Two groups of undergraduates have published work arising from a Winter 2025 CHM414 class taught by Dr. Soha Ahmadi, a postdoctoral fellow at the Department of Chemistry.
“Exploring DNA Nanostructures as Surface Engineering Techniques for Optimizing Nucleic Acid Biosensor Performance,” by Kepler Pyle, Naz Savranoğlu, Selin Naz Avdan and Soha Ahmadi, appeared in Electrochem 2025.
“Molecular Imprinting Polymer-Based Sensing of Neonicotinoids,” by Jelena Golijanin, Diane Hyewoo Lee, Riley Y. Li and Soha Ahmadi, was published in 2025 by Sensors.
Both publications arose from a new assignment developed by Ahmadi especially for the class.
The Course
Biosensors and Chemical Sensors (CHM414/ CHM1102) focuses on development, design, and operation of biosensors and chemical sensors. Students learn about the architecture of sensor systems and the different technologies behind them, including electrochemical, optical and acoustic wave techniques. A major emphasis is placed on surface chemistry, which plays a central role in how sensors interact with the molecules they are designed to detect.
“Sensors are an integral part of modern technology, ranging from simple devices that measure physical properties like temperature to complex systems incorporating human cells. They have a range of applications from everyday life to advanced technologies used in health monitoring, industrial processing, pharmaceutical analysis, automotive technology, military systems, and environmental monitoring,” explained Ahmadi.
“This course introduces students to chemical sensors and biosensors, specialized devices that detect chemical or biological species and convert that information into a measurable signal.”
Ahmadi took CHM414 herself as a PhD student. “Teaching it years later felt like coming full circle. I wanted students not just to learn about sensor technology, but to experience what it feels like to design a device that solves a real problem.”
“Designing a new assignment for this course felt very similar to designing a biosensor: you start with a challenge, identify the gap, and build something with purpose.”
With this in mind, Ahmadi developed new assignments that led to a capstone project intended to bridge scientific research with entrepreneurial thinking.
Undergraduate students worked in teams on a cascade of assignments that encouraged them to find a real-world problem or a research question that aligned with their interests and explore how sensor technology could be applied to solve the problem.
The resulting projects were exciting. “Overall, all students performed very well. Several undergraduate teams developed complex, well-justified sensor designs that directly addressed meaningful real-world challenges. Some went a step further by naming their sensors and even designing logos for potential startup ventures, reflecting a high level of creativity, initiative, and entrepreneurial thinking.”
“In addition to the overall high quality of assignments, there were many exceptional ideas with clear commercialization potential.”
Inspired by this outstanding work, Ahmadi immediately offered support to students interested in pursuing their designs beyond the classroom. “I encouraged them to consider submitting their work and offered to supervise and guide the revision process. Several undergraduate groups expressed interest in publishing their articles. I closely supervised two of these groups.”
Manuscripts for both projects were submitted at the end of September 2025. After undergoing major revisions recommended by reviewers, both articles were successfully published in November 2025.
The Publications
Pyle, Savranoğlu and Avdan teamed up to explain Exploring DNA Nanostructures as Surface Engineering Techniques for Optimizing Nucleic Acid Biosensor Performance. They told Chemistry Stories:
Many modern medical tests rely on biosensors—devices that can detect the presence of specific biological analytes. One of the more well-known examples of this technology is a glucose meter; an instrument used by diabetics to monitor their blood sugar. A chemical reaction between an enzyme-laden test strip and a sample of blood produces an electrical signal, which is then measured by an electrode.
This same concept is being used to help diagnose diseases in their early stages. Throughout the medical research community, there has been a push to identify compounds that are characteristic of specific ailments, otherwise known as biomarkers.
By recognizing the target molecule and converting that recognition into an electrical signal, it is possible to quickly and accurately diagnose a patient with a number of illnesses. Nucleic acids have emerged as an intriguing class of biomarkers, as diseases like cancers often generate characteristic tumour DNA sequences. However, one of the major obstacles to clinical implementation is ensuring the sensor can function at very low concentrations.
Our paper reviews the recent use of DNA-based structures designed to improve their performance: tetrahedral DNA nanostructures, DNA hydrogels, and self-assembled monolayers. Each of these three techniques is able to increase the ability of the sensor to detect the target nucleic acids while providing their own unique advantages. By harnessing their potential, researchers can pave the way for improved early disease detection, personalized medicine, and point-of-care testing.
When we presented this idea to Dr. Ahmadi, she noted that it had strong potential, motivating us to explore the idea more deeply and eventually develop it into a full review paper examining the chemical and technological strategies underlying our proposed system.
What ultimately convinced us to commit to the publication process was a combination of genuine curiosity, teamwork, and strong mentorship. Writing the paper allowed us to synthesize what we had learned in the course with current literature, and to contribute something meaningful to an active area of research. The consistent guidance and encouragement we received made the effort feel both achievable and worthwhile.
Dr. Ahmadi was the central pillar of our success throughout this project. From the earliest stages of ideation to the final revisions of the manuscript, her mentorship shaped both the direction and quality of our work.
As an instructor, she fostered an environment that encouraged curiosity and independent thinking, while also emphasizing scientific rigor. As an advisor, she helped us refine a broad set of ideas into a cohesive and focused paper, and guided us through multiple rounds of writing, revision, and clarification.
Having the opportunity to work closely with an expert in biosensors as undergraduates was invaluable. Her support not only strengthened the paper itself, but also gave us confidence to pursue research and publication at this stage of our academic careers.
This paper represents an important milestone, but not an end point. We are continuing to work on this project as a team, with ongoing advice from Dr. Ahmadi, and we see clear opportunities for the research to evolve further.
The strategies discussed in the paper open avenues for future experimental exploration and use of biosensors. The project has also shaped our research interests and how we think about translating fundamental chemistry into practical diagnostic technologies.
What ultimately convinced us to commit to the publication process was a combination of genuine curiosity, teamwork, and strong mentorship. --Kepler Pyle, Naz Savranoğlu, Selin Naz Avdan
Jelena Golijanin, Diane Hyewoo Lee, and Riley Y. Li wrote the following, meanwhile, about Molecular Imprinting Polymer-Based Sensing of Neonicotinoids
Our paper discusses recent developments and applications of sensors for a newer class of pesticides called neonicotinoids and aims to identify useful trends that could be considered by other scientists when designing future sensors. This is important to study and limit the environmental persistence of these pesticides, which could potentially have harmful effects on human health and ecosystems in large quantities. The focus of our paper is on sensors using the molecularly imprinted polymer (MIP) technique for immobilizing the pesticide molecules to allow for detection.
An MIP can be thought of as a mould with grooves shaped like pesticide molecules. It is useful because it can speed up and improve accuracy of field sensor measurements in real samples, such as fruit.
We found our assignment topic to be important in the contexts of pollution, climate change and health crises stemming from food regulation. Additionally, we found a gap in the literature in terms of broadly discussing MIP-based neonicotinoid sensing, although work in this field has been conducted for over ten years already.
We also had great teamwork throughout the semester for various other projects within the course, so working together to publish this article was a fitting way to demonstrate our learning and collaboration in a meaningful way.
Dr. Ahmadi's teaching helped to familiarize us with chemical sensing methods as a whole, which was helpful to identify the key conclusions of previous papers, understand the sensor designs and contextualize the sensor strengths and limitations, although we did not have sensor research experience. Also, her feedback and support throughout helped us successfully navigate the reviewing and publishing process for the first time.
We have all chosen very different directions following undergrad. Jelena is currently pursuing an M.Sc. in Organic Chemistry, while Riley is pursuing an M.A.Sc. in Chemical Engineering and Applied Chemistry and Diane is finishing her B.Sc. in Pharmaceutical Chemistry. For us, this is the end of this project for now.
However, the diverse skill sets we are working towards and our knowledge about MIP chemical sensor design may open opportunities for us to work together again in a similar field of research.
From publication to pitching Ahmadi continues to support further development of CHM414 projects for interested students. “Following the course, three undergraduate groups reached out to continue developing their biosensor concepts. I assisted these teams in preparing applications to one of the University of Toronto’s startup accelerators. I also supported one group in applying to a pitch competition. This group demonstrated strong enthusiasm for transforming academic work into entrepreneurial action.”
“The students proposed sensors to overcome a real-world challenge, developed pitches, and wrote review articles, some of which were published or turned into startup ideas. Their creativity and determination reminded me of why I love teaching.”