Ismael López-Duarte

Ruthenium phthalocyanine (RuPcs) are multipurpose compounds characterized by their remarkable reactivity and photoelectronic properties, which yield a broad synthetic scope and easy derivatization at the axial position. However, RuPcs have been underexplored for use in organic thin‐film transistors (OTFTs), and therefore new studies are necessary to provide basic insight and a first approach in this new application. Herein, two novel RuPc derivatives, containing axial pyridine substituents with aliphatic chains (RuPc(CO)(PyrSiC6) (1) and RuPc(PyrSiC6)₂ (2), were synthesized, characterized, and tested as the organic semiconductor in OTFTs. RuPc thin‐films were characterized by X‐ray diffraction (XRD), and atomic force microscopy (AFM) to assess film morphology and microstructure. 1 displayed comparable p‐type device performance to other phthalocyanine‐based OTFTs of similar design, with an average field effect mobility of 2.08×10⁻³ cm² V⁻¹ s⁻¹ in air and 1.36×10⁻³ cm² V⁻¹ s⁻¹ in nitrogen, and threshold voltages from −11 V to −20 V. 2 was found to be non‐functional as the semiconductor in the device architecture used, likely as a result of significant differences in thin‐film formation. The results of this work illustrate a promising starting point for future development of RuPc electronic devices, particularly in this new family of OTFTs.

In the present work, the energy donor 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) is used for the first time in combination with a pentacene dimer (Pnc₂) to provide the conjugate BODIPYPnc₂ that features absorption throughout a large part of the solar spectrum. Upon photoexcitation, the singlet excited state energy of BODIPY is transferred to the pentacene dimer via intramolecular Förster resonance energy transfer (FRET). Subsequently, the pentacene dimer undergoes intramolecular singlet fission. In this process, a singlet correlated triplet pair is generated from the first singlet excited state via coupling to an intermediate state. The results show that solvent polarity has an influence on the system, with the largest FRET rate (i.e., 7.46 × 10¹¹ s⁻¹) being obtained in the most polar solvent (namely, benzonitrile) along with the largest triplet quantum yield (i.e., 207 ± 20%).

Lipid peroxidation is a process which is key in cell signaling and disease, it is exploited in cancer therapy in the form of photodynamic therapy. The appearance of hydrophilic moieties within the bilayer’s hydrocarbon core will dramatically alter the structure and mechanical behavior of membranes. Here, we combine viscosity sensitive fluorophores, advanced microscopy, and X-ray diffraction and molecular simulations to directly and quantitatively measure the bilayer’s structural and viscoelastic properties, and correlate these with atomistic molecular modelling. Our results indicate an increase in microviscosity and a decrease in the bending rigidity upon peroxidation of the membranes, contrary to the trend observed with non-oxidized lipids. Fluorescence lifetime imaging microscopy and MD simulations give evidence for the presence of membrane regions of different local order in the oxidized membranes. We hypothesize that oxidation promotes stronger lipid-lipid interactions, which lead to an increase in the lateral heterogeneity within the bilayer and the creation of lipid clusters of higher order.

This review summarizes the recent advances in light driven catalytic H₂evolution and CO₂reduction systems towards the production of solar fuels, utilizing porphyrin or phthalocyanine derivatives.

Misfolding of secretory proteins in the endoplasmic reticulum (ER) features in many human diseases. In α ₁ -antitrypsin deficiency, the pathogenic Z variant aberrantly assembles into polymers in the hepatocyte ER, leading to cirrhosis. We show that α ₁ -antitrypsin polymers undergo a liquid:solid phase transition, forming a protein matrix that retards mobility of ER proteins by size-dependent molecular filtration. The Z-α ₁ -antitrypsin phase transition is promoted during ER stress by an ATF6-mediated unfolded protein response. Furthermore, the ER chaperone calreticulin promotes Z-α ₁ -antitrypsin solidification and increases protein matrix stiffness. Single-particle tracking reveals that solidification initiates in cells with normal ER morphology, previously assumed to represent a healthy pool. We show that Z-α ₁ -antitrypsin–induced hypersensitivity to ER stress can be explained by immobilization of ER chaperones within the polymer matrix. This previously unidentified mechanism of ER dysfunction provides a template for understanding a diverse group of related proteinopathies and identifies ER chaperones as potential therapeutic targets.

A BODIPY molecular rotor can be used to evaluate the viscosity of collagen-like peptide-PEG solutions.

Viscosity, a reciprocal of fluidity, plays an important role in the functioning of living cells, as it is one of the key parameters for the regulation of their morphological and physiological state. In particular, the viscosity of the cytoplasmic membrane is thought to be involved in controlling the transport of molecules, permeability, biosynthesis, and catalytic activity of membrane enzymes.¹

A novel tetrabenzotriazaporphyrin (TBTAP) bearing an anchoring carboxy‐phenyl group at the meso‐carbon position (TT260) was synthesized by an efficient method, which involves the crossover condensation between phthalonitrile and aminoisoindoline precursors. Its optical and electrochemical properties were also investigated together with its use as sensitizer in dye‐sensitized solar cells (DSSCs). The performance of TT260 was compared with a benchmark molecule TT1, bearing similar bulky tert‐butyl groups at the periphery. The device, which is the first ever example of meso‐substituted TBTAP‐based DSSC, exhibits a modest maximum power conversion efficiency of 2.4±0.1 % under one‐sun conditions.

Different co-crystals from N-hetero-tolane derivatives are prepared by hydrogen- or halogen-bonding. Their crystal structures have been determined by single crystal X-ray diffraction (SCXRD). Highly ordered smectic liquid crystals are obtained upon protonation of compound 1 and show a remarkable thermal stability. All supramolecular aggregates, crystalline or liquid crystalline, are characterized accordingly by X-ray diffraction (XRD), polarized optical microscopy (POM), and thermal analysis (DSC).

We present organic, diamagnetic materials based on structurally simple (hetero-)tolane derivatives. They form crystalline thin-film aggregates that are suitable for Faraday rotation (FR) spectroscopy. The resulting new materials are characterized appropriately by common spectroscopic (NMR, UV-Vis), microscopy (POM), and XRD techniques. The spectroscopic studies give extremely high FR activities, thus making these materials promising candidates for future practical applications. Other than a proper explanation, we insist on the complexity of designing efficient FR materials starting from single molecules.