Teaching materials characterization to support student research projects requires a systematic educational approach, because characterization involves a combination of analysis instruments. As analytical instruments are expensive, it is difficult to provide multiple sets simultaneously. An effective educational program allows students to select their own research materials to characterize and apply their personal strategies of instrumental analysis. These strategies are designed around the purposes of the analytical instruments, e.g., molecular structure analysis, crystal structure analysis, morphology assessment, surface analysis, elemental analysis, and thermal analysis. An open-ended laboratory complements this educational purpose. Here, we report on an open-ended laboratory program for fourth-year undergraduate and graduate students at the Materials Characterization Central Laboratory at Waseda University (Tokyo, Japan). The goals of our open-ended laboratory program are to enable students to (1) conduct instrumental analysis, (2) operate analytical instruments, and (3) interpret their data. A team led by a supervisor and laboratory staff offers students a flexible program. This flexibility can be applied to various research fields, such as macromolecular chemistry, inorganic chemistry, organic chemistry, physical chemistry, electrochemistry, physics, catalyst chemistry, biomaterials science, and chemical engineering. These diverse research fields demonstrate the feasibility of applying our open-ended laboratory program to student research projects.

Zerumbone is a sesquiterpene present in Zinger zerumbet. Many studies have demonstrated its marked anti-inflammatory and anti-carcinogenesis activities. Recently, we showed that zerumbone binds to numerous proteins with scant selectivity and induces the expression of heat shock proteins (HSPs) in hepatocytes. To dampen proteo-toxic stress, organisms have a stress-responsive molecular machinery, known as heat shock response. Heat shock factor 1 (HSF1) plays a key role in this protein quality control system by promoting activation of HSPs. In this study, we investigated whether zerumbone-induced HSF1 activation contributes to its anti-inflammatory functions in stimulated macrophages. Our findings showed that zerumbone increased cellular protein aggregates and promoted nuclear translocation of HSF1 for HSP expression. Interestingly, HSF1 down-regulation attenuated the suppressive effects of zerumbone on mRNA and protein expressions of pro-inflammatory genes, including inducible nitric oxide synthase and interlukin-1β. These results suggest that proteo-stress induced by zerumbone activates HSF1 for exhibiting its anti-inflammatory functions.

We aimed to achieve wide area rapid monitoring of the crystallinity change in poly(lactic acid) (PLA) during photodegradation caused by ultraviolet (UV) light by using a newly developed near-infrared (NIR) camera (Compovison). Several kinds of PLA samples with different crystallinities and their blends with poly[(3)-(R)-hydroxybutyrate] were prepared. Their two-dimensional NIR spectra in the 1,000-2,350-nm region were measured by Compovision at a 5-min interval during photolysis. An intensity decrease of the band in the 1,900-1,925-nm region due to the second overtone of the C = O stretching vibration of PLA was observed during photolysis. This suggests that an anhydride carbonyl is produced during photolysis. The NIR image of the crystallinity change monitored by the band at 1,917 nm in the standard normal variate spectra clearly shows the inhomogeneity of crystal evolution. A logarithmic increase was observed for all identified areas in the PLA film; however, the time to reach the maximum crystallinity was slightly different according to the initial crystallinity of the sample. It is likely that the initial crystallinity of the sample influences the degradation speed more than the degradation amount. These imaging results have provided fundamental chemical insights into the photolytic process for PLA, and at the same time they have demonstrated that the two-dimensional spectral data obtained by Compovision are useful for process monitoring of polymers.

In this study, direct analysis in real time adduct selectivities of a 558 in-house high-resolution mass spectrometry sample library was evaluated. The protonated molecular ion ([M + H]) was detected in 462 samples. The ammonium adduct ion ([M + NH]) was also detected in 262 samples. [M + H] and [M + NH] molecular ions were observed simultaneously in 166 samples. These adduct selectivities were related to the elemental compositions of the sample compounds. [M + NH] selectivity correlated with the number of oxygen atom(s), whereas [M + H] selectivity correlated with the number of nitrogen atom(s) in the elemental compositions. For compounds including a nitrogen atom and an oxygen atom [M + H] was detected; [M + NH] was detected for compounds including an oxygen atom only. Density functional theory calculations were performed for selected library samples and model compounds. Energy differences were observed between compounds detected as [M + H] and [M + NH], and between compounds including a nitrogen atom and an oxygen atom in their elemental compositions. The results suggested that the presence of oxygen atoms stabilizes [M + NH], but not every oxygen atom has enough energy for detection of [M + NH]. It was concluded that the nitrogen atom(s) and oxygen atom(s) in the elemental compositions play important roles in the adduct formation in direct analysis in real time mass spectrometry.

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