid surfactant partitioning drives dewetting of oil from hydrophobic surfaces". It's not very often that undergraduate researchers get to co-author publications with a principal investigator (PI) and graduate student. Was this a project you got involved in from the start?

A. I joined this project from the very beginning where it looked very different from what ended up being published. I feel fortunate to have had the experience of identifying a research question to pursue and getting the chance to shape the story of our project from the very start.  


Q. What was it like working on a paper with a renowned chemist and decorated researcher like Dr. Lauren Zarzar?  

A. I learn new things every time I discuss my research with Dr. Zarzar and love seeing how she approaches problems and experimental design. Receiving the guidance of an expert while thinking through challenges and writing the story of our science inspires me to continue developing as a scientist.  


Q. Did you receive any helpful advice from the graduate students you worked with? 

A. Asking questions is a skill that needs to be practiced. I had never considered that asking good meaningful questions was something I could get better at. It is something that I pay more attention to now. 


Q. Tell us about your research in the paper "Liquid-liquid surfactant partitioning drives dewetting of oil from hydrophobic surfaces". What is the need-to-know? 

A. When you wash grease off your dishes using soap and water, you might not think much about what is happening at the molecular scale. However, this seemingly simple system of oil, soap, water, and a solid surface is surprisingly complex with a lot of different factors impacting how well the oil clings to the surface. We find that soapy water can cause oil to either spontaneously remove itself from the surface or adhere more tightly depending on the nature of the surface. While delving deeper into the underlying mechanism, we found that a balance of various molecular transport processes determines how the oil behaves over time. Given the frequency with which we encounter oil wetted on solid surfaces in cosmetics, paints, and other industries, we hope that this work can provide more fundamental understanding to inform the design of new products.   


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Fabrication of an oil-in-water emulsion in a vial. It’s as easy as adding some oil into surfactant solution and shaking to emulsify! This method was used to create all the droplets studied in Kim's paper. Credit: Sarah Rehmeyer


Q. Research publications tend to be extremely technical and academic, requiring a need to understand difficult chemical concepts and how the research should be structured for the intended audience to follow. How involved were you in the research and writing processes? Did you have a lot of prior writing experience that assisted you?  

A. I got the opportunity to be heavily involved at every step of the research and writing processes, from identifying a research question and designing experiments to drafting the manuscript and communicating with reviewers. Although I always enjoyed writing for my English classes in high school, I found that scientific writing was a different challenge as I worked to clearly communicate information in a compelling and efficient manner.  


Q. What did you find most difficult and or surprising while documenting and laying out your research? What exciting moments during your research can you recall? 

A. Since this project lies at the intersection of different fields and is fundamental in its motivation, I spent a lot of time thinking about how to best introduce and contextualize my research. Figuring out how to connect my work to both the scientific literature and applications that people care about was challenging yet satisfying as it made me gain more perspective on how my science fit into the broader picture.  

One exciting moment during our research occurred right as we started thinking about writing the first draft of our paper. While looking at some experimental results for a figure, we noticed that our data didn't quite align with what we had originally hypothesized. This realization was a turning point in our project as we developed a new hypothesis and modified the story of our paper.   

What I enjoyed most during the research and publishing processes was reading the literature from a broad range of fields and thinking about how the work of other scientists could inform my own project. At several points in this project, we were able to pose new hypotheses and understand more about our system solely from reading the literature, which I thought was incredibly exciting. 


Q. You worked with various instrumentation and digital methods for processing data in this project. Can you explain how they assisted your research?  

A. The instruments and data analysis methods were vital for our work as it enabled us to confirm our hypotheses and understand more about what was happening at the molecular scale. I especially appreciated how using only a couple different instrumentswe were able to conduct a wide range of experiments by playing with experimental design.  Our lab's custom built side view microscope in particular was critical for our paper since we were interested in analyzing how droplets wetted to solid surfaces over time. Using this microscope, we could precisely quantify how “favorably” a droplet wets (i.e. adheres) to a solid surface.

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Zarzar Lab custom built side view microscope used to image the side profile of droplets. Credit: Sarah Rehmeyer


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Q. You mentioned that the topic of your paper is in its early stages of discussion (i.e. there is not a lot of pre-existing research done on the subject). Why do you think this is when oil-in-water emulsion is a common everyday occurrence?  

A. This paper lies at the intersection of two active research areas: wetted droplets and oil-in-water emulsions. I think thatdue to our group's interdisciplinary focuswe were able to provide a new perspective to both fields which hadn't been considered by many.   


Q. How do you hope to see this research applied in the future?  

A. The widespread nature of oil-in-water emulsions in cleaning applications, cosmetics, paints, and pharmaceuticals (to name a few examples) makes me hopeful that this work will help inform smarter design of these products. In a bit of a different vein, I'm also excited about how this work could potentially be applied to understanding more about cell biology as there has been a recent explosion of interest in this kind of wetting behavior in cells.  


Q. Now that your first project is published, what new projects are you currently working on with the Zarzar group? 

A. I'm currently working on developing a new method to characterize how oil-in-water emulsions evolve over time. It's actually quite challenging at the moment to determine the microenvironments inside an emulsion due to its heterogeneity and dynamic nature. We envision that this new method will be widely used to enable more precise design of emulsions with desired properties.  


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A custom-built microscope in the Zarzar lab that can capture angularly resolved spectral information of a sample. Information about how different parts of a sample interacts with light can be extracted precisely. Kim has begun using this instrument to collect data for his next project. Credit: Sarah Rehmeyer


Q. What would you say to incoming chemistry students about the importance of undergraduate research and publishing? 

A. My time in the lab is when I do the most learning and growing as a scientist. Research provides a space where I can contextualize what I'm learning in the classroom while exploring topics that are not part of the undergraduate curriculum. At the same time, research has also taught me a lot of life skills and lessons such as persistence, collaboration, and communication which will be useful for the rest of my career.  

Publishing your research can also be daunting at first, but breaking the process into achievable chunks makes it a lot less scary. Although everyone's approach to publishing will look different, we started by thinking about the figures in our paper and how each figure captured the story we wanted to tell. 


Q: Outside of research, have you been involved in any other extracurriculars at Penn State? 

A. Within the chemistry department, I serve as an undergraduate research ambassador where I meet with current students who are interested in starting research. At Penn State, I'm currently the Vice President of Science Lionpride (the ambassador organization for the Eberly College of Science) and volunteer as an event supervisor for the Penn State Science Olympiad. I also independently organize science outreach events for the local school district and have been a state-wide event supervisor for Pennsylvania Science Olympiad.  


Q. Lastly, do you have any favorite Penn State traditions or memories that really stand out to you?  

A. Some of my favorite Penn State experiences have been at different social events organized by the Department of Chemistry, whether that be the pancake breakfast during finals week every semester or different holiday celebrations with the chemistry community. More broadly, I always enjoy taking part in THON as a part of Science Lionpride. It's amazing how the whole Penn State community comes together for 46 hours to fight against pediatric cancer, and it's always a privilege to be involved!  


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A fluorescent oil sample for Kim's next project. Fluorescence microscopy is being applied to droplets to derive information about how these droplets evolve over time. Credit: Sarah Rehmeyer


Media Contacts
Kathryn Harlow
Chemistry Communications Coordinator