Resveratrol Photoisomerization: An Integrative Guided-Inquiry Experiment

A kinetic study of trans–cis resveratrol photoisomerization was developed as a model guided-inquiry experiment for third-year undergraduate students to bridge the gap between explicitly prescribed laboratories and independent fourth-year research projects. Resveratrol photoisomerization was performed directly in a NMR tube within a UV photochemical reactor during which aliquots of sample were removed and diluted at specific time intervals for UV absorbance and HPLC measurements, whereas NMR spectra were performed directly in the original sample. Students in small groups are directly involved in the planning and organization of the experiment along with subsequent data analysis to statistically compare the apparent rate constant and half-life. Students appreciate the advantages and limitations of each technique with respect to quantitative and qualitative analyses, as well as understanding the photochemical properties of a recently discovered natural phytochemical with important biological properties relevant to human health. Students are also provided the opportunity to repeat the experiment to improve their technique and assess the reliability of their results. Our main objective was to promote inquiry-based learning in students within a defined experimental setting that integrates several fundamental concepts and instrumental techniques as a way to better prepare students for independent research in chemical biology.