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The intracellular distribution of fluorescently labeled copper and zinc bis(thiosemicarbazonato) complexes was investigated in M17 neuroblastoma cells and primary cortical neurons with a view to providing insights into the neuroprotective activity of a copper bis(thiosemicarbazonato) complex known as Cu(II)(atsm). Time-resolved fluorescence measurements allowed the identification of the Cu(II) and Zn(II) complexes as well as the free ligand inside the cells by virtue of the distinct fluorescence lifetime of each species. Confocal fluorescent microscopy of cells treated with the fluorescent copper(II)bis(thiosemicarbazonato) complex revealed significant fluorescence associated with cytoplasmic puncta that were identified to be lysosomes in primary cortical neurons and both lipid droplets and lysosomes in M17 neuroblastoma cells. Fluorescence lifetime imaging microscopy confirmed that the fluorescence signal emanating from the lipid droplets could be attributed to the copper(II) complex but also that some degree of loss of the metal ion led to diffuse cytosolic fluorescence that could be attributed to the metal-free ligand. The accumulation of the copper(II) complex in lipid droplets could be relevant to the neuroprotective activity of Cu(II)(atsm) in models of amyotrophic lateral sclerosis and Parkinson's disease.

Paper-based diagnostics provide a low-cost, reliable and easy to use mode of blood typing. The shelf-life of such products, however, can be limited due to the reduced activity of reagent antibodies sorbed on the paper cellulose fibers. This study explores the effects of aging on antibody activity for periods up to 12 months on paper and in solution under different aging and drying conditions—air-dried, lyophilized, and kept as a liquid. Paper kept wet with undiluted antibody is shown to have the longest shelf-life and the clearest negatives. Antibody diluted with bovine serum albumin (BSA) protects against the lyophilization process, however, beyond 9 months aging, false positives are seen. Paper with air-dried antibodies is not suitable for use after 1 month aging. These results inform preparation and storage conditions for the development of long shelf-life blood grouping paper-based diagnostics.

We present the first experimental demonstration of the astigmatic phase retrieval technique, in which the diffracted wavefield is distorted by cylindrical curvature in two orthogonal directions. A charge-one vortex, a charge-two vortex, and a simple test image are all correctly reconstructed.