Identifying high-grade serous ovarian carcinoma-specific extracellular vesicles by polyketone-coated nanowires.

Cancer cell-derived extracellular vesicles (EVs) have unique protein profiles, making them promising targets as disease biomarkers. High-grade serous ovarian carcinoma (HGSOC) is the deadly subtype of epithelial ovarian cancer, and we aimed to identify HGSOC-specific membrane proteins. Small EVs (sEVs) and medium/large EVs (m/lEVs) from cell lines or patient serum and ascites were analyzed by LC-MS/MS, revealing that both EV subtypes had unique proteomic characteristics. Multivalidation steps identified FRα, Claudin-3, and TACSTD2 as HGSOC-specific sEV proteins, but m/lEV-associated candidates were not identified. In addition, for using a simple-to-use microfluidic device for EV isolation, polyketone-coated nanowires (pNWs) were developed, which efficiently purify sEVs from biofluids. Multiplexed array assays of sEVs isolated by pNW showed specific detectability in cancer patients and predicted clinical status. In summary, the HGSOC-specific marker detection by pNW are a promising platform as clinical biomarkers, and these insights provide detailed proteomic aspects of diverse EVs in HGSOC patients.

Determination of the critical chain length for macromolecular crystallization using structurally flexible polyketones.

Critical chain length that divides small molecule crystallization from macromolecular crystallization is an important index in macro-organic chemistry to predict chain-length dependent properties of oligomers and polymers. However, extensive research on crystallization behavior of individual oligomers has been inhibited by difficulties in their synthesis and crystallization. Here, we report on the determination of critical chain length of macromolecular crystallization for structurally flexible polyketones consisting of 3,3-dimethylpentane-2,4-dione. Discrete polyketone oligomers were synthesized via stepwise elongation up to 20-mer. Powder and single crystal X-ray diffraction showed that the critical chain length for polyketones existed at an unexpectedly short chain length, 5-mer. While shorter oligomers adopted unique conformations and packing structures in the solid state, higher oligomers longer than 4-mer produced helical conformations and similar crystal packing. The critical chain length helped with understanding the inexplicable changes in melting point in the shorter chain length region resulting from chain conformations and packing styles.

Carbonyl-Containing Solid Polymer Electrolyte Host Materials: Conduction and Coordination in Polyketone, Polyester, and Polycarbonate Systems.

Research on solid polymer electrolytes (SPEs) is now moving beyond the realm of polyethers that have dominated the field for several decades. A promising alternative group of candidates for SPE host materials is carbonyl-containing polymers. In this work, SPE properties of three different types of carbonyl-coordinating polymers are compared: polycarbonates, polyesters, and polyketones. The investigated polymers were chosen to be as structurally similar as possible, with only the functional group being different, thereby giving direct insights into the role of the noncoordinating main-chain oxygens. As revealed by experimental measurements as well as molecular dynamics simulations, the polyketone possesses the lowest glass transition temperature, but the ion transport is limited by a high degree of crystallinity. The polycarbonate, on the other hand, displays a relatively low coordination strength but is instead limited by its low molecular flexibility. The polyester performs generally as an intermediate between the other two, which is reasonable when considering its structural relation to the alternatives. This work demonstrates that local changes in the coordinating environment of carbonyl-containing polymers can have a large effect on the overall ion conduction, thereby also showing that desired transport properties can be achieved by fine-tuning the polymer chemistry of carbonyl-containing systems.

Supramolecular Conformational Control of Aliphatic Oligoketones by Rotaxane Formation.

Conformational control of aliphatic oligoketones bearing two 1,3-diketone subunits is achieved by molecular recognition with pillar[5]arene. Pillar[5]arene binds to aliphatic ketones, with association constants K of ∼10 M-1, to form pseudorotaxanes. The pseudorotaxanes are locked by BF2 complexation at the 1,3-diketone sites through quasi-solid-state reactions. X-ray crystallography reveals linear conformations for the axis molecules. The effect of supramolecular conformational restriction is evaluated using an alkyl-linked dyad chromophore system that shows solvatochromism upon intramolecular aggregation.

Luminescent Coordination Polymers Constructed from a Flexible, Tetradentate Diisopyrazole Ligand and Copper(I) Halides.

One- and two-dimensional coordination polymers composed of a structurally flexible, tetradentate diisopyrazole ligand and copper(I) halides were synthesized as crystalline solids. Complexation with copper(I) chloride or bromide resulted in the formation of infinite coordination chains through connecting each diisopyrazole ligand with two copper(I) ions in a trigonal planar coordination geometry. Contrarily, the combination of a diisopyrazole ligand and copper(I) iodide gave a two-dimensional coordination network comprising Cu4 I4 units with stair-step type geometry and diisopyrazoles that acted as both tetradentate and bidentate bridging ligands. All the coordination polymers exhibited visible photo-emission upon UV irradiation, and the Cu4 I4 complex showed thermochromic behavior.

Two-Step Transformation of Aliphatic Polyketones into π-Conjugated Polyimines.

The chemo- and stereo-selective two-step transformation of aliphatic polyketones composed of 3,3-dimethylpentane-2,4-dione units was achieved to generate π-conjugated polyimines. Upon treatment with hydrazine, discrete oligoketones with 4-8 carbonyl groups afforded ethylene-bridged oligoisopyrazoles in 80-89% yields. These oligoisopyrazoles underwent stereoselective oxidation at the ethylene bridge to give fully π-conjugated oligo(isopyrazole-3,5-diyl-trans-vinylene)s in 73-87% yields. Oxidation of the oligoimines drastically changed their absorption and metal-coordination behaviors. Finally, this two-step transformation was applied to polydisperse polymers. Imine formation proceeded almost quantitatively, even for longer polyketones, including docosamer. Subsequent oxidation of the polyimines furnished a virtually insoluble material that showed broad and red-shifted solid-state absorption over the whole visible region resulting from extended π-conjugation.

Control over coordination self-assembly of flexible, multidentate ligands by stepwise metal coordination of isopyrazole subunits.

Structurally flexible oligoisopyrazole molecules were self-assembled into discrete complexes with structural diversity upon palladium coordination. Structural convergence was controlled by a stoichiometry change to induce stepwise metal coordination of isopyrazole subunits. Three different types of complexes were selectively generated from a diisopyrazole ligand. Furthermore, tetraisopyrazole ligands were quantitatively assembled into a discrete complex in a predictable manner.