Melanoma, a type of cancer that develops in melanocytes, is usually caused by direct exposure of skin to ultraviolet (UV) radiation resulting in cellular damage. In this study, a procedure to determine the effects of various commercial sunscreens with SPF values ranging from 15 to 100 was developed using pig skin to mimic human skin. These…

Earth's field nuclear magnetic resonance (EFNMR) spectroscopy offers students a unique opportunity to consolidate their understanding of NMR spectroscopic theory through hands-on practice with a simple spectrometer. A comprehensive, 6 h experiment is presented for the introduction of low-field NMR techniques, covering spectroscopy, relaxivity, and…

Synthesis and characterization of nanomaterials yields opportunities for instruction of related topics in solution chemistry and materials science, as well as spectroscopy connecting to band theory, the "particle in a box" quantum mechanical model, and thermodynamics. In collaboration with an undergraduate research assistant, we have…

Process analytical technologies (PATs) are used in the pharmaceutical and other industries to monitor chemical processes in real-time with analytical instrumentation. Each PAT analyzer brings its own advantages and disadvantages to the process, and multiplexing PAT analyzers can be advantageous as they can provide confirmatory measurements and…

The use of methanol-water mixtures as solvents for sample preparations is common in many instrumental analytical procedures for compound quantification at trace concentration levels. The reliability of the analytical method depends upon several factors including consistency of instrumental setup and calibration, quality of standards used and…

Chromatography is a ubiquitous technique in analytical chemistry, and high-performance liquid chromatography (HPLC) is the industry standard for quantitation of components in solution mixtures. However, demonstrating the principles of liquid chromatography to undergraduates via HPLC-based experiments often proves ineffective because of the fully…

Student-built photometers are recognized as being useful tools in teaching laboratories that help students understand the concepts behind experimental measurements, and several devices have been reported that employ photoresistors as the detector of choice. We demonstrate here an improvement over these instruments and the analyses thereof,…

This laboratory experiment demonstrates the important utility of transition-metal complexes as catalysts in the addition reaction of carbon tetrabromide (CBr ) to select alkenes. This application offers students the opportunity to understand why transition-metal complexes are worth synthesizing. The experiment builds on fundamental theories…

This work describes the design, building, and testing of miniature, low-cost LED-LDR colorimeters for absorption-spectrophotometry experiments. It also describes using these colorimeters for simplified context-based-learning (CBL) activities in school teaching laboratories and for public-engagement events. The colorimeters are simple and robust,…

An operationally straightforward, project-like laboratory experiment has been developed in which students directly compare the reactivity of two heterocycles, a cyclic "O,O"-acetal (standard C-O protecting group) and a cyclic "N,O"-acetal (oxazolidine), toward sodium borohydride and methylmagnesium iodide. Students synthesize a…

This inquiry-based lesson gets students moving to simulate chemical reactions in a way that allows them to visualize, understand, and retain information about chemical reactions in the stratosphere. Students then look at scientific data and conduct research to understand trends in the data and the impact of chlorofluorocarbons (CFCs). These…

One dimensional (1-D)[superscript 1] H and [superscript 13]C NMR experiments are common tools used in undergraduate organic laboratories to characterize synthesized molecules. However, 1-D NMR spectra cannot always provide unambiguous structure determination. In research laboratories, advanced NMR spectroscopy methods are employed for structural…

Here, we developed an integrated course based on two dimensional-electrophoresis and spectrometry mass (2DE-MS) technique for undergraduate students to help them learn proteomic techniques. The soluble proteins in wild type and gene knockout bacteria were separated by 2DE and the differently expressed proteins were identified by MS analysis. The…

Plants encounter several different threats that affect their well-being during the spring. With chemistry, plants may defend themselves from, for example, excess UV-radiation and herbivores. The defense compounds between plant species vary, which makes it possible to utilize chemistry in identifying the plant species. In this laboratory…

Microplastic contamination of the environment is a major concern but detecting such contamination presents a challenge, particularly for particles <0.1 mm in size. Community scientists and students who participated in a plankton monitoring program and routinely examined samples of seawater using brightfield microscopy, often found fragments and…