Current Group Members | Peng Group Research Lab

Master student


Justin MacLeod justin.macleod@mail.utoronto.ca	Justin started his masters with the Peng group in September 2025. He is currently working on investigating the early events of toxicity of 6PPDQ within salmonids; to accomplish this he uses no-label chemical proteomics approaches such as PELSA and CETSA, as well as using Activity based protein profiling to hopefully uncover the protein target of 6PPDQ. In his spare time he loves playing video games, kickboxing and watching Survivor.

Justin MacLeod
justin.macleod@mail.utoronto.ca

Justin started his masters with the Peng group in September 2025. He is currently working on investigating the early events of toxicity of 6PPDQ within salmonids; to accomplish this he uses no-label chemical proteomics approaches such as PELSA and CETSA, as well as using Activity based protein profiling to hopefully uncover the protein target of 6PPDQ. In his spare time he loves playing video games, kickboxing and watching Survivor.


Hannah Byun hannah.byun@mail.utoronto.ca	Hannah is from Port Moody, BC, and obtained an HBSc degree in Environmental Chemistry and Biomedical Toxicology at U of T in 2025. In her undergraduate degree, she worked with Prof. Peng to characterize how 6PPD-Q alters the metabolic profile of a coho salmon embryonic cell line to identify its downstream effects. She then joined the Peng group as a Masters student in 2025 and is working with Dr. Samar Moussa from Environment Canada on characterizing the identity and toxicity of PPD transformation products formed from various atmospheric oxidants.

Hannah Byun
hannah.byun@mail.utoronto.ca

Hannah is from Port Moody, BC, and obtained an HBSc degree in Environmental Chemistry and Biomedical Toxicology at U of T in 2025. In her undergraduate degree, she worked with Prof. Peng to characterize how 6PPD-Q alters the metabolic profile of a coho salmon embryonic cell line to identify its downstream effects. She then joined the Peng group as a Masters student in 2025 and is working with Dr. Samar Moussa from Environment Canada on characterizing the identity and toxicity of PPD transformation products formed from various atmospheric oxidants.


Anna Kirkland anna.kirkland@mail.utoronto.ca	Anna received her Honours B.Sc. in Chemistry with a concentration in Chemical Toxicology at Carleton University in Spring 2024. During her undergraduate degree she gained analytical environmental chemistry experience through analyzing house dust samples for polycyclic aromatic hydrocarbons to inform risk assessment and her thesis which explored the capability of microbially induced corrosion to recover valuable metals from electronic waste. She joined the Abbatt and Peng groups for her Master’s in September 2024 to study the heterogeneous reactions of organic contaminants and the toxicity of their transformation products.

Anna Kirkland
anna.kirkland@mail.utoronto.ca

Anna received her Honours B.Sc. in Chemistry with a concentration in Chemical Toxicology at Carleton University in Spring 2024. During her undergraduate degree she gained analytical environmental chemistry experience through analyzing house dust samples for polycyclic aromatic hydrocarbons to inform risk assessment and her thesis which explored the capability of microbially induced corrosion to recover valuable metals from electronic waste. She joined the Abbatt and Peng groups for her Master’s in September 2024 to study the heterogeneous reactions of organic contaminants and the toxicity of their transformation products.


Tim Tao	tim.tao@mail.utoronto.ca

PhD Candidate


Wanzhen Chen wanzhen.chen@mail.utoronto.ca	Wanzhen completed her Hon. BSc. at the University of Toronto with a Chemistry Specialist and Earth & Environmental Science Major. She joined the Peng group in January 2020. She is currently a PhD candidate in the Civil and Mineral Engineering department at UofT, co-supervised by Professors Robert Andrews and Hui Peng. Her current project focuses on the non-targeted analysis of plastic additives and their chemical toxicities. Outside of the lab, her hobbies include playing board games and singing.

Wanzhen Chen
wanzhen.chen@mail.utoronto.ca

Wanzhen completed her Hon. BSc. at the University of Toronto with a Chemistry Specialist and Earth & Environmental Science Major. She joined the Peng group in January 2020. She is currently a PhD candidate in the Civil and Mineral Engineering department at UofT, co-supervised by Professors Robert Andrews and Hui Peng. Her current project focuses on the non-targeted analysis of plastic additives and their chemical toxicities. Outside of the lab, her hobbies include playing board games and singing.


Jolie Mille jolie.miller@mail.utoronto.ca	Jolie is from Bethesda, MD, and received her Honors B.Sc. degree in Chemistry from Carnegie Mellon University in May 2021. Jolie joined the Peng lab as a PhD student in September of 2021. She researches the biochemical mechanisms related to toxicity from organophosphate esters, which are commonly used as plastic additives and flame retardants. Outside of the lab, Jolie enjoys making pottery, reading, and snuggling with her cat.

Jolie Mille
jolie.miller@mail.utoronto.ca

Jolie is from Bethesda, MD, and received her Honors B.Sc. degree in Chemistry from Carnegie Mellon University in May 2021. Jolie joined the Peng lab as a PhD student in September of 2021. She researches the biochemical mechanisms related to toxicity from organophosphate esters, which are commonly used as plastic additives and flame retardants. Outside of the lab, Jolie enjoys making pottery, reading, and snuggling with her cat.


Diwen Yang diwen.yang@mail.utoronto.ca	Diwen Yang obtained her masters degree from the Peng lab at the University of Toronto in 2022. She is currently a Ph.D. candidate supervised by Prof. Hui Peng in the Department of Physical and Environmental Sciences. In the Peng lab, she is working on identifying endocrine disrupting chemicals binding to human nuclear receptors from environmental matrices. Outside of the lab, she likes to play badminton and rock climbing.

Diwen Yang
diwen.yang@mail.utoronto.ca

Diwen Yang obtained her masters degree from the Peng lab at the University of Toronto in 2022. She is currently a Ph.D. candidate supervised by Prof. Hui Peng in the Department of Physical and Environmental Sciences. In the Peng lab, she is working on identifying endocrine disrupting chemicals binding to human nuclear receptors from environmental matrices. Outside of the lab, she likes to play badminton and rock climbing.


Alexander Kasperkiewicz alex.kasperkiewicz@mail.utoronto.ca	Alex received his B.Sc. in Chemistry and his M.Sc. in Analytical Chemistry from the University of Waterloo in 2018 and 2020, respectively. His primary interests during his time in Prof. Janusz Pawliszyn's Research Group were the development of solid-phase microextraction couplings to mass spectrometry, with applications in drugs of abuse quantification in biofluids and pesticide screening in food and feed. After some time spent working in industry and government, Alex joined the University of Toronto's Chemical Engineering and Applied Chemistry Department in 2024, co-supervised by Prof. Hui Peng and Prof. Frank Wania. In the Wania and Peng labs, Alex is working on developing air sampling strategies for the identification, source apportionment, and database construction of environmental pollutants. In his spare time, Alex enjoys cycling, running, and diving into a sci-fi or a history of science read.

Alexander Kasperkiewicz
alex.kasperkiewicz@mail.utoronto.ca

Alex received his B.Sc. in Chemistry and his M.Sc. in Analytical Chemistry from the University of Waterloo in 2018 and 2020, respectively. His primary interests during his time in Prof. Janusz Pawliszyn's Research Group were the development of solid-phase microextraction couplings to mass spectrometry, with applications in drugs of abuse quantification in biofluids and pesticide screening in food and feed. After some time spent working in industry and government, Alex joined the University of Toronto's Chemical Engineering and Applied Chemistry Department in 2024, co-supervised by Prof. Hui Peng and Prof. Frank Wania. In the Wania and Peng labs, Alex is working on developing air sampling strategies for the identification, source apportionment, and database construction of environmental pollutants. In his spare time, Alex enjoys cycling, running, and diving into a sci-fi or a history of science read.

PhD Student


Xing (Jessie) Qian xing.qian@mail.utoronto.ca	Xing (Jessie) completed her Hon. BSc. at the University of Toronto with a Chemistry Specialist and an Environmental Chemistry Major. She joined the Peng group in Setember 2023 when she was still an undergraduate student. Her current project focuses on the non-targeted analysis of environmental xenobiotics that bind with human proteins. Outside of the lab, her hobbies include listening to music and making bullet journal.

Xing (Jessie) Qian
xing.qian@mail.utoronto.ca

Xing (Jessie) completed her Hon. BSc. at the University of Toronto with a Chemistry Specialist and an Environmental Chemistry Major. She joined the Peng group in Setember 2023 when she was still an undergraduate student. Her current project focuses on the non-targeted analysis of environmental xenobiotics that bind with human proteins. Outside of the lab, her hobbies include listening to music and making bullet journal.

Postdoc Fellow


Dr. Xiaoyun Wang, xyun.wang@utoronto.ca	Xiaoyun Wang is a postdoctoral researcher in the Department of Chemistry at the University of Toronto. She received her Ph.D. from the Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, under the supervision of Prof. Guibin Jiang and Prof. Qunfang Zhou. Her research seeks to understand how small molecules influence human health through their interactions with proteins. Her work focuses on developing high-throughput enantioselective affinity selection mass spectrometry (E-ASMS) platforms for screening protein–chemical interactions, including those involving drugs and environmental contaminants. She also establishes standardized experimental datasets to support machine learning models for predicting molecular behavior.

Dr. Xiaoyun Wang,
xyun.wang@utoronto.ca

Xiaoyun Wang is a postdoctoral researcher in the Department of Chemistry at the University of Toronto. She received her Ph.D. from the Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, under the supervision of Prof. Guibin Jiang and Prof. Qunfang Zhou. Her research seeks to understand how small molecules influence human health through their interactions with proteins. Her work focuses on developing high-throughput enantioselective affinity selection mass spectrometry (E-ASMS) platforms for screening protein–chemical interactions, including those involving drugs and environmental contaminants. She also establishes standardized experimental datasets to support machine learning models for predicting molecular behavior.


Dr. Zhipeng Cheng chengzhipeng@nankai.edu.cn	Zhipeng is from Anqing, Anhui, China, and obtained his PhD degree from Nankai University in June, 2021 under the supervision of Prof. Hongwen Sun. After that, he works as a postdoctoral fellow and research assistant at Nankai university for three years. He joined Hui’s group in November, 2024 as a PDF, and is currently working on establishing an Affinity Selection Mass Spectrometry (ASMS) platform, integrating with combinatorial synthesis, to generate large chemical-protein interaction datasets for AI-driven bioactive chemical discovery. In his spare time, Zhipeng enjoys playing basketball and hiking.

Dr. Zhipeng Cheng
chengzhipeng@nankai.edu.cn

Zhipeng is from Anqing, Anhui, China, and obtained his PhD degree from Nankai University in June, 2021 under the supervision of Prof. Hongwen Sun. After that, he works as a postdoctoral fellow and research assistant at Nankai university for three years. He joined Hui’s group in November, 2024 as a PDF, and is currently working on establishing an Affinity Selection Mass Spectrometry (ASMS) platform, integrating with combinatorial synthesis, to generate large chemical-protein interaction datasets for AI-driven bioactive chemical discovery. In his spare time, Zhipeng enjoys playing basketball and hiking.


Dr. Yongwei Guo yongwei.guo@utoronto.ca	Yongwei Guo joined the Peng Lab at the University of Toronto as a Postdoctoral Fellow in 2026. His current research focuses on hit optimization and molecular glue discovery by integrating Affinity Selection Mass Spectrometry (ASMS) with combinatorial synthesis. Before joining the Peng Lab, he received his Ph.D. from Sun Yat-sen University in 2024 and spent two years as a postdoctoral researcher at the University of California, Riverside. Outside the lab, he appreciates good chemistry wherever he finds it.

Dr. Yongwei Guo
yongwei.guo@utoronto.ca

Yongwei Guo joined the Peng Lab at the University of Toronto as a Postdoctoral Fellow in 2026. His current research focuses on hit optimization and molecular glue discovery by integrating Affinity Selection Mass Spectrometry (ASMS) with combinatorial synthesis. Before joining the Peng Lab, he received his Ph.D. from Sun Yat-sen University in 2024 and spent two years as a postdoctoral researcher at the University of California, Riverside. Outside the lab, he appreciates good chemistry wherever he finds it.


Dr. Chengkang Chen chengkang.chen@utoronto.ca	Chengkang obtained his B.Sc. and Ph.D. in Environmental Science from Peking University in 2017 and 2022, respectively. In 2023, he joined the Department of Physical and Environmental Sciences at the University of Toronto as a postdoctoral fellow under the supervision of Prof. Frank Wania. Since 2026, he has been with the Department of Chemistry, co-supervised by Prof. Hui Peng and Prof. Frank Wania. Chengkang’s research aims to develop and apply mathematical models to advance our understanding of the factors that govern toxic chemical behavior along the continuum from initial production to health effects in an efficient and mechanistic manner. Currently, he focuses on integrating machine learning models, non-targeted analysis, and exposure models to predict, screen, and assess physicochemical properties and exposure potential of hundreds of thousands of chemicals.

Dr. Chengkang Chen
chengkang.chen@utoronto.ca

Chengkang obtained his B.Sc. and Ph.D. in Environmental Science from Peking University in 2017 and 2022, respectively. In 2023, he joined the Department of Physical and Environmental Sciences at the University of Toronto as a postdoctoral fellow under the supervision of Prof. Frank Wania. Since 2026, he has been with the Department of Chemistry, co-supervised by Prof. Hui Peng and Prof. Frank Wania. Chengkang’s research aims to develop and apply mathematical models to advance our understanding of the factors that govern toxic chemical behavior along the continuum from initial production to health effects in an efficient and mechanistic manner. Currently, he focuses on integrating machine learning models, non-targeted analysis, and exposure models to predict, screen, and assess physicochemical properties and exposure potential of hundreds of thousands of chemicals.

Undergraduate Student


Lily Held lily.held@mail.utoronto.ca	My name is Lily, and I’m from Frankfurt, Germany. I’m a third year student studying Chemistry and Environmental Science, and am mainly interested in Analytical Environmental Chemistry! For my CHM395 research project I am working in collaboration with Natural Resources Canada to manage hydraulic flowback and produced wastewater by analyzing the wastewater composition and known standards with LC-HRMS. I am super excited to be working with Prof. Peng and Tao Yang to learn more about machine learning and how to use the information from my experiments to deduce info about unknown contaminants and the efficacy of sorbents used to purify the wastewater.

Lily Held
lily.held@mail.utoronto.ca

My name is Lily, and I’m from Frankfurt, Germany. I’m a third year student studying Chemistry and Environmental Science, and am mainly interested in Analytical Environmental Chemistry! For my CHM395 research project I am working in collaboration with Natural Resources Canada to manage hydraulic flowback and produced wastewater by analyzing the wastewater composition and known standards with LC-HRMS. I am super excited to be working with Prof. Peng and Tao Yang to learn more about machine learning and how to use the information from my experiments to deduce info about unknown contaminants and the efficacy of sorbents used to purify the wastewater.

Collaborating Scientist


Dr. Jianxian Sun sunsjx@gmail.com	Sunny is from Penglai, China. She got her PhD degree from Peking University in 2014 under Professor Jianying Hu’s supervision, and then she spent three years as a PDF at University of Saskatchewan. Now she is a PDF in Hui’s lab, focusing on the research of high throughput identification of small metabolites bound to targeted proteins by pull-down assay. In her spare time, Sunny would go leisure swimming (because she swims very slow), although her spare time is almost taken by her daughter Vivian.

Dr. Jianxian Sun
sunsjx@gmail.com

Sunny is from Penglai, China. She got her PhD degree from Peking University in 2014 under Professor Jianying Hu’s supervision, and then she spent three years as a PDF at University of Saskatchewan. Now she is a PDF in Hui’s lab, focusing on the research of high throughput identification of small metabolites bound to targeted proteins by pull-down assay. In her spare time, Sunny would go leisure swimming (because she swims very slow), although her spare time is almost taken by her daughter Vivian.

Visiting Student


Tao Yang aot.yang@utoronto.ca	Tao Yang is a visiting Ph.D. student from Guangzhou Institute of Geochemistry, Chinese Academy of Science. Tao is interested in non-target screening of pollutants affecting fungal communities in Ontario watersheds. Outside of the lab, he enjoys hiking, working out, and playing eSports.


Shihao Wang uotshihao.wang@mail.utoronto.ca	Shihao is currently pursuing his Ph.D. at the Hong Kong Polytechnic University. In April 2026, he joined the Peng group at the University of Toronto as a visiting student. His work at U of T focuses on screening toxic chemicals in human products using chemical proteomics and non-target analysis techniques. Outside of research, his hobbies include playing badminton and basketball, as well as hiking.

Shihao Wang
uotshihao.wang@mail.utoronto.ca

Shihao is currently pursuing his Ph.D. at the Hong Kong Polytechnic University. In April 2026, he joined the Peng group at the University of Toronto as a visiting student. His work at U of T focuses on screening toxic chemicals in human products using chemical proteomics and non-target analysis techniques. Outside of research, his hobbies include playing badminton and basketball, as well as hiking.


Iris del Val García idelval@unizar.es	Iris did a Biotechnology degree at the University of Zaragoza and a Master in Biochemistry, Molecular Biology and Biomedicine at the Universidad Complutense de Madrid. She is doing her PhD at the University of Zaragoza, where her work focuses on the study of orphan G protein-coupled receptors, and is currently a visiting student at the University of Toronto.


Sophie Buller bullers@mcmaster.ca	Sophie is currently completing her Honours B.Sc. at Mcmaster University in the Integrated Science program with a Chemistry specialization. She is a visiting Undergrad in the Peng lab and joined in the spring of 2026.