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Damage of DNA films after reaction with styrene oxide was detected using derivative square wave voltammetry. Double-stranded (ds) DNA films with initially low backgrounds developed oxidation peaks for DNA bases during incubation with styrene oxide. Films were prepared on pyrolytic graphite (PG) electrodes by casting mixtures of DNA with the poly(ester sulfonic acid) ionomer Eastman AQ38S or by covalent binding of DNA onto oxidized PG. While both types of films gave oxidation peaks in the region 0.6-1.1 V vs SCE after incubations with styrene oxide, DNA/AQ films gave the best signal-to-background ratios. Damage of DNA by reaction with styrene oxide under the electrode incubation conditions was confirmed by capillary electrophoresis. Total integrals of oxidation peaks increased with time of incubation with styrene oxide. Relative peak heights depended on the type of DNA in the order calf thymus ds DNA > salmon sperm ds DNA > supercoiled ds DNA > highly polymerized calf thymus ds DNA.

Ni-Mn-Ga-X microwires were produced by melt-extraction technique on a large scale. Their shape memory effect, superelasticity, and damping capacity have been demonstrated. Here, the excellent magnetocaloric effect was revealed in Ni-Mn-Ga-Cu microwires produced by melt-extraction and subsequent annealing. The overlap of the martensitic and magnetic transformations, i.e., magnetostructural coupling, was achieved in the annealed microwires. The magnetostructural coupling and wide martensitic transformation temperature range contribute to a large magnetic entropy change of −8.3 J/kg K with a wide working temperature interval of ∼13 K under a magnetic field of 50 kOe. Accordingly, a high refrigeration capacity of ∼78 J/kg was produced in the annealed microwires.

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