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The use of photoactivatable dyes in STED microscopy has so far been limited by two‐photon activation through the STED beam and by the fact that photoactivatable dyes are poorly solvable in water. Herein, we report ONB‐2SiR, a fluorophore that can be both photoactivated in the UV and specifically de‐excited by STED at 775 nm. Likewise, we introduce a conjugation and purification protocol to effectively label primary and secondary antibodies with moderately water‐soluble dyes. Greatly reducing dye aggregation, our technique provides a defined and tunable degree of labeling, and improves the imaging performance of dye conjugates in general., ONB‐2SIR, a photoactivatable dye resistant against two‐photon uncaging by 775 nm STED light is synthesized and used to perform STED microscopy before and after photoactivation without undesired activation by the STED light. The effects of the low water‐solubility of ONB‐2SIR on antibody conjugation was overcome by glycan labelling with defined degree of labelling (DOL) and a phase separation purification method.

Cobalt‐doped zinc oxide single crystals with the shape of hexagonal platelets were synthesized by thermohydrolysis of zinc acetate, cobalt acetate, and hexamethylenetetramine (HMTA) in mixtures of ethanol and water. The mineralization proceeds by a low‐temperature dissolution–reprecipitation process from the liquid phase by the formation of basic cobalt zinc salts as intermediates. The crystal shape as well as twin formation of the resulting oxide phase can be influenced by careful choice of the solvent mixture and the amount of doping. An understanding of the course of the reaction was achieved by comprehensive employment of analytical techniques (i.e., SEM, XRD, IR) including an in‐depth HRTEM study of precipitates from various reaction stages. In addition, EPR as well as UV/Vis spectroscopic measurements provide information about the insertion of the cobalt dopant into the zincite lattice. The Langmuir–Blodgett (LB) technique is shown to be suitable for depositing coatings of the platelets on glass substrates functionalized with polyelectrolyte multilayers and hence is applied for the formation of monolayers containing domains with ordered tessellation. No major differences are found between deposits on substrates with anionic or cationic surface modification. The adherence to the substrates is sufficient to determine the absolute orientation of the deposited polar single crystals by piezoresponse force microscopy (PFM) and Kelvin probe force microscopy (KPFM) studies., Crystal shape: Doping is an effective way to control crystal shape in mineralization processes. Studying the synthesis of single‐crystalline hexagonal platelets of Co‐doped ZnO with advanced high‐resolution transmission electron microscopy (HRTEM) techniques can hereby provide an instructive insight into the details of the formation mechanism.

Chemical or electrochemical one‐electron oxidation of 5‐N‐arylaminothiazoles was found to afford stable radical cations. For chemical oxidation, 1 equivalent of [(4‐BrC6H4)3N][SbCl6] (Magic Blue, MB) was added to CH2Cl2 solutions of the thiazoles, and the thus‐obtained radicals showed light absorption in the near‐infrared region. Electrochemical oxidation also led to bathochromic shifts in the absorption bands, and the obtained spectra were similar to those derived from the chemically oxidized species. These radicals afforded electron paramagnetic resonance (EPR) spectra that are consistent with the notion of stable nitrogen radicals (half‐life≤385 h). The EPR spectrum of a thiazole containing 4‐dimethylaminophenyl groups on the nitrogen atom at the 5‐position changed significantly upon adding >3 equivalents of MB. Details of the electronic structures of the experimentally obtained radical cations were generated from theoretical calculations.