Enhancing STEM Education by Integrating Research and Teaching in Photochemistry: An Undergraduate Chemistry Laboratory in Spectroscopy and Photochemistry

Enhancing STEM Education by Integrating Research and Teaching in Photochemistry: An Undergraduate Chemistry Laboratory in Spectroscopy and Photochemistry

Blog Article

Molecular spectroscopy and photochemistry constitute an integral field in modern chemistry.However, undergraduate level classes provide limited opportunities for hands-on experimentation of photochemistry and photophysics.For this reason, a simple laboratory experiment was designed that may be easily implemented into undergraduate teaching laboratories with the aim of introducing undergraduate students to UV/visible spectroscopy and photochemistry/photophysics and its possible applications.Samples of three unknown sunscreen formulations are given to students and they are asked to use a set of techniques to identify their molecular composition and to test their efficacy using basic laboratory equipment available to them.

In particular, 70 x 70 tablecloth the students are asked to complete the following tasks: (i) armada tantrum skis sample preparation using solvent extraction to extract active ingredients from the sunscreen lotion, (ii) identify the extracted molecular sunscreen constituents by Thin Layer Chromatography (TLC) and UV/visible spectroscopy, and finally (iii) study their photostability by means of steady state irradiation coupled with UV/visible spectroscopy.The students were provided with the following tools for data collection: silica-backed TLC plates, a short-wave lamp (254 nm, for TLC analysis), a UV-Vis spectrophotometer with an associated computer and software, and an LED lamp (315 nm) to irradiate the samples.Combined TLC and UV-Vis spectroscopy allowed the students to identify the extracted ingredients.UV irradiation confirmed the photostability of sunscreens.