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They show indeed that an incomplete check of such conditions can result in erroneous conclusions about the prevalent transport mechanisms.Many soft matter systems are composed of roughly spherical objects that can self-assemble in ordered structures. Unlike hard spheres, at high volume fraction these soft spheres adapt their shape to the local geometrical constraints and the question of space filling needs to be entirely revisited. Hydrophobically coated gold nanocrystals self-assemble in supercrystals and are good candidates to explore this question. When the soft coating is thin compared to the rigid core, a FCC structure is obtained, with a behaviour similar to that of hard spheres. In the opposite case, for a thick soft coating, a BCC structure is found instead. This paper focus on the intermediate region between these two classical structures. By varying the gold core radius R and the ligand fully extended length L, we establish a structure diagram based on a large experimental data set. The hexagonal Frank-Kasper C14 structure is observed for various values of R and L and can coexist with a FCC phase. Depending on the structure, values of the minimum thickness e of the ligand shell compared to L are different. These experimental results confirm that the C14 Frank-Kasper phase is a solution to the problem of filling the space with soft particles even with a rigid core and should help to establish pertinent models in order to predict the structures of the superlattices built by gold nanoparticles.The coordination modes of the ligand 2,5,8-trithia[9](2,6)pyridinophane (L) to thallium(i), gold(iii) and gold(i) have been studied. Thallium(i) is coordinated by the macrocyclic ligand in [Tl(L)](PF6) (1) through all the sulfur and nitrogen atoms, in a distorted square-pyramidal geometry with the thallium(i) ion in the apical position and with the presence of an inert lone pair. Gold(iii) is bonded by the ligand only through the nitrogen of the pyridine group in [AuCl3(L)] (2), whereas two AuI-C6F5 fragments coordinate the sulfur atoms next to the pyridine moiety of the ligand in [Au(C6F5)2(μ-L)] (3), which form a linear polymer through intermolecular aurophilic contacts. The heterometallic TlI/AuI complex [Au(C6F5)2Tl]2(L)n (4) features a polymeric structural nature with a metallic pseudo-rhombic Au2Tl2 core, which repeats itself forming a zig-zag polymer. In each Au2Tl2 unit only one thallium atom is bonded by the NS3 donor set of the macrocyclic ligand and also forms two unsupported Au-Tl bonds with two [Au(C6F5)2]- units in an overall pseudo-octahedral geometry. The other thallium atom similarly bridges the same [Au(C6F5)2]- units and links a neighbouring Au2Tl2 moiety, thus exhibiting a distorted trigonal planar geometry being bonded only to three gold atoms with unsupported Au-Tl interactions. This complex displays an interesting thermochromic behaviour showing emissions mainly resulting from MM'CT transitions at room temperature. At 77 K a dual emission appears, probably arising from the two different thallium environments. DFT calculations have been carried out in the attempt to investigate the origin of the emissions of complex 4.Influenza A (H1N1) virus is a serious health threat and potential leading cause of death around the world during the processes of immunity and inflammation. Herein a sensitive pH-responsive point-of-care (POC) electrochemical immunoassay was designed for the quantitative monitoring of H1N1 influenza virus using glucose oxidase (GOx) and secondary antibody-functionalized Ti3C2-MXene nanosheets. The assay was carried out on the basis of the sandwich-type immunoreaction in the capture antibody-coated microplate. Two-dimensional (2D) Ti3C2-MXene nanosheets with a large surface area could efficiently enhance the loading amount of GOx molecules, thereby resulting in the signal amplification. Accompanying the formed immunocomplexes, labeled GOx molecules catalyzed glucose into gluconic acid and hydrogen peroxide. The generated gluconic acid caused a pH change of the detection solution, which was quantitatively determined on a handheld pH meter. Two labeling strategies with and without Ti3C2-MXene nanosheets were investigated to determine the target H1N1 influenza virus, and improved properties were acquired with the Ti3C2-MXene-labeled system. Under optimum conditions, the Ti3C2-MXene-based immunoassay gave good dynamic responses toward the target H1N1 influenza virus from 0.01 μg mL-1 to 100 μg mL-1 with a detection limit of 1.3 ng mL-1. Good reproducibility, high specificity, and acceptable stability were also achieved in the analysis of the target H1N1 influenza virus. Significantly, measurements of the H1N1 influenza virus from clinical human samples were demonstrated to further confirm the method reliability and accuracy of the Ti3C2-MXene-based electrochemical immunoassay. Importantly, such a pH-meter-based immunoassay can be suitable for use in point-of-care applications and opens new opportunities for diagnostics.The natural biomaterial sarcosine as an electron transport layer (ETL) to modify ITO or ITO/ZnO was successfully introduced into inverted organic solar cells (OSCs) with PM6BTP-BO-4Cl as the active layer. The introduction of sarcosine on the surface of ITO or ITO/ZnO resulted in lower work function (WF) and higher surface energy. The active layers processed on the surfaces of ITO or ITO/ZnO presented a more optimized morphology and a more ordered molecular arrangement after their modification with sarcosine. The introduction of sarcosine as an ETL promoted charge transport and collection in the OSCs. Therefore, the power conversion efficiency (PCE) of the OSCs increased to 13.53% from 3.86% by modifying ITO with sarcosine. The PCE of the OSCs with ZnO as ETLs improved to 16.45% from 14.85% by modifying ZnO with sarcosine. selleck chemicals llc The improved PCEs benefited from the simultaneously improved short-circuit current density (JSC), fill factor (FF), and open-circuit voltage (VOC). Therefore, this work demonstrates that sarcosine has great potential as an ETL to improve the performance of OSCs.Recently, carbon dots (CDs) have been widely investigated for biological applications in imaging. One-step hydrothermal synthesis is considered to be one of the most promising methods for the synthesis of CDs, due to its simple and rapid manipulation, flexible selection of ingredients, environmentally friendly conditions, and low-cost. A number of synthetic and post-synthetic parameters, including solvent, heating time, dopant quantity, and particle size distribution, play a crucial role in controlling the size and surface structure of CDs, which ultimately have influence on their photophysical and biological behavior. Despite the crucial role of each of these parameters in defining the yield and nature of synthesized CDs, they have not previously been rigorously optimized, particularly with respect to desired biological applications. Herein, we report our comprehensive optimization of the parameters employed for the hydrothermal synthesis of CDs to gain a better understanding of the effect of these parameters on optical properties, cytotoxicity, and cellular uptake efficiency.