Over the past several decades, green chemistry has gained prominence in chemistry education. However, the development of green chemistry curricula has not reached all levels of education equally, focusing mainly on elective and upper division courses. We deliberately focused our green chemistry curriculum redesign on a high enrollment introductory general chemistry laboratory course at the University of California, Berkeley. We developed over 30 new experiments that introduced students to green chemistry concepts and applications, while maintaining canonical general chemistry learning goals. The context of the curriculum and required course assignments encouraged students to use green chemistry principles to explore and solve real-world problems. After completing this redesigned course, we hypothesized that students would value green chemistry and feel more confident in their green chemistry knowledge. We developed new methods to measure students’ attitudes toward and understanding of green chemistry as a system instead of isolated reactions or processes. These assessments allowed us to better understand both the progression and limitations in student green chemistry and systems-thinking. Since over 2000 students complete the laboratory course each year, we used a combination of fixed response items and free response items from online surveys and in-class assignments and exams. This approach allowed efficient assessment of thousands of students, while still gaining valuable and nuanced views of student understanding and attitudes. These assessments indicated that the new general chemistry laboratory curriculum succeeded in providing an environment in which students learned green chemistry concepts and realized that chemistry has connections to their future courses and professions.

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In this undergraduate analytical chemistry experiment, students quantitatively assess the antibacterial activity of essential oils found in thyme leaves (Thymus vulgaris) in an authentic, research-like environment. This multiweek experiment aims to instill green chemistry principles as intrinsic to chemical problem solving. Students progress through various techniques including extraction, chromatography (TLC and HPLC), culturing bacteria, and disk diffusion via a process of guided exploration that emphasizes green experimental design. Approximately 600 undergraduate students carried out the experiment and self-reported substantial learning gains.

Several principles of green chemistry are introduced through this experiment designed for use in the undergraduate analytical chemistry laboratory. An established experiment of liquid CO2 extraction of d-limonene has been adapted to include a quantitative analysis by gas chromatography. This facilitates drop-in incorporation of an exciting experiment into an existing curriculum. The experiment provides an introduction to natural product extraction, calibration curves, and internal standards while simultaneously demonstrating alternative solvent selection for pollution prevention and increased chemical safety.

The detection of abnormal DNA base pairing arrangements and conformations is chemically probed in synthetic 32P-end-labeled deoxyribonucleotide oligomers using N-methyl-N-nitrosourea (MNU) and 2,12,-dimethyl-3,7,11,17-tetraazabicyclo-[11.3.1]heptadeca-1 -[17],2,11,13,15 pentaene-Ni (II) (Ni-complex) with KHSO5. The DNA targets studied are single-stranded (s-s) DNA, double-stranded (d-s) DNA, d-s DNA with G-G, G-A and G-T mismatches, d-s DNA with a single bulged G and d-s DNA with two bulged G's. The effect of the non-Watson--Crick structures on the formation of N7-methylguanine (N7-MeG) by MNU and the oxidation of G by Ni-complex is reported along with the Tm's and circular dichroism spectra of the different duplex oligomers. The results for MNU and Ni-complex show that the qualitative and quantitative character of the cleavage patterns at a G3 run change with the nature of the abnormal base pairing motif. Based on the DNA substrates studied, the results indicate that a combination of reagents which report electronic and steric perturbations can be a useful approach to monitor DNA mismatches and bulges.