Although kinetics forms a foundational part of the chemical curriculum, laboratory experiences with the subject are often limited and lack relevance to the actual practice of chemistry. Presented is an inquiry-based lab focused on Michaelis− Menten kinetics, implemented in an upper-level, university physical chemistry laboratory. Student learning was assessed over the course of three years via a pre-and post-test scheme that evaluated student understanding of Michaelis−Menten concepts and experimental design. Results indicate improvement in both domains, in line with previous results in the inquiry-based laboratory literature.

It also serves as a foundational element of modern nanotechnology through its "bottom-up" approach toward fabrication at the nanoscale. These strategies are omnipresent in nature where the self-assembly of organic molecules underlies most biological processes. For example, amino acids are known to form chiral supramolecular assemblies on various substrates with intricate long-range ordering. [17][18][19][20] The study of amino acid self-assembly can thus enhance our understanding of fundamental biological processes, such as chiral selectivity and recognition. [21,22] In our ongoing efforts to explore the surface chemistry of amino acids on Cu(111), [23,24] we observe behavior that is absent from conventional molecular self-assembly. To date, all of the amino acids that we have investigated at intermediate surface coverages (30-70% of a monolayer (ML)) self-assemble into their own distinct molecular superstructures. However, even though each amino acid exhibits unique molecular ordering based on its associated molecular backbone, we have observed a shared, common property where they all disrupt and immobilize the diffusion of Cu adatoms on the underlying surface. The result of this immobilization is the formation of isolated Cu islands of distinct sizes and shapes that are dispersed across the surface and throughout the capping molecular superstructures.Surface diffusion and molecular self-assembly are two critically important processes in chemistry and nature. Amino acids deposited on a Cu(111) surface driving a separation at the 2D limit between self-assembling molecules and diffusing copper atoms is reported. Since the self-assembling amino acids prefer non-planar, tridentate bonding with neighboring adatoms, they attach to and immobilize diffusing copper adatoms on the surface. This chemical interaction freezes out the copper diffusion causing the condensation of "solid" copper adatom islands on the surface. Such separation and immobilization are observed for eight different amino acids, suggesting the generality of this phenomenon beyond a single amino acid species. Furthermore, at elevated temperatures, a disruption of the prototypical Ostwald ripening of adatom islands is also observed. These results provide fundamental insight into chiral molecular self-assembly and its interplay with metal atom surface diffusion.

With increasing interest into the origin of life as well as the advancement of medical research using nanostructured architectures, investigations into amino acid assemblies have increased heavily in the field of surface science. Amino acid self/assisted-assembly on metallic surfaces is typically investigated with Scanning Tunneling Microscopy at low temperatures and under ultra-high vacuum in order to maintain a pristine surface and to provide researchers the tools to atomically interrogate the surface. However, in doing so, results often tend to be uncertain when moving to more realistic conditions. The investigation presented focuses on the electrochemical STM study of five simple amino acids as well as two modifications of a single amino acid and the means by which they interact with Au(111). Using EC-STM under in situ conditions, the amino acids were shown to have a considerable interaction with the underlying surface. In all cases, the amino acids trapped diffusing adatoms to form islands. These findings have also been observed under UHV conditions, but this is the first demonstration of the correlation in situ. Results indicate that an increase in the molecular footprint of the amino acid had a subsequent increase in the area of the islands formed. Furthermore, by shifting from a nonpolar to polar side chain, island area also increased. By analyzing the results gathered via EC-STM, fundamental insight can be gained into not only the behavior of amino acids with the underlying surface, but also into the direct comparison of LT-UHV-STM data with imaging performed under ambient conditions.

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