Building Block Engineering toward Realizing High-Performance Electrochromic Materials and Glucose Biosensing Platform.

The molecular engineering of conjugated systems has proven to be an effective method for understanding structure-property relationships toward the advancement of optoelectronic properties and biosensing characteristics. Herein, a series of three thieno[3,4-]pyrrole-4,6-dione (TPD)-based conjugated monomers, modified with electron-rich selenophene, 3,4-ethylenedioxythiophene (EDOT), or both building blocks (, , and ), were synthesized using Stille cross-coupling and electrochemically polymerized, and their electrochromic properties and applications in a glucose biosensing platform were explored. The influence of structural modification on electrochemical, electronic, optical, and biosensing properties was systematically investigated.

Selenophene-Modified Boron Dipyrromethene-Based Photosensitizers Exhibit Photodynamic Inhibition on a Broad Range of Bacteria.

Microorganisms are crucial for human survival in view of both mutualistic and pathogen interactions. The control of the balance could be achieved by use of the antibiotics. There is a continuous arms race that exists between the pathogen and the antibiotics.

Locked and Loaded: β-Galactosidase Activated Photodynamic Therapy Agent Enables Selective Imaging and Targeted Treatment of Glioblastoma Multiforme Cancer Cells.

Selective detection and effective therapy of brain cancer, specifically, the very aggressive glioblastoma multiforme (GBM), remains one of the paramount challenges in clinical settings. While radiotherapy combined surgery is proposed as the main treatment course, it has several drawbacks such as complexity of the operation and common development of recurrent tumors in this course of patient care. Unique opportunities presented by photodynamic therapy (PDT) offer promising, effective, and precise therapy against GBM cells along with simultaneous imaging opportunities.

Activity-Based Photosensitizers with Optimized Triplet State Characteristics Toward Cancer Cell Selective and Image Guided Photodynamic Therapy.

Activity-based theranostic photosensitizers are highly attractive in photodynamic therapy as they offer enhanced therapeutic outcome on cancer cells with an imaging opportunity at the same time. However, photosensitizers (PS) cores that can be easily converted to activity-based photosensitizers (aPSs) are still quite limited in the literature. In this study, we modified the dicyanomethylene-4-chromene (DCM) core with a heavy iodine atom to get two different PSs (DCM-I, I-DCM-Cl) that can be further converted to aPS after simple modifications.

A Nonionic Alcohol Soluble Polymer Cathode Interlayer Enables Efficient Organic and Perovskite Solar Cells.

The choice of interfacial materials and their properties play a critical role in determining solar cell performance and stability. For compatibility with roll-to-roll printing, it is desirable to develop stable cathode interface layers (CILs) that can be processed over the photoactive layer using orthogonal solvents. In this study, an -type naphthalene diimide core and oligo (ethylene glycol) side-chain-based conjugated polymer is reported as a universal, efficient CIL for organic and perovskite photovoltaics.

Balanced Intersystem Crossing in Iodinated Silicon-Fluoresceins Allows New Class of Red Shifted Theranostic Agents.

Iodination of the silicon-fluorescein core revealed a new class of highly cytotoxic, red-shifted and water-soluble photosensitizer (SF-I) which is also fairly emissive to serve as a theranostic agent. Singlet oxygen generation capacity of SF-I was evaluated chemically, and up to 45% singlet oxygen quantum yield was reported in aqueous solutions. SF-I was further tested in triple negative breast (MDA MB-231) and colon (HCT-116) cancer cell lines, which are known to have limited chemotherapy options as well as very poor prognosis.

Resorufin Enters the Photodynamic Therapy Arena: A Monoamine Oxidase Activatable Agent for Selective Cytotoxicity.

A red-absorbing, water-soluble, and iodinated resorufin derivative () that can be selectively activated with a monoamine oxidase (MAO) enzyme was synthesized, and its potential as a photodynamic therapy (PDT) agent was evaluated. showed high O generation yields in aqueous solutions upon addition of MAO isoforms, and it was further tested in cell culture studies. induced photocytotoxicity after being triggered by endogenous MAO enzyme in cancer cells with a much higher efficiency in SH-SY5Y neuroblastoma cells with high MAO-A expression.

Mitochondria-Targeting Selenophene-Modified BODIPY-Based Photosensitizers for the Treatment of Hypoxic Cancer Cells.

Two red-absorbing, water-soluble and mitochondria (MT)-targeting selenophene-substituted BODIPY-based photosensitizers (PSs) were realized (BOD-Se, BOD-Se-I), and their potential as photodynamic therapy (PDT) agents were evaluated. BOD-Se-I showed higher O generation yield thanks to the enhanced heavy-atom effect, and this derivative was further tested in detail in cell culture studies under both normoxic and hypoxic conditions. BOD-Se-I not only effectively functioned under hypoxic conditions, but also showed highly selective photocytotoxicity towards cancer cells.

Synthesis of N-Bridged Pyrido[4,3-d]pyrimidines and Self-Assembly into Twin Rosette Cages and Nanotubes in Organic Media.

Two N-bridged pyrido[4,3-d]pyrimidine derivatives were synthesized toward realization of a self-assembled bis-rosette cage, in organic media. Starting from commercially available malononitrile dimer and dimethyl 5-aminoisophthalate, the target molecules were synthesized in 11 steps using a convergent approach. The final bridged compounds were characterized by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry.

Synergistic Effects in Bimetallic Palladium-Copper Catalysts Improve Selectivity in Oxygenate Coupling Reactions.

Condensation reactions such as Guerbet and aldol are important since they allow for C-C bond formation and give higher molecular weight oxygenates. An initial study identified Pd-supported on hydrotalcite as an active catalyst for the transformation, although this catalyst showed extensive undesirable decarbonylation. A catalyst containing Pd and Cu in a 3:1 ratio dramatically decreased decarbonylation, while preserving the high catalytic rates seen with Pd-based catalysts.

A Novel Acetylcholinesterase Biosensor: Core-Shell Magnetic Nanoparticles Incorporating a Conjugated Polymer for the Detection of Organophosphorus Pesticides.

To construct a sensing interface, in the present work, a conjugated polymer and core-shell magnetic nanoparticle containing biosensor was constructed for the pesticide analysis. The monomer 4,7-di(furan-2-yl)benzo[c][1,2,5]thiadiazole (FBThF) and core-shell magnetic nanoparticles were designed and synthesized for fabrication of the biosensing device. The magnetic nanoparticles were first treated with silica and then modified using carboxyl groups, which enabled binding of the biomolecules covalently.

Upgrading Lignocellulosic Products to Drop-In Biofuels via Dehydrogenative Cross-Coupling and Hydrodeoxygenation Sequence.

Life-cycle analysis (LCA) allows the scientific community to identify the sources of greenhouse gas (GHG) emissions of novel routes to produce renewable fuels. Herein, we integrate LCA into our investigations of a new route to produce drop-in diesel/jet fuel by combining furfural, obtained from the catalytic dehydration of lignocellulosic pentose sugars, with alcohols that can be derived from a variety of bio- or petroleum-based feedstocks. As a key innovation, we developed recyclable transition-metal-free hydrotalcite catalysts to promote the dehydrogenative cross-coupling reaction of furfural and alcohols to give high molecular weight adducts via a transfer hydrogenation-aldol condensation pathway.

Novel pathways for fuels and lubricants from biomass optimized using life-cycle greenhouse gas assessment.

Decarbonizing the transportation sector is critical to achieving global climate change mitigation. Although biofuels will play an important role in conventional gasoline and diesel applications, bioderived solutions are particularly important in jet fuels and lubricants, for which no other viable renewable alternatives exist. Producing compounds for jet fuel and lubricant base oil applications often requires upgrading fermentation products, such as alcohols and ketones, to reach the appropriate molecular-weight range.

Production of an acetone-butanol-ethanol mixture from Clostridium acetobutylicum and its conversion to high-value biofuels.

Clostridium acetobutylicum is a bacterial species that ferments sugar to a mixture of organic solvents (acetone, butanol and ethanol). This protocol delineates a methodology to combine solventogenic clostridial fermentation and chemical catalysis via extractive fermentation for the production of biofuel blendstocks. Extractive fermentation of C.

Chemocatalytic upgrading of tailored fermentation products toward biodiesel.

Biological and chemocatalytic processes are tailored in order to maximize the production of sustainable biodiesel from lignocellulosic sugar. Thus, the combination of hydrotalcite-supported copper(II) and palladium(0) catalysts with a modification of the fermentation from acetone-butanol-ethanol to isopropanol-butanol-ethanol predictably produces higher concentrations of diesel-range components in the alkylation reaction.

Synthesis of N-substituted pyrido[4,3-d]pyrimidines for the large-scale production of self-assembled rosettes and nanotubes.

N-substituted pyrido[4,3-d]pyrimidines are heterocycles which exhibit the asymmetric hydrogen bonding codes of both guanine and cytosine at 60° angles to each other, such that the molecules self-organize unambiguously into a cyclic hexamer, assembled via 18 intermolecular hydrogen bonds. The synthesis is straightforward and can be concluded in six steps from the commercially available malononitrile dimer. X-ray crystallographic analysis of the supermacrocyclic structure shows an undulating disk with a ca.

Extraordinary modes of bonding enabled by the triquinane framework.

Incorporation of triquinane ring systems into a macrobicyclic framework enables the stabilization of unusual bonding arrangements, including 3-center-2-electron cation, 3-center-3-electron radical, and 3-center-4-electron anion systems, linear divalent fluorine, triplet carbenes, record short C-C bonds, a powerful proton sponge effect, and oxadionium (R4O(2+)) ions. The means to stabilize and conceivably isolate such species derives from the rigid, convex nature of the triquinane ring system, as well as the substitution of positions adjacent to the bridgeheads atoms which would otherwise be vulnerable to elimination. The potential realization of hitherto undescribed bonding outcomes makes these macrocycles provocative synthetic targets.

Extreme oxatriquinanes: structural characterization of α-oxyoxonium species with extraordinarily long carbon-oxygen bonds.

The first stable α-oxyoxonium species have been synthesized and characterized. Strong donation of nonbonding electrons on oxygen into the adjacent σ*(C-O(+)) orbital was predicted by modeling to result in unheard of carbon-oxygen bond lengths. The kinetic stability of the triquinane ring system provides a platform upon which to study these otherwise elusive species, which are evocative of intermediates on the acetalization reaction pathway.

Extreme oxatriquinanes and a record C-O bond length.

Oxatriquinanes are fused, tricyclic oxonium ions that are known to have exceptional stability compared to simple alkyl oxonium salts. C-O bonds in ethers are generally ∼1.43 Å in length, but oxatriquinane has been found to have C-O bond lengths of 1.

The R3O+···H+ hydrogen bond: toward a tetracoordinate oxadionium(2+) ion.

Oxatriquinanes are tricyclic oxonium ions which are known to possess remarkable solvolytic stability compared to simple alkyl oxonium salts. Their rigid, hemispherical structure presents an oxygen at the apex of three fused five-membered rings. While trivalent oxygen species like these have been well described in the literature, the ability of oxygen to enter into a fourth covalent bonding relationship has been visited in theory and suggested by the outcome of certain reactions conducted in superacidic media, but has never been established by the characterization of a stable, persistent R(3)OH(2+) or R(4)O(2+) ion.

Electrochromic conjugated polyheterocycles and derivatives--highlights from the last decade towards realization of long lived aspirations.

Polymer electrochromism has been considered one of the liveliest branches of conducting polymer research, a tradition continued in the last decade. We have witnessed numerous significant advances, making commercial applications closer than ever. This feature article highlights these advances by separating them into 3 sections.

One polymer for all: benzotriazole containing donor-acceptor type polymer as a multi-purpose material.

A polymer switching between all RGB colors, black and transmissive states was synthesized. The polymer (PTBT) is soluble, processable, both p- and n-dopable, fluorescent and its properties in entire spectrum offer potential uses in NIR devices, LEDs and solar cells. PTBT possesses almost all properties in a single polymer for optoelectronic applications.

A neutral state green polymer with a superior transmissive light blue oxidized state.

This report highlights the synthesis of only the second green polymer in the literature, which possesses superior properties over the first: a highly transmissive light blue color in the oxidized state with high optical contrast and excellent switching properties.