Paraformaldehyde (PFA) is the most commonly used fixative for immunostaining of cells, but has been associated with various problems, ranging from loss of antigenicity to changes in morphology during fixation. We show here that the small dialdehyde glyoxal can successfully replace PFA. Despite being less toxic than PFA, and, as most aldehydes, likely usable as a fixative, glyoxal has not yet been systematically tried in modern fluorescence microscopy. Here, we tested and optimized glyoxal fixation and surprisingly found it to be more efficient than PFA‐based protocols. Glyoxal acted faster than PFA, cross‐linked proteins more effectively, and improved the preservation of cellular morphology. We validated glyoxal fixation in multiple laboratories against different PFA‐based protocols and confirmed that it enabled better immunostainings for a majority of the targets. Our data therefore support that glyoxal can be a valuable alternative to PFA for immunostaining.

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We report on a novel resonant THz sensor for the label-free analysis of DNA molecules. The sensor allows the direct detection of DNA-probe molecules at functionalized electrodes via hybridization. Subsequent time resolved photoconductive sampling of the THz transmission identifies the binding state between probe and target DNA. Integrating neighbouring sensors on a chip, this technique can be extended to a parallel analysis of multiple DNA sequences. A clearly readable sensor response is obtained with less then 40 fmol of 20-mer single-stranded DNA molecules, indicating at least a sevenfold sensitivity increase compared to previous approaches.

This review summarizes the past present, and future developments of isocyanate chemistry for polyurethane coatings and adhesives. Over the past 60 years, this field was driven by numerous breakthrough innovations that helped improve coating applications with respect to customer's needs—cementing the features of this outstanding material class. We provide a short introduction on the early beginnings of industrial isocyanate chemistry and then a detailed overview on the building blocks as well as the rich chemistry of the isocyanate group. The synthesis of various derivatives is described. An outlook on the latest developments—new building blocks and new chemistries—is given in the field of isocyanate coating and adhesive chemistry. © 2018 Society of Chemical Industry