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A required first-year laboratory course was overhauled into a semester-long biosciences course-based undergraduate research experience (BioCURE) with a goal of enhancing learning and improving retention. Student attributes and outcomes were continually monitored by the University's Institutional Research office over a 5-year period and compared against the pre-BioCURE (traditional Biology lab course). Success in the BioCURE was found to be correlated with a passing grade (ABC) in prerequisite majors' chemistry as opposed to nonmajors' chemistry; concurrent enrollment in either majors' or nonmajors' chemistry was less effective than prerequisite majors' chemistry. This unique metric, of assessing the value of a chemistry course as seen through the success in a subsequent bioscience course, provides the authors with convincing evidence to encourage educators to focus on a rigorous, early academic chemistry foundation as well as emphasize interconnections with other disciplines. Diving deeper, success in a more challenging chemistry course prior to taking a required biology course during biological science students' first two collegiate years correlated with increases in student success in biological sciences degree plans, as evidenced by subsequent increases in retention into the third year and six year graduation rates. Students with ABC grades in any first-year chemistry course had a higher rate of graduating in an initially chosen bioscience discipline, but majors' chemistry benefited at-risk students disproportionately more than high-GPA students showing that early chemistry success is critical for strengthening a diverse STEM workforce.

Carbohydrates are an essential group of molecules to the organic chemistry classroom providing molecular relevance to a common ingredient in chemical biology. While the meticulous elucidation of the carbohydrate structures by Fischer and others is an engaging topic in the lecture, there are few laboratory experiments that can emulate carbohydrate complexity. Advanced and multidimensional NMR (2D NMR) techniques such as correlation spectroscopies (COrrelation SpectroscopY (COSY), [superscript 13]C Distortionless Enhancement by Polarization Transfer (DEPT), and HETeronuclear CORrelation (HETCOR) or Heteronuclear Single Quantum Coherence (HSQC)) have become more routine as they require less time on today's instruments and are taught more often in lecture. A laboratory experiment is described for second-year introductory undergraduate organic chemistry students that involves the transformation of nutraceutical N-acetyl-d-glucosamine to a-chloroglucosamine tetraacetate. After synthesis and simple workup, students collect four different NMR spectra from which they identify each [superscript 1]H signal in the product. Students learn to identify each signal's multiplicity and how multiple NMR experiments are used to characterize a product. Student confidence in NMR characterization was assessed on a small subset through postlab questions and pre- and postsurvey data.

Additions to the popular evaporation rate determination laboratory of alcohol-based hand-rub sanitizers are described here. Significantly, inquiry-driven protocols for formulating hand-rub sanitizers, falling-ball viscometry, and sanitizer efficacy are included. Incorporation of familiar substances ("molecular relevance") enables students to assimilate knowledge and connect to and recognize interrelated disciplines. To stimulate engagement and project ownership, students were given the opportunity to alter sanitizer formulations by varying the amount and molecular weight of the gelling agent. Viscosities were determined using a falling-ball viscometer to integrate physics and fluid dynamics concepts into these experiments. Lastly, to stress microbiological applications and determine the efficacy of their hand sanitizers, students tested the formulated hand sanitizers for qualitative efficacy using agar plating of skin secretions and comparing colonies formed from sanitized versus nonsanitized hands. Chemistry students with diverse interests recognized links across disciplinary boundaries (e.g., increased their awareness of physical properties of hand sanitizers and the relationship of molecular-scale phenomena to these properties). This three-hour laboratory provides an interdisciplinary supplement directly designed for freshman chemistry and engineering chemistry undergraduates and increases integration among biology, chemistry, engineering, and physics.

Glyphosate (N-(phosphonomethyl)glycine) is the most widely used herbicide on earth. A simple assay to quantify glyphosate concentrations in environmental samples was developed as part of an interdisciplinary effort linking introductory laboratory courses in chemistry, biology, and microbiology. In this 3 h laboratory experiment, students used UV-vis spectroscopy to quantify glyphosate in prepared unknowns and supernatants from glyphosate-treated soil samples. Regression analysis indicated that the assay is linear up to 20.0 ppm, making it particularly useful for detection of low levels of glyphosate in environmental samples. The assay can be used to quantify the activity of glyphosate-degrading soil microorganisms by comparing glyphosate levels between autoclaved and nonautoclaved soil slurries.