Brennan Graves
Author: Brennan Graves | Major: Biochemistry, Biology | Semester: Fall 2024
Over the course of the Fall 2024 term, I worked alongside my mentor, Dr. Striegler, exploring the esterification of citric acid with ethanol under varying conditions. The overarching goal for this research was to refine citric acid ester synthesis methods and investigate the role of the resulting mono ester in Fe(III) citrate complexes. By focusing on synthesizing a mono ester derivative of citric acid, the deepening our understanding of how Fe(III) ions bind in both biological and environmental systems was sought. My role involved optimizing reaction parameters such as temperature, reaction time, solvent use, and pH adjustments to achieve higher yields and purities of these esters.
Like many chemistry projects, there were learning curves. A few days into my research, I encountered an unexpected equipment issues that caused one of my mixtures, for four hours instead of the planned two. This change in procedure yielded intriguing results in subsequent analyses, prompting me to conduct new, carefully controlled experiment to compare outcomes. Through open communication with my mentor and consistent documentation, I learned how important adaptability is in scientific work.
To carry out the experiments, I used reagents such as citric acid and ethanol , maintaining different molar ratios such as 3:1 or 1.5:1 of ethanol to citric acid. After heating these mixtures at 80–90 °C for up to 24 hours, I conducted extractions using ethyl acetate and deionized water. Subsequent rotary evaporation and phase separations helped isolate the organic layers, which I then analyzed via HPLC. This systematic approach revealed how small tweaks—like adjusting pH with potassium hydroxide or adding extra water—can drastically shift the distribution of ester products.
Aside from the technical side, I discovered that research rarely follows a straight path. I sometimes ended up with unexpected crystal formations or persistent emulsions that required creative troubleshooting. Thankfully, I received help from other students and Dr. Striegler who taught me tips on handling the rotary evaporator, managing sodium sulfate additions for drying, and reading HPLC data. My mentor guided me in prioritizing experiments, ensuring I used time efficiently while still exploring crucial variables.
Though I did not travel off-campus for archives or conferences, my campus lab experience provided ample opportunities to master sophisticated equipment and collaborate with peers. Analyzing multiple batches taught me the patience and diligence needed in iterative research. I was particularly excited to observe the interplay between traditional organic chemistry protocols and iterative experimental refinements, which highlighted the importance of optimizing reaction conditions to achieve high-purity products.
Preliminary data indicate that certain reaction conditions yield promising citric acid esters with the potential to be scaled up for useful laboratory amounts. I plan to refine the purification steps, possibly tweaking the exact time and exact molar ration which was used.
This research project has been an invaluable experience, helping me realize my passion for problem-solving and advancing chemical synthesis techniques. I’m thrilled to see that these initial efforts contribute to future studies to build upon and further refine chemical synthesis methodologies to expand our understanding and application of esterification processes.