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We present the structure of coiled coils found in two oligonucleotide DNA crystals. The sequences d-(ATATATATAT) and d(CGATATATAT) are used. In the first case several coiled coils with different structures are found. In the second case a single structure is present. The results are compared with other coiled coil structures. They might be used in the development of new nanomaterials.

Scientists have always been fascinated by transient far-from-equilibrium systems. Since the (early) 1970s, there have been literature reports on the implementation of didactic experiments as a tool for attracting and stimulating students’ and general public interest. In this work, a group of 12 high school students, supported by their chemistry teacher, have developed a supramolecular system formed by gold nanoparticles functionalized with a positively charged thiol group. The positively charged nanoparticles were aggregated by adding polyanionic ATP as fuel. Aggregates were determined by UV–vis spectroscopy. Disaggregation was realized by adding an enzyme capable of hydrolyzing the ATP P–O bonds. The lifetime of the aggregates depends on the enzyme concentration and efficiency. Several aggregation–disaggregation cycles were performed. Students were divided into three groups, each of four students. Teachers assigned different duties to each group. The first group synthesized and purified the gold nanoparticles and the capping thiolic group. The second group determined UV–vis optical properties of the nanosystem and implemented the conditions for further experiments. The third group performed experiments to characterize the nanosystem and its lifetime. At the time of this activity, all of the students were attending their last year at chemistry high school in Italy. As didactic goals, they have been trained in problem solving, the use of advanced lab instruments, and following and projecting their own research activity.

A class of 18 students attending the last year of an Italian high school was divided into groups and performed the extraction of pigments contained in hibiscus tea. Each group worked at a different temperature and carried out multiple extractions using distilled water as a solvent. By means of UV−vis spectroscopy it was possible to determine the yield of each individual extraction and then to study the effect of temperature on the extraction itself. The method is easy to implement, it does not require the use of hazardous reagents or special safety precautions, and it is very cheap. The laboratory part was carried out in 3 h time, while the analysis and data processing took about 4 h. On an educational level, the students learned to process and analyze large amounts of data, and they became familiar with the UV−vis spectrophotometer and eventually had to solve the problems independently.