Mediated Electron Transport Research Articles

Strong Electron Coupling Effect of Prussian Blue Analogs Derived Ultrathin Nitrogen‐Doped Carbon Wrapped Fe‐CoP for Enhanced Wide Spectrum Photocatalytic H2 Evolution

AbstractWith the advantages of large specific surface area and high porosity of general metal‐organic frame materials, russian blue analogs have broad application prospects in catalysis. In this work, a series of ultra‐thin N‐doped carbon coated Fe‐CoP (Fe‐CoP@NC) are prepared by phosphating Fe‐Co‐Co Prussian blue analogs (Fe‐Co‐Co PBA) in different degrees for the broad‐spectrum photocatalytic hydrogen evolution. The results show that Fe‐CoP@NC‐3 has the highest photocatalytic hydrogen production rate of 16.6 mmol h−1 g−1, which is 83 times greater than that of Fe‐Co‐Co PBA. The excellent stability of Fe‐CoP@NC‐3 is proved by cyclic experiments. The outstanding photocatalytic H2 production activity of Fe‐CoP@NC‐3 can be ascribed to the strong electron coupling effect between Fe‐CoP and N‐doped carbon layer. The photogenerated electrons of Fe‐CoP are transferred to the N‐doped carbon layer, which is electron transport mediator accelerating the electron transfer and synergetic improving the hydrogen evolution efficiency. This work provides an effective strategy for designing an ultra‐thin N‐doped carbon layer coated phosphide photocatalyst with strong electron coupling effect.

Enhancement of peroxymonosulfate activation with nickel foam-supported CuCo2O4 for tetracycline degradation: Performance and mechanism insights

The modulation of bimetallic oxide structures and development of efficient, easily recoverable catalysts are expected to effectively overcome the limitations associated with powdered catalysts in activating peroxymonosulfate (PMS). In this study, CuCo2O4 was successfully immobilized on the surface of nickel foam (NF) via an electrodeposition-calcination procedure, with highly efficient activation of PMS for tetracycline (TC) degradation (0.55 min−1). Besides acting as a support carrier and providing ample active sites, NF mediated electron transport, prevented the leaching of metal ions and enhanced the efficiency of recycling. Density functional theory (DFT) calculations and experimental tests illustrated that Cu/Co dual-sites can efficiently adsorb PMS, enabling simultaneous reduction and oxidation reactions. The dual-site synergy substantially decreased the adsorption barrier and increased the electron transfer rate. Especially, the Cu+/Cu2+ redox couple acted as an electron donor and facilitated rapid charge transfer, leading to the conversion of Co3+ to Co2+. Moreover, the CuCo2O4@NF + PMS system effectively eliminated TC by employing radical pathways (SO4•−, •OH) and nonradical processes (1O2, e−). Therefore, this study introduces a new approach to overcome the limitations of powdered bimetallic oxides, providing a promising solution for practical applications.

Hydrogen Bonds and In situ Photoinduced Metallic Bi0/Ni0 Accelerating Z-Scheme Charge Transfer of BiOBr@NiFe-LDH for Highly Efficient Photocatalysis.

For heterojunction system, the lack of stable interfacial driving force and definite charge transfer channel makes the charge separation and transfer efficiency unsatisfactory. The photoreaction mechanism occurring at the interface also receives less attention. Herein, a 2D/2D Z-scheme junction BiOBr@NiFe-LDH with large-area contact featured by short interface hydrogen bonds and strong interfacial electric field (IEF) is synthesized, and in situ photoinduced metallic species assisting charge transfer mechanism is demonstrated. The hydrogen bonds between O atoms from BiOBr and H atoms from NiFe-LDH induce a significant interfacial charge redistribution, establishing a robust IEF. Notably, during photocatalytic reaction, Bi0 and Ni0 are in situ performed in heterojunction, which separately act as electron transport mediator and electron trap to further accelerate charge transfer efficiency up to 71.2 %. Theoretical calculations further demonstrate that the existence of Bi0 strengthens the IEF. Therefore, high-speed spatial charge separation is realized in Bi0/BiOBr@Ni0/NiFe-LDH, leading to a prominent photocatalytic activity with a tetracycline removal ratio of 88.3 % within 7 min under visible-light irradiation and the presence of persulfate, far exceeding majority of photocatalysts reported previously. This study provides valid insights for designing hydrogen bonding heterojunction systems, and advances mechanistic understanding on in situ photoreaction at interfaces.

Hydrogen Bonds and In situ Photoinduced Metallic Bi0/Ni0 Accelerating Z‐Scheme Charge Transfer of BiOBr@NiFe‐LDH for Highly Efficient Photocatalysis

AbstractFor heterojunction system, the lack of stable interfacial driving force and definite charge transfer channel makes the charge separation and transfer efficiency unsatisfactory. The photoreaction mechanism occurring at the interface also receives less attention. Herein, a 2D/2D Z‐scheme junction BiOBr@NiFe‐LDH with large‐area contact featured by short interface hydrogen bonds and strong interfacial electric field (IEF) is synthesized, and in situ photoinduced metallic species assisting charge transfer mechanism is demonstrated. The hydrogen bonds between O atoms from BiOBr and H atoms from NiFe‐LDH induce a significant interfacial charge redistribution, establishing a robust IEF. Notably, during photocatalytic reaction, Bi0 and Ni0 are in situ performed in heterojunction, which separately act as electron transport mediator and electron trap to further accelerate charge transfer efficiency up to 71.2 %. Theoretical calculations further demonstrate that the existence of Bi0 strengthens the IEF. Therefore, high‐speed spatial charge separation is realized in Bi0/BiOBr@Ni0/NiFe‐LDH, leading to a prominent photocatalytic activity with a tetracycline removal ratio of 88.3 % within 7 min under visible‐light irradiation and the presence of persulfate, far exceeding majority of photocatalysts reported previously. This study provides valid insights for designing hydrogen bonding heterojunction systems, and advances mechanistic understanding on in situ photoreaction at interfaces.

Insights into the role of electrochemical stimulation on sulfur-driven biodegradation of antibiotics in wastewater treatment

The presence of antibiotics in wastewater poses significant threat to our ecosystems and health. Traditional biological wastewater treatment technologies have several limitations in treating antibiotic-contaminated wastewaters, such as low removal efficiency and poor process resilience. Here, a novel electrochemical-coupled sulfur-mediated biological system was developed for treating wastewater co-contaminated with several antibiotics (e.g., ciprofloxacin (CIP), sulfamethoxazole (SMX), chloramphenicol (CAP)). Superior removal of CIP, SMX, and CAP with efficiencies ranging from 40.6 ± 2.6 % to 98.4 ± 1.6 % was achieved at high concentrations of 1000 μg/L in the electrochemical-coupled sulfur-mediated biological system, whereas the efficiencies ranged from 30.4 ± 2.3 % to 98.2 ± 1.4 % in the control system (without electrochemical stimulation). The biodegradation rates of CIP, SMX, and CAP increased by 1.5∼1.9-folds under electrochemical stimulation compared to the control. The insights into the role of electrochemical stimulation for multiple antibiotics biodegradation enhancement was elucidated through a combination of metagenomic and electrochemical analyses. Results showed that sustained electrochemical stimulation significantly enriched the sulfate-reducing and electroactive bacteria (e.g., Desulfobulbus, Longilinea, and Lentimicrobiumin on biocathode and Geobactor on bioanode), and boosted the secretion of electron transport mediators (e.g., cytochrome c and extracellular polymeric substances), which facilitated the microbial extracellular electron transfer processes and subsequent antibiotics removal in the sulfur-mediated biological system. Furthermore, under electrochemical stimulation, functional genes associated with sulfur and carbon metabolism and electron transfer were more abundant, and the microbial metabolic processes were enhanced, contributing to antibiotics biodegradation. Our study for the first time demonstrated that the synergistic effects of electrochemical-coupled sulfur-mediated biological system was capable of overcoming the limitations of conventional biological treatment processes. This study shed light on the mechanism of enhanced antibiotics biodegradation via electrochemical stimulation, which could be employed in sulfur-mediated bioprocess for treating antibiotic-contaminated wastewaters.

Resolving the Relaxation of Volatile Valence Change Memory

AbstractMemristive devices based on the valence change mechanism are highly interesting candidates for data storage and hardware implementation of synapses in neuromorphic circuits. Although long‐term retention is often required for data storage applications, a slight resistance drift of the low resistive state (LRS) is observed even for stable devices. For other devices, the LRS has been observed to decay rapidly to the high resistive state (HRS). These types of devices are of interest for neuromorphic circuits where short‐term plasticity is required. In this work, the LRS relaxation of volatile, crystalline Pt/SrTiO3/Nb:SrTiO3: devices is investigated in detail, yielding time constants ranging from milliseconds to seconds. The decay is analyzed in terms of the Gibbs free energy gradient for the contribution of oxygen ion migration. A relaxation model based on drift‐diffusion dynamics is presented. The model may serve as a tool for developing guidelines and design rules for future volatile memristive technology based on Schottky barrier mediated electron transport.

Chemically Mediated Artificial Electron Transport Chain.

Electron transport chains (ETCs) are ubiquitous in nearly all living systems. Replicating the complexity and control inherent in these multicomponent systems using ensembles of small molecules opens up promising avenues for molecular therapeutics, catalyst design, and the development of innovative energy conversion and storage systems. Here, we present a noncovalent, multistep artificial electron transport chains comprising cyclo[8]pyrrole (1), a meso-aryl hexaphyrin(1.0.1.0.1.0) (naphthorosarin 2), and the small molecules I2 and trifluoroacetic acid (TFA). Specifically, we show that 1) electron transfer occurs from 1 to give I3 - upon the addition of I2, 2) proton-coupled electron transfer (PCET) from 1 to give H 3 2 •2+ and H 3 2 + upon the addition of TFA to a dichloromethane mixture of 1 and 2, and 3) that further, stepwise treatment of 1 and 2 with I2 and TFA promotes electron transport from 1 to give first I3 - and then H 3 2 •2+ and H 3 2 + . The present findings are substantiated through UV-vis-NIR, 1H NMR, electron paramagnetic resonance (EPR) spectroscopic analyses, cyclic voltammetry studies, and DFT calculations. Single-crystal structure analyses were used to characterize compounds in varying redox states.

First polyoxometalate-modified SnS2 composite nanostructure gas sensor toward enhanced sensitivity and high selectivity for NO2 detection

In this work, the first polyoxometalate modified SnS2 gas sensor are synthesized by convenient hydrothermal method and applied for detecting NO2 gas in the air. Under optimal test condition, the SnS2-3%PW12 sensor delivered a gas sensing response of 3.9 to 50 ppm NO2 gas, which is 2.3 times higher than pure SnS2 sensor. Fast response/recovery time (24/30 s) and low limit-of-detection (53 ppb) were also exhibited. Repeatability, long-term stability and humidity resistance were both good. The mechanism analysis shows that PW12, as an electron-transport mediator, can trap electrons in the conduction band of SnS2, generate shallow electron traps, and effectively inhibit the recombination of electrons and holes in SnS2, thereby enhancing gas sensing performance for NO2 detection. This paper introduces a new way of developing high sensitivity SnS2-based gas sensors by introducing polyoxometalates as electron acceptors.

Bioinspired photoelectrochemical NADH regeneration based on a molecular catalyst-modified photocathode.

For photoelectrochemical NADH regeneration, an electrode-supported "lipid bilayer membrane" photocathode based on a p-Si semiconductor, an electron transport mediator (OBV2+), and a [Rh(Cp*)(bpy)Cl]+ catalyst was constructed by self-assembly. Mechanistic study shows that OBV2+ can enhance the charge transfer between the semiconductor and catalyst, leading to a significant improvement of the NADH photo-regeneration rate.

Tools to Simulate Resonance Raman Spectra for in-Situ Studies of Electron Transport Mediators and Bioelectrocatalysts

Raman spectroscopy is widely applied as an in-situ probe of electrochemical processes. When the excitation light is resonant with an electronic transition, the detected signal can be enhanced by more than 1,000-fold. Resonance Raman (RR) spectroscopy has broad application in the study of common organic electron transport mediators (i.e., viologens, phenazines, photosynthetic pigments) and active sites of redox proteins (i.e., laccases, peroxidases, flavin-containing enzymes). To support investigations of bioelectrocatalytic membranes, we have been adapting RR spectroscopy to gain insights into the properties of immobilized redox mediators and biocatalyst active sites.1,2 Computational methods can be useful for guiding spectral interpretation. This poster reports on applications of recently advanced time-dependent density functional theory (TDDFT) codes that enable the simulation of RR spectra for small electron transport mediators (e.g., methyl viologen radical anion) and redox protein active site models (e.g., laccase T1 site mimics). The ORCA program suite3 was adapted. A series of Cu-centered compounds that model the T1 active site in laccases was studied along with the methyl viologen radical cation. The T1 site in laccases facilitates direct electron transport to an electrode and is a target for in-situ RR measurements. The reported work demonstrates careful selection of the functional (B3-LYP versus the long-range corrected hybrid exchange functional, ωB97X-D3) results in TDDFT-calculated electronic absorption and RR spectra that have features in excellent agreement with experiment. The results provide a foundation to build from in advancing models of small redox mediators and laccase catalytic active sites in support of sustainable technologies. Ozuguzel, U.; Aquino, A.J.A.; Nieman, R.; Minteer, S.D.; Korzeniewski, C. “Calculation of Resonance Raman Spectra and Excited State Properties for Blue Copper Protein Model Complexes” ACS Sustainable Chem. Eng. 2022, 10, 14614. Xu, J.; Koh, M.; Minteer, S. D.; Korzeniewski, C. “In Situ Confocal Raman Microscopy of Redox Polymer Films on Bulk Electrode Supports” ACS Measurement Science Au 2023 (DOI: 10.1021/acsmeasuresciau.2c00064). Neese, F.; Wennmohs, F.; Becker, U.; Riplinger, C. “ORCA Quantum Chemistry Program Package” J. Chem. Phys. 2020, 152, 224108.

A construction of core–shell dual zeolite imidazole skeleton derived composite to facilitate photocarrier separation and distribution of active sites for photocatalytic water oxidation

Limited by the severe carrier recombination and insufficient active sites of the catalyst, achieving efficient photocatalytic water oxidation remains a major challenge. Herein, a core–shell zeolite imidazole skeleton (ZIF) based material with rich active sites in its interior is obtained by in-situ growth carbonization two steps method. According to characterization, performance testing and photoelectric experiments, it is confirmed that the ZIF67@ZIF8-2-800 material has good photogenerated carrier separation efficiency and surprising O2 production. The reason for the performance improved is that ZIF8 as a shell prevents the agglomeration of active sites CoO in the carbonization process of ZIF67. Theoretical calculations reveal that the core–shell structure has a favorable influence on the separation of photogenerated carriers. The N atom acts as an electron transport mediator, transferring electrons from the CoO core to the NC shell, while the holes remain in the CoO to participate in the photocatalytic water oxidation reaction.

Pyrolyzed sediment accelerates electron transfer and regulates rhodamine B biodegradation

Electron transfer efficiency is a key factor that determined the removal of environmental pollution through biodegradation. Electron shuttles exogenously addition is one of the measures to improve the electron transfer efficiency. In this study, the sediment was pyrolyzed at different temperature to investigate its properties of mediating electron transfer and removing of rhodamine B (RhB) in microbial electrochemical systems (MESs). Sediments pyrolyzed at 300 °C (PS300) and 600 °C (PS600) have promoted electron transfer which led to 16 % enhancement of power generation while the result is reversed at 900 °C (PS900). Although power output of PS300 and PS600 are similar, the removal efficiency of RhB is not consistent, which may be caused by the biofilm structure difference. Microbial community analysis revealed that the abundance of EAB and toxicity-degrading bacteria (TDB) in PS600 was 6 % higher than that in PS300. The differentiation of microbial community also affected the metabolic pathway, the amino synthesis and tricarboxylic acid cycle were primarily upregulated with PS600 addition, which enhanced the intracellular metabolism. However, a more active cellular anabolism occurred with PS300, which may have been triggered by RhB toxicity. This study showed that pyrolytic sediment exhibits an excellent ability to mediate electron transport and promote pollutant removal at 600 °C, which provides a techno-economically feasible scenario for the utilization of low-carbon-containing solid wastes.

Resonance Raman spectra and excited state properties of methyl viologen and its radical cation from time-dependent density functional theory.

Time-dependent density functional theory (TDDFT) was applied to gain insights into the electronic and vibrational spectroscopic properties of an important electron transport mediator, methyl viologen (MV2+ ). An organic dication, MV2+ has numerous applications in electrochemistry that include energy conversion and storage, environmental remediation, and chemical sensing and electrosynthesis. MV2+ is easily reduced by a single electron transfer to form a radical cation species (MV•+ ), which has an intense UV-visible absorption near 600 nm. The redox properties of the MV2+ /MV•+ couple and light-sensitivity of MV•+ have made the system appealing for photo-electrochemical energy conversion (e.g., solar hydrogen generation from water) and the study of photo-induced charge transfer processes through electronic absorption and resonance Raman spectroscopic measurements. The reported work applies leading TDDFT approaches to investigate the electronic and vibrational spectroscopic properties of MV2+ and MV•+ . Using a conventional hybrid exchange functional (B3-LYP) and a long-range corrected hybrid exchange functional (ωB97X-D3), including with a conductor-like polarizable continuum model to account for solvation, the electronic absorption and resonance Raman spectra predicted are in good agreement with experiment. Also analyzed are the charge transfer character and natural transition orbitals derived from the TDDFT vertical excitations calculated. The findings and models developed further the understanding of the electronic properties of viologens and related organic redox mediators important in renewable energy applications and serve as a reference for guiding the interpretation of electronic absorption and Raman spectra of the ions.

Interaction mediated electron transport within the many-body tunnelling Hamiltonian

For a non-superconducting system and in the spirit of the transfer or tunnelling Hamiltonian formalism, an expression for the electronic tunnelling current through an insulating barrier is calculated, explicitly taking into account the effects of electron-electron interactions that can persist across the barrier. In the presence of a single tunnelling barrier, the exact Hamiltonian is projected onto the subspaces of the ‘left’ and ‘right’ conducting leads. In the weak-tunnelling limit, the well-known tunnelling Hamiltonian is recovered, along with an additional term. This additional term originates from the projection of the electron-electron interaction onto each subspace and corresponds to a correlated or interaction-mediated tunnelling. It is shown that the tunnelling current in this approximation is related to—in addition to the single-particle density of states—the two-particle spin-spin and density-density susceptibilities. The signatures of these terms have been observed in scanning tunnelling microscope experiments on atomic spin chains.

Enhancing mediated electron transfer in for efficient chloramphenicol degradation through Cu-modified Co@C catalyst

The degradation of organic pollutants in wastewater, such as the veterinary antibiotic chloramphenicol (CAP), is commonly achieved by increasing the concentration of reactive oxygen species (ROS). However, the contribution of the mediated electron transfer pathway is often overlooked. To address this, a carbon-coated CuCo bimetallic catalyst (CuCo@C) is synthesized by adding Cu into Co@C to activate peroxymonosulfate (PMS) for efficient degradation of CAP. The CuCo@C/PMS system exhibits high degradation activity, relying on the presence of ROS pathway and the enhanced mediated electron transfer pathway. The latter is facilitated by the excellent electron transport ability of the Cu-added Co@C catalyst, which accepts electrons from the CAP to form the active CuCo@C/PMS* complex, allowing further decomposition of CAP. The strong synergy between these two pathways results in a rate constant of first-order reactions (Kobs) of 0.124 min−1, which is 2.2 and 22.9 times higher than those achieved by the single metal systems of Co@C/PMS and Cu@C/PMS, respectively. Intermediate products and toxicity analysis reveal that the toxicity of the CuCo@C/PMS system for the degradation of CAP is substantially reduced. Overall, this work offers a novel perspective on the efficient activation of PMS through enhancing mediated electron transport pathway.

Polyoxometalate-modified ternary copper-tungsten-sulfide nanocrystals as high-performance counter electrode materials for quantum dots-sensitized solar cells

The Cu2WS4/[Me2NH2]11[CeIII(PW11O39)2] (CWS/CeIII(PW11)2) composite is synthesized by simple solvothermal method and first applied as a counter electrode material in CdS/CdSe/ZnS-sensitized quantum dot sensitized solar cell (QDSSCs). Due to the co-existence of copper and tungsten in different valence states, the ternary CWS has more redox active sites than the binary Cu2S. Besides, the conduction band of CeIII(PW11)2 and CWS are well matched, so the electrons transport from CB of CeIII(PW11)2 to CWS is a favorable exothermic process. Brunauer-Emmett-Teller (BET), electrochemical impedance spectroscopy (EIS), Tafel-polarization test (Tafel), open-circuit voltage decay (OCVD) and cyclic voltammetry (CV) tests all confirmed that 4% CeIII(PW11)2/CWS (CWS-4) has the highest electrocatalytic activity. Under simulated sunlight, QDSSCs with CWS-4 CE delivered a power conversion efficiency (PCE) of 6.63% (Jsc = 23.42 mA cm−2, Voc = 0.62 V, FF = 0.46), which is 12% and 44% higher than QDSSCs with CWS and Cu2S CEs, respectively. CeIII(PW11)2, as an "electron-transport mediator" to compound with CWS can generate "shallow electron traps", increase active sites, and effectively inhibit the recombination of charges, thereby enhancing cell performance.

Abstract 10883: Cigarette Smoking and Mitochondrial Function in Peripheral Artery Disease

Introduction: In humans without peripheral artery disease (PAD) and animal models, exposure to cigarette smoke is associated with reduced mitochondrial respiratory function. Many people with PAD smoke cigarettes, but the association of smoking with mitochondrial function in lower extremity skeletal muscle of people with PAD is unknown. Methods: From the Chicago, IL area, 31 people with PAD (ankle brachial index (ABI) < 0.90) were enrolled and consented to gastrocnemius muscle biopsy. Mitochondrial oxidative capacity in gastrocnemius muscle was measured with respirometry. Western blots were performed to quantify mitochondrial membrane abundance via voltage-dependent anion channel (VDAC), mitochondrial biogenesis via peroxisome proliferator-activated receptor-γ coactivator (PGC-1α) , and electron transport chain complexes I-V. Results: Among 31 people with PAD (mean 72.1 years, mean ABI 0.64), 14 (45.2%) smoked cigarettes currently. Participants who currently smoked had higher abundance of PGC-1α (0.75 vs. 0.45 arbitrary units (AU), P<0.01), VDAC (0.62 vs. 0.37 AU, P=0.022), electron transport chain complex I (0.46 vs. 0.21 AU, P=0.031), and complex III (0.76 vs. 0.42 AU, P=0.031), compared to those who did not currently smoke. After normalizing to VDAC, participants who currently smoked had lower mitochondrial oxidative capacity per unit of mitochondrial membrane compared to those who did not currently smoke (complex I+II-mediated oxidative phosphorylation (156.3 vs. 287.0 AU, P=0.017), complex I+II-mediated electron transport chain capacity (184.8 vs. 343.1 AU, P=0.019), complex I-mediated fatty acid oxidative phosphorylation (45.9 vs. 82.1 AU, P=0.034)). After statistical adjustment for age, sex, race, ABI, and body mass index (BMI), most associations were attenuated but remained statistically significant for the higher abundance of VDAC (0.65 vs. 0.35 AU, P=0.037) and complex I (0.50 vs. 0.18 AU, P=0.038) in participants who currently smoked compared to those who did not currently smoke. Conclusions: Results suggest that among people with PAD, current cigarette smoking may stimulate a compensatory increase in mitochondrial biogenesis that may counteract effects of reduced oxidative capacity per unit mitochondrial membrane.

Abstract 12: Social isolation promotes mammary cancer recurrence, increases IL6/JAK/STAT3 signaling and causes mitochondrial dysfunction in tamoxifen treated rats, and a traditional herbal mixture reverses all these changes

Abstract Social isolation is associated with increased risk and mortality from many diseases, such as breast cancer. Socially isolated breast cancer survivors have a 43% higher risk of recurrence and a 64% higher risk of breast cancer-specific mortality than socially integrated survivors. Since Covid-19 has dramatically increased the incidence of social isolation, it is important to determine if social isolation affects the response to endocrine therapy and/or recurrence after the therapy is completed. Since previous studies indicate that social isolation increases circulating inflammatory cytokines, we investigated if an anti-inflammatory herbal mixture Jaeumkanghwa-tang (JGT) prevents the adverse effects of social isolation on breast cancer mortality. Estrogen receptor positive mammary tumors were initiated with 7,12-dimethylbenz[a]anthracene. When a rat developed a palpable mammary tumor, it was either socially isolated (SI) by housing it singly or a rat was allowed to remain group-housed (GH). Tamoxifen (340ppm via diet) or tamoxifen + JGT (500ppm via drinking water) started when the first mammary tumor reached a size of 11 mm in diameter. Tamoxifen administration ended when a complete response to this therapy had lasted for 9 weeks (corresponds to 5 years in women). During tamoxifen therapy, social isolation non-significantly reduced the rate of complete responses to 21%, from 31% in GH group (p>0.05). After the therapy was completed, SI significantly increased local mammary tumor recurrence (p<0.001; 45% GH vs 75% SI). RNAseq analysis was performed in the mammary glands. Gene set enrichment analysis (GSEA) of transcriptome showed that the increased recurrence risk in socially isolated rats was associated with an enrichment of IL6/JAK/STAT3 signaling: this result was confirmed in the tumors. In addition, oxidative phosphorylation (OXPHOS) pathway was suppressed: the suppressed genes included those involved in mitochondrial pyruvate transport and conversion of pyruvate to acetyl CoA as well as genes in the TCA cycle and mediating electron transport in mitochondrial complexes I-IV. Social isolation also increased the expression of inflammatory receptor for advanced glycation end-products (RAGE) (p≤0.05). Consumption of an anti-inflammatory JGT inhibited IL6/JAK/STAT3 signaling, upregulated OXPHOS signaling and prevented the increased risk of mammary cancer recurrence in socially isolated animals. The percentage of recurrences in the SI rats dropped from 75% without JGT to 22% with JGT (p<0.001). Breast cancer mortality among socially isolated survivors may be most effectively prevented by focusing on the period following endocrine therapy using tools that inhibit IL6/JAK/STAT3 inflammatory cytokine signaling and correct disrupted OXPHOS and mitochondrial dysfunction. Citation Format: Fabia de Oliveira Andrade, Lu Jin, Robert Clarke, Imani Wood, MaryAnn Dutton, Chezaray Anjorin, Grace Rubin, Audrey Gao, Surojeet Sengupta, Kevin FitzGerald, Leena Hilakivi-Clarke. Social isolation promotes mammary cancer recurrence, increases IL6/JAK/STAT3 signaling and causes mitochondrial dysfunction in tamoxifen treated rats, and a traditional herbal mixture reverses all these changes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 12.

NADPH Oxidase 4: A Potential Therapeutic Target of Malignancy.

Reactive oxygen species (ROS) play a crucial role in the regulation of tumor occurrence and development. As a main source of ROS, NADPH oxidases are key enzymes that mediate electron transport within intracellular membranes. Of the NOX members that have been reported to be dysregulated in a wide variety of tumors, NOX4 is the member to be most frequently expressed. Numerous studies have elucidated that NOX4 gets involved in the regulation of tumor proliferation, metastasis, therapy resistance, tumor-stromal interaction and dysregulated tumor metabolism. In this review, we primarily discussed the biological function of NOX4 in tumorigenesis and progression of multiple cancer models, including its role in activating oncogenic signaling pathways, rewiring the metabolic phenotype and mediating immune response. Besides, the development of NOX4 inhibitors has also been unraveled. Herein, we discussed the interplay between NOX4 and tumorigenesis, proposing NOX4 as a promising therapeutic target waiting for further exploration.

Synthesis of polymer-gel electrolytes for quasi solid-state dye-sensitized solar cells and Modules: A potential photovoltaic technology for powering internet of things (IoTs) applications

Dye-sensitized solar cells can display brilliant performance in artificial/indoor light, predominantly in various wireless sensor networks applications. The main objective of this work was to fabricate stable dye-sensitized solar cells/modules for the internet of things applications. The stability issue was addressed by developing polymer gel electrolytes. Polymer gel electrolyte with the highest ionic conductivity value was then employed as an electron transport mediator in the cells and modules. The photovoltaic performance of cells was affected by the conductivity of electrolytes. The results showed that the efficiency of quasi-solid state dye-sensitized solar cells remained stable for a week, while the efficiency of conventional cells approached zero after a day. Thus, the development of polymer gel electrolytes is an ultimate solution to enhance the stability of dye-sensitized solar cells and modules for the internet of things applications.