Organic Networks Research Articles

Construction of Porous Tetrazine‐Functionalized Networks: From Two‐ to Three‐Dimensional Counterparts with Tunable Properties

AbstractPorous organic networks (PONs) linked by aza‐fused rings are extensively studied and demonstrated wide applications in diverse fields. It is a long‐term attractive and challenging subject to explore novel PONs functionalized by unexplored aza‐fused moieties. Herein, a series of tetrazine‐linked PONs (Tz‐PONs) were constructed from two‐dimensional to three‐dimensional counterparts with tunable properties. The reaction pathway composed of the amidrazone intermediates formation using multiply substituted aromatic nitrile monomers was catalyzed by zinc salts with Lewis super acidity in the presence of hydrazine, and the subsequent tetrazine formation was assisted by sodium nitrite solution. Textural property of the as‐constructed scaffolds could be tuned by the acidity of the zinc salts, as well as the organic solvents. As an initial assessment, those Tz‐PONs displayed different photo absorption behavior, which may influence the corresponding photocatalysis.

Synthesis of a fluorophilic magnetic microporous organic network for selective enrichment of fipronil and ethiprole in milk and egg samples.

Considering the widespreadly use, large consumption, and serious environmental and health threats of phenylpyrazole insecticides (PPIs), development of a selective and sensitive method for accurate detection of their residuals in food samples is of great significance and challenging. Herein, depending on the hydrophobic and F-containing characteristics of PPIs, a novel fluorinated magnetic microporous organic network (FMMON) was designed and prepared for efficient and selective magnetic solid-phase extraction (MSPE) of two typical PPIs (fipronil and ethiprole) from milk and egg samples before the HPLC-UV determination. FMMON owned large specific surface area, multiple interaction sites, excellent magnetic separation performance and stability and exhibited good extraction and selectivity for fipronil and ethiprole through the specific F-F, hydrogen bonding, hydrophobic, and π-π interactions. Under optimal extraction conditions, the established FMMON-MSPE-HPLC-UV method provided wide linear ranges (0.1-1000 µg L-1), low limits of detection (0.03-0.05 µg L-1), large enrichment factors (96.2-99.7), low adsorbent consumption (4 mg), and short extraction time (6 min) for fipronil and ethiprole. This work revealed the bright future of fluorinated MONs in sample pretreatment of fluorinated contaminants in complex substrates.

Enhancement of adipose stem cell quality via Cu‐MON: Transcriptome and bioinformatics analysis of normal and diabetic stem cells

AbstractTransplanted adipose stem cells (ASC) have a low survival rate in the body, and there are not many ASC that can be effectively used, which weakens their tissue repair function. Based on this status quo, a new type of copper‐based metal–organic network (Cu‐MON) was used to pretreat cells to regulate cell activity in order to improve the efficacy of cell therapy or reduce the number of cells used, thus reducing the cost of clinical treatment. Gene expression changes before and after Cu‐MON treatment of normal donor adipose stem cells (ND‐ASC) and type 2 diabetes mellitus adipose stem cells (T2DM‐ASC) were evaluated through RNA sequencing, KEGG and GO enrichment analysis. The results showed that Cu‐MON improved ASC cell quality by regulating immune response and promoting paracrine secretion. IL‐17 signaling pathway and IL‐6, CXCL8, and MMP‐9 were key pathways and necessary genes that affected the ability of stem cells. In addition, Cu‐MON also improved stem cell antiviral ability through Type I interferon signaling pathway. Our research showed that Cu‐MON had improved the cell quality of ASC by regulating immune response, promoting paracrine secretion, and improving antiviral capabilities. This approach to biomaterial pretreatment is fast, convenient, and relatively safe, and provides new strategies for improving the efficiency of cell therapies.

Nanoscale and hollow inorganic sulfide@porous organic network doped intelligent hydrogels for accelerating diabetes wound therapeutics

Nanoscale and hollow inorganic sulfide@porous organic network doped intelligent hydrogels for accelerating diabetes wound therapeutics

Hydroxylated magnetic microporous organic network for efficient magnetic solid phase extraction of trace triazine herbicides.

Here we covalently constructed abundant long-chain hydroxyl groups-functionalized magnetic microporous organic networks (MMON-2OH) for detection of eight Triazine herbicides (THs) in honey and water samples. MMON-2OH owned a high surface area (287.86 m²/g), enhanced water compatibility, and increased exposure of long-chain hydroxyl groups, which significantly improved enrichment capacity for THs. Theoretical analyses and characterization data revealed interaction mechanisms, including hydrogen bonds (N-H···O and O-H···N), halogen bond (Cl···N) and π stackings (NH-π, CH-π and π-π). This approach was developed for the detection of THs, achieving a low detection limit 0.03∼0.6 ng⋅L-1 for water, and 0.006∼0.134 μg·kg-1 for honey. Trace concentrations of THs, ranging from 1.0∼21.2 ng⋅L-1 in surface water and 0.1∼0.9 μg·kg-1 in honey, were successfully detected. Sample spiked recovery experiments demonstrated recoveries between 72.1-116.2 %, validating accuracy and applicability of method. This study realizes a speedy and sensitive determination of THs, showcasing potential of MMON-2OH in pollutant removal and food safety maintenance.

Fabrication of microporous organic network incorporated monolithic column for improved high performance liquid chromatographic separation of small molecules

Fabrication of microporous organic network incorporated monolithic column for improved high performance liquid chromatographic separation of small molecules

Recent advances of magnetic microporous organic networks in magnetic solid phase extraction

Recent advances of magnetic microporous organic networks in magnetic solid phase extraction

Dual-Modal Memory Enabled by a Single Vertical N-Type Organic Artificial Synapse for Neuromorphic Computing.

Complementary neural network circuits combining multifunctional high-performance p-type with n-type organic artificial synapses satisfy sophisticated applications such as image cognition and prosthesis control. However, implementing the dual-modal memory features that are both volatile and nonvolatile in a synaptic transistor is challenging. Herein, for the first time, we propose a single vertical n-type organic synaptic transistor (VNOST) with a novel polymeric organic mixed ionic-electronic conductor as the core channel material to achieve dual-modal synaptic learning/memory behaviors at different operating current densities via the formation of an electric double layer and the reversible ion doping. As a volatile synaptic device, the resulting VNOST demonstrated an unprecedented operating current density of MA cm-2. Meanwhile, it is capable of 150 analog states, symmetric conductance modulation, and good state retention (100 s) for a nonvolatile synapse. Importantly, the artificial neural networks (ANNs) for recognition accuracy of the handwritten digital data sets recognition rate up to 94% based on its nonvolatile feature. This study provides a promising platform for building organic neuromorphic network circuits in complex application scenarios where high-performing n-type organic synapse transistors with dual-mode memory characters are necessitated.

Acceleration of Reaction Space Projector Analysis Using Combinatorial Optimization: Application to Organic Chemical Reactions.

In recent years, automated reaction path search methods have established the concept of a reaction route network. The Reaction Space Projector (ReSPer) visualizes the potential energy hypersurface into a lower-dimensional subspace using principal coordinates. The main time-consuming process in ReSPer is calculating the structural distance matrix, making it impractical for complex organic reaction route networks. We implemented the Alternate Optimization (AO) algorithm, one of the combinatorial optimizations, in ReSPer to reduce computational costs. Evaluations using gold clusters and the Au5 several reaction route networks showed that ReSPer-AO accurately computes distances with lower computational costs. Applying ReSPer-AO to the C5H8O reaction route network clarified dynamic conformation changes in its potential energy landscape. The ReSPer-AO method enables analysis of chemical reactions and dynamic conformations in a low-dimensional reaction space that accurately represents hydrocarbon reaction route networks.

Cellular and molecular characterization of peripheral glia in the lung and other organs.

Peripheral glia are important regulators of diverse physiologic functions yet their molecular distinctions and locations in almost all visceral organs are not well-understood. We performed a systematic analysis of peripheral glia, focusing on the lung and leveraging single cell RNA sequencing (scRNA-seq) analysis to characterize their cellular and molecular features. Using in vivo lineage studies, we characterized the anatomic, cellular, and molecular features of the Sox10+ glial lineage of the mouse lung. Using high-resolution imaging, we quantified the distribution and cellular morphologies of myelinating, non-myelinating, satellite, and terminal glial cells with their intricate extensions along peripheral nerves, including terminals at specialized neurosensory structures within the lung. Spatial analysis of selectively expressed myelinating (periaxin/Prx, claudin 19/Cldn) or non-myelinating (sodium channel/Scn7a) glial cell genes identified by scRNA-seq analysis revealed molecularly distinct populations surrounding myelinated nerve fibers in the lung. To extend this analysis to primates and other organs, we extracted rare peripheral glial cells in whole organism scRNA-seq atlases of mouse lemur and human. Our cross-species data analysis and integration of scRNA-seq data of ~700 peripheral glial cells from mouse, mouse lemur, and human glial cells identified conserved gene expression of molecularly distinct peripheral glial cell populations. This foundational knowledge facilitates subsequent functional studies targeting molecularly distinct subsets of peripheral glia and integrating them into organ-specific disorders of autonomic dysregulation. In addition, our cross-species analysis identifying conserved gene expression patterns and glial networks in extrapulmonary organs provides a valuable resource for studying the functional role of peripheral glia in multiorgan human diseases.

Electrocatalytic Water Splitting in Isoindigo-based Covalent Organic Frameworks.

Developing a low-cost, robust, and high-performance electrocatalyst capable of efficiently performing both the oxygen evolution reactionand the hydrogen evolution reaction (HER) under both basic and acidic conditions is a major challenge. This area of research has attracted much attention in recent decades due to its importance in energy storage and conversion. Herein, we report the synthesis of two imine-linked isoindigo-based covalent organic networks. The combination of isoindigo dialdehyde with a planar triazine core, leads to the formation of thin, highly crystalline, planar 2D-nanosheets covalent organic framework (I-TTA COF), whereas its combination with ionic non-planar guanidinium core leads to an amorphous covalent organic polymer (I-TG COP) with a fibrous morphology. The sheet-like crystalline I-TTA COF shows better electrocatalytic activity compared to the amorphous fibrous I-TG COP. I-TTA exhibits a current density of 10 mA cm-2 at an overpotential of ~134 mV for HER (in 0.5 M H2SO4) and ~283 mV for OER (in 1 M KOH). The electrocatalytic activity of the I-TTA COF in the OER exceeds that of other metal-free COFs. The catalytic activity is maintained even after 24 hours of chronoamperometry and 500 cycles of cyclic voltammetry (CV) at high scan rates.

Electrocatalytic Water Splitting in Isoindigo‐based Covalent Organic Frameworks

Developing a low‐cost, robust, and high‐performance electrocatalyst capable of efficiently performing both the oxygen evolution reaction and the hydrogen evolution reaction (HER) under both basic and acidic conditions is a major challenge. This area of research has attracted much attention in recent decades due to its importance in energy storage and conversion. Herein, we report the synthesis of two imine‐linked isoindigo‐based covalent organic networks. The combination of isoindigo dialdehyde with a planar triazine core, leads to the formation of thin, highly crystalline, planar 2D‐nanosheets covalent organic framework (I‐TTA COF), whereas its combination with ionic non‐planar guanidinium core leads to an amorphous covalent organic polymer (I‐TG COP) with a fibrous morphology. The sheet‐like crystalline I‐TTA COF shows better electrocatalytic activity compared to the amorphous fibrous I‐TG COP. I‐TTA exhibits a current density of 10 mA cm−2 at an overpotential of ~134 mV for HER (in 0.5 M H2SO4) and ~283 mV for OER (in 1 M KOH). The electrocatalytic activity of the I‐TTA COF in the OER exceeds that of other metal‐free COFs. The catalytic activity is maintained even after 24 hours of chronoamperometry and 500 cycles of cyclic voltammetry (CV) at high scan rates.

Thiol-yne click postsynthesis of imidazole-functionalized cyclodextrin microporous organic network: A remarkable adsorbent for sulfonamide antibiotics

Sulfonamides (SAs) are widely used broad-spectrum antibiotics for treating infections. However, their inevitable residues pose serious threats to human health and agroecosystems. Hence, reasonable design and synthesis efficient adsorbents to remove residual SAs from the environment are crucial and highly desired. In this study, a novel imidazole-functionalized cyclodextrin-based microporous organic network (α-CD-MON-BZ) was designed and synthesized through the specific thiol-yne click post-modification for the efficient removal of SAs. The prepared α-CD-MON-BZ exhibited ultrafast adsorption kinetics (<3 min) and an exceptionally high saturation adsorption capacity (571.4 mg/g) for sulfamethoxypyridazine (SMP). This capacity was much higher than those of other reported adsorbents. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculations revealed that the adsorption process involves hydrophobic, π–π, hydrogen bonding, host–guest, and electrostatic interactions. Furthermore, α-CD-MON-BZ exhibited favorable reusability and selectivity. This study introduces a new method to construct novel functionalized CD-MONs for highly efficient SAs removal and promotes the design and applications of such materials in contaminant removal.

Expanding a machine learning class towards its application to the stock market forecast

In this work, we present a new and efficient algorithm to perform a short-term market trend forecast, based on the Artificial Organic Networks (AON) metaheuristic machine learning framework. Regarding this goal, we present the concept of Artificial Halocarbon Compounds (AHC) or AHC-algorithm as a bio-inspired supervised machine learning algorithm based on the AON framework. Through our research, we contrast the forecast acquired with the proposed AHC model, to previously reported outcomes using the Artificial Hydrocarbon Networks (AHN) in similar tasks. The AHN algorithm is the first formally defined topology based on the AON, making the AHN algorithm a vital benchmark to contemplate. After comparing the AHC-algorithm to the original AHN-algorithm, we found out that due to the high computational complexity of the latter, the new topology is more convenient when modeling more complex systems; being this characteristic the main contribution of the AHC-algorithm, allowing it to be a more adaptable, dynamic, and reconfigurable topology. Likewise, we compared the results of the AHC-algorithm against the outcomes derived from an ARIMA model; we also made a cross-reference contrast against results concerning the prediction of other stock market indices using former state-of-the-art machine learning methods. The proficiency of the AHC-algorithm is assessed by doing a forecast of the IPC Mexico index obtaining good results, achieving a computed R-square of 0.9919, and an 8×10-4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$8\ imes 10^{-4}$$\\end{document} mean relative error for the forecast.

A Sodium Metal-Organic Framework with Deep Blue Room-Temperature Phosphorescence.

It is a great challenge to manufacture room-temperature blue long afterglow phosphorescent materials adapted to environmental conditions. Herein, an Na-based metal-organic framework (MOF) was constructed using Na+ and 1H-1,2,4-triazole-3,5-dicarboxylic acid, which exhibits long-lived of 378.9 ms, deep blue and room-temperature phosphorescence, meanwhile possesses the visible blue afterglow for 3~6 seconds after removing excitation light source. The three-dimensional coordination bonds network provided by Na-based MOF protects the organic ligands intrinsic hydrogen bond network, resulting in the phosphor lifetime and residual color remaining unchanged in different gas atmospheres. Furthermore, first-principles time-dependent density functional theory reveals that the rigid Na-based MOF structure can limit the rotation and vibration of the room-temperature phosphorescent organic ligands. This limitation results in the suppression of non-radiative decay for both singlet and triplet excitons, promotes intersystem crossing, and increases the rate of radiative decay, ultimately achieving long-lived room-temperature phosphorescence.

Adjustable structures and anti-fouling covalent organic networks membranes for precise organic small molecules separation

Covalent organic networks (CONs) membranes show unprecedented potential for the separation of organic small molecules owing to their adjustable structure and surface properties. Despite the variety of methodologies available for synthesizing CONs membranes, the preparation of CONs membranes by interfacial polymerization (IP) at 25 °C in a shorter period of time remains a great challenge. In this work, a highly anti-fouling EDA-TPA CONs composite nanofiltration (NF) membrane with adjustable structure was constructed by rapid IP of amine (ethylenediamine, EDA) and aldehyde (terephthalaldehyde, TPA) at 25 °C for 3 h. EDA-TPA CONs composite membranes showed good selectivity for most common organic small molecules, achieving a permeance of 35 L h−1 m−2 bar−1. Moreover, with respect to anti-fouling properties, the EDA-TPA CONs composite membranes exhibited a 96 % flux recovery ratio (FRR) during bovine serum albumin (BSA) filtration, reflecting an 81 % improvement compared to the control membranes (hydrolyzed polyacrylonitrile, HPAN). In addition, the EDA-TPA CONs composite membranes displayed robust comprehensive stability after continuous operation of 480 min, 5 times of cyclic testing, 180 min of continuous ultrasound at 16 kHZ and 24 h of mechanical agitation at 100 rpm. After these extensive evaluations, the EDA-TPA CONs composite membranes still retained their original separation efficacy. This study provides a fast and mild preparation process to fabricate the high performance CONs composite membranes with good anti-fouling performance and stability for treatment of organic small molecules in wastewater.

An advanced sensitive detection method for internal and external exposures assessment of para-phenylenediamines and their quinone derivatives based on hierarchical pore-structured nitro-microporous organic networks

para-Phenylenediamines (PPDs) and their quinone derivatives (PPD-Qs) are emerging pollutants that are associated with neurotoxicity, reproductive toxicity, and genetic toxicity, raising significant public health concerns globally. In this study, a novel hierarchical pore-structured nitro-microporous organic networks (NO2-MONs) characterized by multiple adsorption interactions and rapid mass transfer rates was synthesized. Model fitting and adsorption experiments confirmed diverse interaction mechanisms, including pore effects, hydrogen bonding, π-π stacking, and hydrophobic interactions. Utilizing these advantages, NO2-MONs-coated solid-phase microextraction fibers facilitated the effective extraction of trace PPDs and PPD-Qs. Subsequently, a highly sensitive analytical approach was developed for detecting trace amounts of PPDs and PPD-Qs using GC-MS/MS analysis. This method significantly improved upon existing techniques, addressing the low accuracy associated with current semi-quantitative methods and enhancing sensitivity by two orders of magnitude. Notably, the achieved detection limits ranged from 0.38 to 2.6 pg mL−1, with recovery rates between 75.7 % and 117.5 % (RSD ≤ 9.8 %). This proposed approach provides technical support for investigating concentration-dose-effect relationships related to the environmental presence of PPDs and PDD-Qs, facilitating the development of relevant regulatory standards.

Self-Aggregation Control of Porphyrin for Enhanced Selective Covalent Organic Network Membranes.

Covalent organic networks (CONs) are considered ideal for precise molecular separation compared with traditional polymer membranes because their pores have a sharp molecular weight cut-off and a robust structure. However, challenges remain with regard to tuning pores as a prerequisite for facile membrane fabrication to a defect-free layer. Herein, a highly conjugated amino-porphyrin is used and exploited its tunable stacking behavior to fabricate porphyrin-based polyamide CONs with ordered structures through interfacial polymerization with acyl chlorides. Controlling the self-aggregation behavior of the porphyrin and the conformation of the acyl chlorides can create different covalent networks. Acid-triggered porphyrin protonation offsets stacking to reduce the pore in the network from mesopore to micropore, enabling selective molecule transport. Furthermore, different acyl chloride ligands are used to control the interlayer bonding in CONs. Accordingly, the tailored pore diameters (0.48-0.78nm) are confirmed by the molecule rejections with performance stability over 25 days of operation, as well as under various conditions. This study leverages porphyrin chemistry and interfacial polymerization to fabricate a defect-free CON layer with a significantly lower molecular weight cut-off (< 330Da) than previously reported porphyrin-based membranes (>800Da). This will pave the way for the development of ideal topological membranes.

The Power of Hidden Teams: Leveraging Informal Relationships to Drive Organizational Success

This article explores the importance of informal networks, or "hidden teams", that exist within organizations alongside formal hierarchical structures, as research has shown these organic relationship-based networks play a key role in knowledge sharing, innovation, and driving work forward through efficient exchange of ideas and solutions across boundaries in communities of practice and "invisible colleges", while teams that bridge different professional communities are better able to solve complex problems. The article provides recommendations for how leaders can identify, support, and leverage hidden teams to drive business success by mapping networks through analysis and employee surveys to uncover natural collaborations, supporting hidden teams through dedicating time and space for collaboration, cross-pollinating memberships, institutionalizing information flows, and recognizing contributions, as demonstrated through two case studies where a technology company and healthcare system identified existing hidden teams, formalized roles and support, and achieved rapid, grassroots change and meaningful business impacts, suggesting that viewing informal networks as assets that break down silos and strengthen connections across groups can empower change and improve organizational performance.

The Contralateral Lung: An Opportunity for Lung Transplant at a Lower Lung Allocation Score?

BackgroundIn more than half of single-lung transplants (SLTs), the second or contralateral lung is discarded. We evaluated the use of the contralateral lung and its role in enabling single-lung transplantation at a lower Lung Allocation Score (LAS). MethodsWe identified adult SLT recipients from 2015 to 2022 using the United Network for Organ Sharing/Organ Procurement and Transplantation Network database. Post-SLT survival was compared with Kaplan-Meier curves and multivariable Cox regression. ResultsOf 4692 SLT recipients, 1246 (26.6%) received a contralateral lung. Contralateral lung recipients had a lower median LAS (36.9 [33.5-42.2] vs 40.4 [35.3-49.8]; P < .001) and higher median sequence number (26 [11-65.8] vs 8 [3-25]; P < .001). Survival was higher in contralateral vs first SLT recipients (median survival, 5.0 [95% CI, 4.7-5.3] years vs 4.5 [95% CI, 4.2-4.7] years; log-rank P < .001). This difference persisted as a 14% decreased hazard of mortality for contralateral recipients after adjustment (adjusted hazard ratio, 0.86 [0.77-0.95]; P = .004). Of SLT donors, 1309 (37.4%) had both lungs accepted for use. ConclusionsIn this nationwide analysis, we found that contralateral SLT recipients received SLTs at a lower median LAS without compromising outcomes, suggesting that contralateral single-lung transplantation may provide a valuable approach to help expand the donor pool.