While the Staudinger reaction has first been described a hundred years ago in 1919, the ligation reaction became one of the most important and efficient bioconjugation techniques in the 1990s and this century. It holds the crucial characteristics for bioorthogonal chemistry: biocompatibility, selectivity, and a rapid and high-yielding turnover for a wide variety of applications. In the past years, it has been used especially in chemical biology for peptide/protein synthesis, posttranslational modifications, and DNA labeling. Furthermore, it can be used for cell-surface engineering, development of microarrays, and drug delivery systems. However, it is also possible to use the reaction in synthetic chemistry for general formation of amide bonds. In this review, the three major types, traceless and nontraceless Staudinger Ligation as well as the Staudinger phosphite reaction, are described in detail. We will further illustrate each reaction mechanism and describe characteristic substrates, intermediates, and products. In addition, not only its advantages but also stereochemical aspects, scope, and limitations, in particular side reactions, are discussed. Finally, the method is compared to other bioorthogonal labeling methods.

Small molecule high-throughput screenings are essential for the fields of drug discovery and toxicology. Such screenings performed on whole animals are more physiologically relevant leading to more predictive results. However, due to challenges in automation, high costs and absence of miniaturized solutions for animal-based experiments, high throughput screenings based on animal models are still in its infancy. Here a platform for miniaturized high throughput whole-organism screenings is presented. The new platform is based on patterns of hydrophilic spots separated by superhydrophobic borders. The difference in wettability of spots and borders generates the effect of discontinuous dewetting and allows for formation of arrays of microdroplets that incorporate single fish embryos. Due to the flat border-less nature of the platform, the system is compatible with single-step collection of embryos and pipetting-free parallel addition of chemical libraries using the "sandwiching method." The system is miniaturized and allows for incubation of embryos in volumes as low as 5 µL. Finally, the platform realizes surface tension based immobilization of single embryos inside of each microcompartment and permits high-throughput microscopic analysis directly on the platform. Thus, this method combines the advantages of microarrays, such as highthroughput and simplicity, with the power of in vivo experiments. Fish-Microarrays

In this communication, the synthesis of three unknown polyfluorinated cyanine dyes and their application as selective markers for mitochondria are presented. By incorporating fluorous side chains into cyanine dyes, their remarkable photophysical properties were enhanced. To investigate their biological application, several different cell lines were incubated with the synthesized cyanine dyes. It was discovered that the presented dyes can be utilized for selective near‐infrared‐light (NIR) staining of mitochondria, with very low cytotoxicity determined by MTT assay. This is the first time that polyfluorinated cyanine fluorophores are presented as selective markers for mitochondria. Due to the versatile applications of polyfluorinated fluorophores in bioimaging and materials science, it is expected that the presented fluorophores will be stimulating for the scientific community.

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