Oligoethylene-Glycol-Functionalized Polyoxythiophenes for Cell Engineering: Syntheses, Characterizations, and Cell Compatibilities

A series of methyl- or benzyl-capped oligoethylene glycol functionalized 2,5-dibromo-3-oxythiophenes are synthesized and successfully polymerized by either Grignard metathesis (GRIM) polymerization or reductive coupling polymerization to yield the corresponding polymers in reasonable yields and molecular weights with narrow molecular weight distribution. These synthesized polyoxythiophenes exhibit high electroactivity and stability in aqueous solution when a potential is applied. Polyoxythiophenes from different polymerization approaches display different colors after purification and spectroelectrochemical studies confirm that the difference of color is from the difference of doping state. Little cytotoxicity is observed for the polymers by in vitro cell compatibility assay. NIH3T3 fibroblast cells are well attached and proliferate on spin-coated films. These results indicate that oligoethylene-glycol-functionalized polyoxythiophenes are promising candidates as conducting biomatierals for biomedical and bioengineering applications

Polydioxythiophene Nanodots, Nonowires, Nano-Networks, and Tubular Structures: The Effect of Functional Groups and Temperature in Template-Free Electropolymerization

Various nanostructures, including nanofibers, nanodots, nanonetwork, and nano- to microsize tubes of functionalized poly(3,4-ethylenedioxythiophene) (EDOT) and poly(3,4-propylenedioxythiophene) (ProDOT) are created by using a template-free electropolymerization method on indium–tin–oxide substrates. By investigating conducting polymer nanostructures containing various functional groups prepared at different polymerization temperature, we conclude a synergistic effect of functional groups and temperature on the formation of polymer nanostructures when a template-free electropolymerization method is applied. For unfunctionalized EDOT and ProDOT, or EDOT containing alkyl functional groups, nanofibers and nanoporous structures are usually found. Interesting, when polar functional groups are attached, conducting polymers tend to form nanodots at room temperature while grow tubular structures at low temperature. The relationship between surface properties and their nanostructures is evaluated by contact angle measurements. The capacity and electrochemical impedance spectroscopy measurements were conducted to understand the electrical properties of using these materials as electrodes. The results provide the relationship between the functional groups, nanostructures, and electrical properties. We also discuss the potential restriction of using this method to create nanostructures. The copolymerization of different functionalized EDOTs may cause irregular and unexpected nanostructures, which indicates the complex interaction between different functionalized monomers during the electropolymerization

Step-Economical Syntheses of Functional BODIPY-EDOT π‑Conjugated Materials through Direct C–H Arylation

Palladium-catalyzed direct C–H arylations of 4,4-difluoro-4-bora-3a,4a-diaza-<i>s</i>-indacene (BODIPY) with 3,4-ethylene­dioxythio­phene (EDOT) derivatives at relatively low temperature (60 °C) provide moderate to good yields (47%–72%) of products having potential applications in fluorescent bioimaging and organic optoelectronics

Controlled Protein Absorption and Cell Adhesion on Polymer-Brush-Grafted Poly(3,4-ethylenedioxythiophene) Films

Tailoring the surface of biometallic implants with protein-resistant polymer brushes represents an efficient approach to improve the biocompability and mechanical compliance with soft human tissues. A general approach utilizing electropolymerization to form initiating group (-Br) containing poly­(3,4-ethylenedioxythiophen)­s (poly­(EDOT)­s) is described. After the conducting polymer is deposited, neutral poly­((oligo­(ethylene glycol) methacrylate), poly­(OEGMA), and zwitterionic poly­([2-(methacryloyloxy)­ethyl]­dimethyl-(3-sulfopropyl)­ammonium hydroxide), poly­(SBMA), brushes are grafted by surface-initiated atom transfer radical polymerization. Quartz crystal microbalance (QCM) experiments confirm protein resistance of poly­(OEGMA) and poly­(SBMA)-grafted poly­(EDOT)­s. The protein binding properties of the surface are modulated by the density of polymer brushes, which is controlled by the feed content of initiator-containing monomer (EDOT-Br) in the monomer mixture solution for electropolymerization. Furthermore, these polymer-grafted poly­(EDOT)­s also prevent cells to adhere on the surface

Porous Structure of Polymer Films Optimized by Rationally Tuning Phase Separation for Passive All-Day Radiative Cooling

Passive all-day radiative cooling (PARC) films with porous structures prepared via nonsolvent-induced phase separation (NIPS) have attracted considerable attention owing to their cost-effectiveness and wide applicability. The PARC performances of the films correlate with their porous structures. However, the porous structure formed using the NIPS process cannot be finely regulated. In this study, we prepared polyvinylidene fluoride–hexafluoropropylene (PVDF–HFP) films with porous structures optimized by rationally tuning the phase separation, which was achieved by adjusting the proportions of two good solvents with varying solubility parameters. The optimized PVDF–HFP film with a hierarchically porous structure exhibited a high solar reflectance of 97.7% and an infrared emissivity of 96.7%. The film with excellent durability achieved an average subambient cooling temperature of approximately 5.4 °C under a solar irradiance of 945 W·m–2 as well as a temperature of 11.2 °C at nighttime, thus demonstrating all-day radiative cooling. The results indicate that the proposed films present a promising platform for large-scale applications in green building cooling and achieving carbon neutrality

Facile Syntheses of Dioxythiophene-Based Conjugated Polymers by Direct C–H Arylation

Various substituted dioxythiophenes bearing 3,4-propylenedioxythiophenes (ProDOT) and 3,4-ethylenedioxythiophene (EDOT) moieties successfully undergo Pd-catalyzed direct C–H arylation to yield π-conjugated polymers. The effects of palladium catalysts, phosphine ligands or additives, and functional groups on this facile polycondensation approach are investigated. Polymers from alkoxy-substituted ProDOT are synthesized with reasonable molecular weight (<i>M</i>_n = 6100–9600) and low PDI (1.3–1.9). Four substituted EDOT with alkoxy or protected functional groups also undergo direct C–H arylation polycondensation to yield corresponding polymers. The obtained polydioxythiophenes exhibit UV–vis absorptions ranging from 480 to 590 nm, and these conjugated polymers are electroactive and reversibly switched between the oxidized and neutral states upon applying potentials

Porous Structure of Polymer Films Optimized by Rationally Tuning Phase Separation for Passive All-Day Radiative Cooling

Passive all-day radiative cooling (PARC) films with porous structures prepared via nonsolvent-induced phase separation (NIPS) have attracted considerable attention owing to their cost-effectiveness and wide applicability. The PARC performances of the films correlate with their porous structures. However, the porous structure formed using the NIPS process cannot be finely regulated. In this study, we prepared polyvinylidene fluoride–hexafluoropropylene (PVDF–HFP) films with porous structures optimized by rationally tuning the phase separation, which was achieved by adjusting the proportions of two good solvents with varying solubility parameters. The optimized PVDF–HFP film with a hierarchically porous structure exhibited a high solar reflectance of 97.7% and an infrared emissivity of 96.7%. The film with excellent durability achieved an average subambient cooling temperature of approximately 5.4 °C under a solar irradiance of 945 W·m–2 as well as a temperature of 11.2 °C at nighttime, thus demonstrating all-day radiative cooling. The results indicate that the proposed films present a promising platform for large-scale applications in green building cooling and achieving carbon neutrality

Autophagy regulates spermatid differentiation via degradation of PDLIM1

<p>Spermiogenesis is a complex and highly ordered spermatid differentiation process that requires reorganization of cellular structures. We have previously found that <i>Atg7</i> is required for acrosome biogenesis. Here, we show that autophagy regulates the round and elongating spermatids. Specifically, we found that <i>Atg7</i> is required for spermatozoa flagella biogenesis and cytoplasm removal during spermiogenesis. Spermatozoa motility of <i>atg7</i>-null mice dropped significantly with some extra-cytoplasm retained on the mature sperm head. These defects are associated with an impairment of the cytoskeleton organization. Functional screening revealed that the negative cytoskeleton organization regulator, PDLIM1 (PDZ and LIM domain 1 [elfin]), needs to be degraded by the autophagy-lysosome-dependent pathway to facilitate the proper organization of the cytoskeleton. Our results thus provide a novel mechanism showing that autophagy regulates cytoskeleton organization mainly via degradation of PDLIM1 to facilitate the differentiation of spermatids.</p

Autophagy is required for ectoplasmic specialization assembly in sertoli cells

<p>The ectoplasmic specialization (ES) is essential for Sertoli-germ cell communication to support all phases of germ cell development and maturity. Its formation and remodeling requires rapid reorganization of the cytoskeleton. However, the molecular mechanism underlying the regulation of ES assembly is still largely unknown. Here, we show that Sertoli cell-specific disruption of autophagy influenced male mouse fertility due to the resulting disorganized seminiferous tubules and spermatozoa with malformed heads. In autophagy-deficient mouse testes, cytoskeleton structures were disordered and ES assembly was disrupted. The disorganization of the cytoskeleton structures might be caused by the accumulation of a negative cytoskeleton organization regulator, PDLIM1, and these defects could be partially rescued by <i>Pdlim1</i> knockdown in autophagy-deficient Sertoli cells. Altogether, our works reveal that the degradation of PDLIM1 by autophagy in Sertoli cells is important for the proper assembly of the ES, and these findings define a novel role for autophagy in Sertoli cell-germ cell communication.</p

Programming Thermoresponsiveness of NanoVelcro Substrates Enables Effective Purification of Circulating Tumor Cells in Lung Cancer Patients

Unlike tumor biopsies that can be constrained by problems such as sampling bias, circulating tumor cells (CTCs) are regarded as the “liquid biopsy” of the tumor, providing convenient access to all disease sites, including primary tumor and fatal metastases. Although enumerating CTCs is of prognostic significance in solid tumors, it is conceivable that performing molecular and functional analyses on CTCs will reveal much significant insight into tumor biology to guide proper therapeutic intervention. We developed the Thermoresponsive NanoVelcro CTC purification system that can be digitally programmed to achieve an optimal performance for purifying CTCs from non-small cell lung cancer (NSCLC) patients. The performance of this unique CTC purification system was optimized by systematically modulating surface chemistry, flow rates, and heating/cooling cycles. By applying a physiologically endurable stimulation (<i>i.e.</i>, temperature between 4 and 37 °C), the mild operational parameters allow minimum disruption to CTCs’ viability and molecular integrity. Subsequently, we were able to successfully demonstrate culture expansion and mutational analysis of the CTCs purified by this CTC purification system. Most excitingly, we adopted the combined use of the Thermoresponsive NanoVelcro system with downstream mutational analysis to monitor the disease evolution of an index NSCLC patient, highlighting its translational value in managing NSCLC