Noble Metal Nanoparticles Networks Stabilized by Rod‐Like Organometallic Bifunctional Thiols

od-like organometallic dithiol containing square-planar Pt(II) centers, i. e., trans,trans- [(H3COCS)Pt(PBu3)2(C�C C6H4 C6H4 C�C)(PBu3)2Pt(SCOCH3)] was used as bifunctional stabilizing agent for the synthesis of Pd-, Au-, and AgNPs (MNPs). All the MNPs showed diameters of about 4 nm, which can be controlled by carefully modulating the synthesis parameters. Covalent MNPs stabilization occurred through a single S bridge between Pt(II) and the noble metal nanocluster surfaces, leading to a network of regularly spaced NPs with the formation of dyads, as supported by SR-XPS data and by TEM imaging analysis. The chemical nature of NPs systems was also confirmed by EDS and NMR. Comparison between SR-XPS data of MNPs and self-assembled monolayers and multilayers of pristine rod-like dithiols deposited onto polycrystalline gold surfaces revealed an electronic interaction between Pt(II) centers and biphenyl moieties of adjacent ligands, stabilizing the organic structure of the network. The possibility to obtain networks of regularly spaced MNPs opens outstanding perspectives in optoelectronics

Congelação de espermatozoides epididimários de gatos utilizando o diluidor Botu-crio® após refrigeração por 24 h em contêiner de transporte de sêmen Botu-tainer®

The possibilities of using the sperm collected from the epididymis have been widely used because the fertilizing capacity sperm preservation and the possibility of using it for wild cats. But in the process of cryopreservation, some studies show a decrease in the quality of the sperm when left under cooling before frozen for some time. This study aimed to assess the quality of the epididymal sperm obtained from domestic cats after cryopreservation using a diluent based on egg yolk and glycerol (Botu-crio®), comparing the morphofunctional characteristics after cooling for 24 hours in a container of semen transport (Botu-tainer®). We use eight cats submitted to elective orchiectomy, aging from eight months, without racial determination, and good nutritional status. These sperm characteristics were: motility, vigor, concentration, membrane integrity and morphology. It has been found, after statistical analysis, that the container of semen was able to maintain sperm viability, even for 24h. We also observed a significant decrease on all parameters after frozen, consequential, probably to thermal stress that occurs in processing. However, the percentage of membrane integrity after thawing shows good employability of the Botu-crio®, which viability is possible to perform in vitro fertilization, requiring higher ratings