Learning the theory and operation of instrumentation is an important part of the Quantitative Analysis Laboratory. After going remote in Spring 2020 the author desired to give students the experience of operating an HPLC: optimizing a method, generating calibration curves, and quantifying an unknown. The author normally implements the "Analysis of Analgesics by High Performance Liquid Chromatography" where students quantify the components of Excedrin using an old HP 1050 HPLC system with UV detection. A Python Jupyter Notebook was written to simulate the experience of operating the HPLC and hosted on the Chem Compute website (chemcompute.org), a website dedicated to providing access to computational chemistry for undergraduates. The notebook contained code to model the reversed-phase separation of aspirin, acetaminophen, and caffeine in a methanol/water mobile phase. The students entered their method (mobile phase composition, flow rate, and run time) into the notebook and output (absorbance vs time and peak integral tables) would appear on the screen. The strength of the simulation is that a visualization of the bands inside the column can be generated. Students can then see the compounds separating in the column. Surprisingly, students enjoyed changing the method parameters and optimizing the simulation. Half of the students reported that after using the simulation they now wanted to learn how to program Python or use computers in chemistry. All of the students reported that the visualization helped them to understand how compounds are separated in an HPLC. Students had difficulty converting from concentrations found from their calibration curve (μg/mL) to actual mass of the components in a tablet (mg). This was attributed to the virtual nature of the experiment where students couldn't prepare the samples.

Simulating an HPLC using a Jupyter notebook on the chem compute website

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.