While the solution‐phase synthesis of directly fused porphyrin tapes has been successfully developed in recent years, the deposition of these promising compounds in thin film form has remained a challenge. In this study, we report the simultaneous synthesis and deposition of conductive directly fused poly(porphyrin) coatings based on a substrate independent and up‐scalable oxidative chemical vapor deposition (oCVD) approach. A particular emphasis is given to the selection and sublimation conditions of the oxidant. The direct fusion of nickel(II) 5,15‐(diphenyl)porphyrin (NiDPP) is successfully achieved using three different oxidants, namely iron(III) chloride (FeCl3), copper(II) chloride (CuCl2) and copper(II) perchlorate hexahydrate (Cu(ClO4)2·6H2O). FeCl3 is demonstrated as the most suitable oxidant, allowing the formation of mainly singly‐fused poly(NiDPP) or conductive mainly doubly or triply‐fused poly(NiDPP) that strongly absorb in the NIR. High‐resolution mass spectrometry evidences the chlorination of the formed compounds as a side reaction. This chlorination can either be considered as a drawback by preventing the formation of large directly fused NiDPP oligomers or as an asset when targeting the formation of fully insoluble directly fused poly(NiDPP) coatings. Overall, the described oCVD approach opened up the possibility to tune the band gap, conductivity, and solubility of directly fused P(NiDPP) coatings.

Despite being a critical molecule in the brain, mass spectrometry imaging (MSI) of cholesterol has been under-reported compared to other lipids due to the difficulty in ionizing the sterol molecule. In the present work, we have employed an on-tissue enzyme-assisted derivatization strategy to improve detection of cholesterol in brain tissue sections. We report distribution and levels of cholesterol across specific structures of the mouse brain, in a model of Niemann-Pick type C1 disease, and during brain development. MSI revealed that in the adult mouse, cholesterol is the highest in the pons and medulla and how its distribution changes during development. Cholesterol was significantly reduced in the corpus callosum and other brain regions in the Npc1 null mouse, confirming hypomyelination at the molecular level. Our study demonstrates the potential of MSI to the study of sterols in neuroscience.

Coatings consisting in gentamicin-containing nanocapsules have been synthetized by means of an aerosol-assisted atmospheric pressure plasma deposition process. The influence of different parameters affecting the process has been extensively investigated by means of a morphological and chemical characterization of the coatings. Scanning electron microscopy highlighted the presence of nanocapsules whose size and abundance depend on power input and deposition time. A detailed analysis carried out with matrix-assisted laser desorption ionization coupled to high-resolution mass spectrometry allowed to detect and identify the presence of gentamicin embedded in the coatings and its rearrangement, as a result of the interaction with the plasma. The release of gentamicin in water has been monitored by means of UV-vis fluorescence spectroscopy, and its biological activity has been evaluated as well by the disk diffusion assay against Staphylococcus aureus and Pseudomonas aeruginosa. It is confirmed that the antibacterial activity of gentamicin is preserved in the plasma-deposited coatings. Preliminary cytocompatibility investigations indicated that eukaryotic cells well tolerate the release of gentamicin from the coatings.

Porous and highly conjugated multiply fused porphyrin thin films are prepared from a fast and single-step chemical vapor deposition approach. While the solution-based coupling of porphyrins is usually undertaken at room temperature, the gas phase reaction of nickel(II) 5,15-(diphenyl)porphyrin and iron(III) chloride (FeCl 3 ) is investigated for temperatures as high as 200 °C. Helium ion and atomic force microscopy, supported by weight and thickness measurements, shows a drastic decrease of the fused porphyrin thin film’s density accompanied by the formation of a mesoporous morphology upon increase of the reaction temperature. The increase of the film’s porosity is attributed to formation of a greater amount of HCl (originated from both the oxidative coupling and chlorination reactions) and the release of gaseous FeCl 3 byproducts, i.e., Cl 2 , at higher deposition temperatures. In addition, high resolution mass spectrometry reveals that increase of the reaction temperature promotes a higher degree of conjugation of the fused porphyrins chains, which ensures that high electronic conductivities are maintained along with high porosity. The method reported herein could enable the engineering of fused porphyrin thin films in sensing and catalytic devices.

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Despite being a critical molecule for neurobiology and brain health, mass spectrometry imaging (MSI) of cholesterol has been under reported compared to other lipids, due to the difficulty in ionising the sterol molecule. In the present work we have employed an on-tissue enzyme-assisted derivatisation strategy to improve detection of cholesterol in brain tissue sections. We report distribution and levels of cholesterol across specific brain structures of the mouse brain, in a model of Niemann-Pick type C1 (NPC1) disease, and during brain development. MSI revealed how cholesterol changes during development and that in the adult is highest in pons and medulla of the brain stem. Cholesterol was significantly reduced in the corpus callosum and other brain regions in the Npc1 null mouse, confirming hypomyelination at the molecular level. Our study demonstrates the potential of MSI to the study of sterols in neuroscience.

Treatment with ruxolitinib cream (Janus kinase [JAK] 1/JAK2 inhibitor) in adult patients with vitiligo resulted in substantial repigmentation over 52 weeks in a phase 2 dose-ranging study (NCT03099304). We assessed maintenance of repigmentation among responders from the phase 2 study following ruxolitinib discontinuation after 104 weeks of treatment. Patients initially randomized to ruxolitinib cream (1.5% twice daily [BID], 1.5% once daily [QD], 0.5% QD, or 0.15% QD) with evidence of facial repigmentation at Week 24 who completed 1 follow-up visit 1, 3, or 6 months after an additional 52 weeks of 1.5% ruxolitinib cream BID (Weeks 52e104) were analyzed. Loss of repigmentation was defined as an increase in Vitiligo Area Severity Index score during the last follow-up visit vs Week 104 on ruxolitinib cream. The analysis included 16 patients (1.5% BID, n¼3; 1.5% QD, n¼5; 0.5% QD, n¼3; 0.15% QD, n¼5 [including 2 patients rerandomized to 1.5% BID/0.5% QD after Week 24]). Twelve patients (75.0%) maintained total body repigmentation and 13 (81.3%) maintained facial repigmentation during follow-up of 1e6 months; no patients from the 1.5% ruxolitinib BID treatment group (with 2 years' exposure) experienced repigmentation loss. There were no significant differences in baseline serum levels of chemokine (C-X-C motif) ligand (CXCL) 9, CXCL10, or interleukin-15 in patients who experienced loss vs maintenance of repigmentation after ruxolitinib cream discontinuation. This exploratory analysis suggests that some repigmentation with ruxolitinib cream may be maintained post-discontinuation; larger follow-up studies are required to confirm these findings.