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The Making Introductory Courses Real while Online (MICRO) laboratory project was developed to meet the need for hands-on experiments, focused on topics in analytical chemistry, to be delivered safely remotely or in a socially distanced in-person lab. Unlike more traditional lab experiments, MICRO laboratories use only microgram or nanogram amounts of chemicals; paper microfluidic technology is used to store and mix reactants. Instructional materials use an inquiry-based approach and are situated in a context that highlights the human impacts of the scientific analysis. To support broader-scale implementation of the experiments and promote a shift to more inquiry-based laboratory instruction, an array of supports were developed, including adaptable instructional materials, instructional videos for lab preparation, resource guides, and an introductory workshop. A cohort of nine institutions implemented MICRO laboratories both remotely and in person during Fall 2020. Students were able to successfully complete the experiments, and the inquiry nature of the laboratories led to an increased comfort with the trial-and-error nature of authentic scientific practice. Additionally, most faculty participants indicated a commitment to an increased degree of inquiry in their laboratory pedagogy.

A novel approach to building a membrane-based disposable well-plate, here applied to cyanide detection, is described. Chitosan encapsulated CdTe quantum dots with a maximum emission at 520 nm (CS-QD520) were used as fluorophores. The CS-QD520 nanoparticle was specifically quenched by copper(II), and the quenched CS-QD520 (Cu-CS-QD520) was deposited onto a glass microfiber filter (GF/B). Subsequent introduction of cyanide ion resulted in fluorescence recovery. The “signal-ON” fluorescence linearly correlated to cyanide concentrations in the range of 38.7 to 200 uM with a limit of detection of 11.6 uM. The assay was incorporated into a membrane-based well-plate format to enhance sample throughput. A three-layer paper/glass microfiber well plate design was cut using a laser cutter and assembled using a polycaprolactone (PCL) as a bonding agent in a low-cost laminator. The experimental conditions were optimized and applied to detect cyanide in drinking water with rapid, high-throughput, low-cost analysis.