Research Progress on Active Ingredients and Product Development of Lycium ruthenicum Murray.

Lycium ruthenicum Murray possesses significant applications in both food and medicine, including antioxidative, anti-tumor, anti-fatigue, anti-inflammatory, and various other effects. Consequently, there has been a surge in research endeavors dedicated to exploring its potential benefits, necessitating the organization and synthesis of these findings. This article systematically reviews the extraction and content determination methods of active substances such as polysaccharides, anthocyanins, flavonoids, and polyphenols in LRM in the past five years, as well as some active ingredient composition determination methods, biological activities, and product development. This review is divided into three main parts: extraction and determination methods, their bioactivity, and product development. Building upon prior research, we also delve into the economic and medicinal value of Lycium ruthenicum Murray, thereby contributing significantly to its further exploration and development. It is anticipated that this comprehensive review will serve as a valuable resource for advancing research on Lycium ruthenicum Murray.

Precisely Engineering Asymmetric Atomic CoN4 by Electron Donating and Extracting for Oxygen Reduction Reaction.

The development of nonpyrolytic catalysts featuring precisely defined active sites represents an effective strategy for investigating the fundamental relationship between the catalytic activity of oxygen reduction reaction (ORR) catalysts and their local coordination environments. In this study, we have synthesized a series of model electrocatalysts with well-defined CoN4 centers and nonplanar symmetric coordination structures. These catalysts were prepared by a sequential process involving the chelation of cobalt salts and 1,10-phenanthroline-based ligands with various substituent groups (phen(X), where X=OH, CH3, H, Br, Cl) onto covalent triazine frameworks (CTFs). By modulating the electron-donating or electron-withdrawing properties of the substituent groups on the phen-based ligands, the electron density surrounding the CoN4 centers was effectively controlled. Our results demonstrated a direct correlation between the catalytic activity of the CoN4 centers and the electron-donating ability of the substituent group on the phenanthroline ligands. Notably, the catalyst denoted as BCTF-Co-phen(OH), featuring the electron-donating OH group, exhibited the highest ORR catalytic activity. This custom-crafted catalyst achieved a remarkable half-wave potential of up to 0.80 V vs. RHE and an impressive turnover frequency (TOF) value of 47.4×10-3 Hz at 0.80 V vs. RHE in an alkaline environment.

Elaborate Modulating Binding Strength of Intermediates via Three-component Covalent Organic Frameworks for CO2 Reduction Reaction.

The catalytic performance for electrocatalytic CO2 reduction reaction (CO2RR) depends on the binding strength of the reactants and intermediates. Covalent organic frameworks (COFs) have been adopted to catalyze CO2RR, and their binding abilities are tuned via constructing donor-acceptor (DA) systems. However, most DA COFs have single donor and acceptor units, which caused wide-range but lacking accuracy in modulating the binding strength of intermediates. More elaborate regulation of the interactions with intermediates are necessary and challenge to construct high-efficiency catalysts. Herein, the three-component COF with D-A-A units was first constructed by introducing electron-rich diarylamine unit, electron-deficient benzothiazole and Co-porphyrin units. Compared with two-component COFs, the designed COF exhibit elevated electronic conductivity, enhanced reducibility, high efficiency charge transfer, further improving the electrocatalytic CO2RR performance with the faradic efficiency of 97.2 % at -0.8 V and high activity with the partial current density of 27.85 mA cm-2 at -1.0 V which exceed other two-component COFs. Theoretical calculations demonstrate that catalytic sites in three-component COF have suitable binding ability of the intermediates, which are benefit for formation of *COOH and desorption of *CO. This work offers valuable insights for the advancement of multi-component COFs, enabling modulated charge transfer to improve the CO2RR activity.

What Happens to a Pyrrole Hemithioindigo Photoswitch Trapped in a Fluorescent Protein?

Artificial molecular photoswitches that can be reversibly controlled into different configurations by external light stimulation have broad application prospects in various fields, such as materials and chemical biology. Among them, the pyrrole hemithioindigo (PHT) photoswitch has a geometric structure similar to that of the fluorescent protein chromophore. What happens when the chromophore is replaced by PHT, and does it achieve similar functions to the original one? To answer these questions, we carried out ONIOM(QM/MM) and classical molecular dynamics studies on the photoisomerization mechanism and spectroscopic properties of PHT in the fluorescent protein. The results showed that in the protein environment, the fate of excited PHT is governed by the competition between fluorescence emission and hula-twist isomerization. Due to the strong steric hindrance effects caused by the interlacing residues in the protein that restrict the PHT conformation transformation, the cis-to-trans isomerization process of PHT needs to overcome a barrier of at least 4.9 kcal/mol; thus, fluorescence emission is more dominant in competition. It is also found that the intermolecular interaction between LYS67 and the carbonyl oxygen of PHT has a significant effect on the fluorescence emission. These results revealed the photochemical reaction mechanism of a light-driven molecular switch in the fluorescent protein and provided further theoretical support for the field of chemical biology.

Theoretical Study on the Mechanism of Cobalt-Catalyzed C-O Silylation and Stannylation.

Organosilicon and organotin compounds have been widely used in many fields, such as organic synthesis, materials science, and biochemistry, because of their unique physical and electronic properties. Recently, two novel compounds containing C-Si or C-Sn bonds have been synthesized. These compounds can be used for late modification of drug-like molecules such as probenecid, duloxetine, and fluoxetine derivatives. However, the detailed reaction mechanisms and the influencing factors that determine selectivity are still unclear. Moreover, several questions remain that are valuable to investigate further, such as (1) the influence of the solvent and the lithium salt on the reaction of the Si/Sn-Zn reagent, (2) the stereoselective functionalization of C-O bonds, and (3) the differences between silylation and stannylation. In the current study, we have explored the above issues with density functional theory and have found that stereoselectivity was most likely caused by the oxidative addition of cobalt to the C-O bond of alkenyl acetate with chelation assistance and that transmetalation was most likely the rate-determining step. For Sn-Zn reagents, the transmetalation was achieved by anion and cation pairs, whereas for Si-Zn reagents, the process was facilitated by Co-Zn complexes.

Rational Design of Vinylene-Linked Covalent Organic Frameworks for Modulating Photocatalytic H2 Evolution.

Vinylene-linked covalent organic frameworks (COFs) have attracted enormous attention for photocatalytic H2 evolution from water because of their fully conjugated structures, high chemical stabilities, and enhanced charge-carrier mobilities. In this work, two novel vinylene-linked COFs with tuned cyano contents were successfully synthesized and then employed as photocatalysts for H2 generation. Notably, the photocatalytic H2 production rate of the COF with the higher cyano content reached 73 µmol h-1 under visible light irradiation, which is 2.4 times higher than that with the lower content (30 µmol h-1 ). Both the experimental and computational results demonstrated that the rational design incorporating cyano groups into COF skeletons could precisely tune the corresponding energy levels, expand the visible-light absorption, and improve the photoinduced charge separation. This work not only provides a simple method for modulating the photocatalytic activities of COFs at the molecular level, but also affords interesting insights into the relationship between their structures and photocatalytic performance.

Post-synthetic modification of covalent organic frameworks for CO2 electroreduction.

To achieve high-efficiency catalysts for CO2 reduction reaction, various catalytic metal centres and linker molecules have been assembled into covalent organic frameworks. The amine-linkages enhance the binding ability of CO2 molecules, and the ionic frameworks enable to improve the electronic conductivity and the charge transfer along the frameworks. However, directly synthesis of covalent organic frameworks with amine-linkages and ionic frameworks is hardly achieved due to the electrostatic repulsion and predicament for the strength of the linkage. Herein, we demonstrate covalent organic frameworks for CO2 reduction reaction by modulating the linkers and linkages of the template covalent organic framework to build the correlation between the catalytic performance and the structures of covalent organic frameworks. Through the double modifications, the CO2 binding ability and the electronic states are well tuned, resulting in controllable activity and selectivity for CO2 reduction reaction. Notably, the dual-functional covalent organic framework achieves high selectivity with a maximum CO Faradaic efficiency of 97.32% and the turnover frequencies value of 9922.68 h-1, which are higher than those of the base covalent organic framework and the single-modified covalent organic frameworks. Moreover, the theoretical calculations further reveal that the higher activity is attributed to the easier formation of immediate *CO from COOH*. This study provides insights into developing covalent organic frameworks for CO2 reduction reaction.

Cd(II)/Mn(II)/Co(II)/Ni(II)/Zn(II) Coordination Polymers Built from Dicarboxylic Acid/Tetracarboxylic Acid Ligands: Their Structural Diversity and Fluorescence Properties.

Six Cd(II)/Mn(II)/Co(II)/Ni(II)/Zn(II) coordination complexes are formulated as [Cd2(X2-)2(µ3-O)2/3]n (1), [Mn2(X2-)2(µ3-O)2/3]n (2), {[Co1.5(Y4-)0.5(4,4'-bpy)1.5(OH-)]·2H2O}n (3), {[Ni(X2-)(4,4'-bpy)(H2O)2]·4H2O}n (4), [Zn(m-bdc2-)(bebiyh)]n (5), and [Cd(5-tbia2-)(bebiyh)]n (6) (H2X = 3,3'-(2,3,5,6-tetramethyl-1,4-phenylene) dipropionic acid. H4Y = 2,2'-(2,3,5,6-tetramethyl-1,4-phenylene)bis(methylene) dimalonic acid, bebiyh = 1,6-bis(2-ethyl-1H-benzo[d]imidazol-1-yl)hexane, m-H2bdc = 1,3-benzenedicarboxylic acid, and 5-H2tbia = 5-(tert-butyl)isophthalic acid) were obtained by hydrothermal reactions and structurally characterized. Complexes 1 and 2 have a 6-connected 3D architecture and with several point symbols of (36·46·53). Complex 3 features a 5-connected 3D net structure with a point symbol of (5·69). Complex 4 possesses a 4-connected 2D net with a vertex symbol of (44·62). Complex 5 is a 3-connected 2D network with a point symbol of (63). Complex 6 is a (3,3)-connected 2D network with a point symbol of (63)2. In addition, complexes 1 and 4 present good photoluminescence behaviors. The electronic structures of 1 and 4 were investigated with the density functional theory (DFT) method to understand the photoluminescence behaviors.

Study on Fluorescence Recognition of Fe3+, Cr2O72- and p-Nitrophenol by a Cadmium Complex and Related Mechanism.

The effective detection of environmental pollutants is very important to the sustainable development of human health and the environment. A luminescent Cd(II) coordination complex, {[Cd(dbtdb)(1,2,4-H3btc)]·0.5H2O}n (1) (dbtdb = 1-(2,3,5,6-tetramethyl-4-((2-(thiazol-4-yl)-2H-benzo[d]imidazol-3(3aH)-yl)methyl)benzyl)-2,7a-dihydro-2-(thiazol-4-yl)-1H-benzo[d]imidazole, 1,2,4-H3btc = 1,2,4-benzenetricarboxylic acid), was obtained by hydrothermal reactions. Complex 1 has a chain structure decorated with uncoordinated Lewis basic O and S donors and provides good sensing of Fe3+, Cr2O72-, and p-nitrophenol with fluorescence quenching through an energy transfer process. The calculated binding constants were 3.3 × 103 mol-1 for Fe3+, 2.36 × 104 mol-1 for Cr2O72-, and 9.3 × 103 mol-1 for p-nitrophenol, respectively. These results show that 1 is a rare multiresponsive sensory material for efficient detection of Fe3+, Cr2O72-, and p-nitrophenol.

Theoretical study on hydrogen transfer in the dissociation of dimethyl disulfide radical cations.

Hydrogen transfer (HT) is of crucial importance in biochemistry and atmospheric chemistry. Here, HT processes involved in the dissociation reaction of dimethyl disulfide radical cations (DMDS˙+, CH3SSCH3˙+) are investigated using quantum chemical calculations. Four HTs from the C to S atom and one HT from the S to S atom are observed and the most probable paths are proposed in the dissociation channel from DMDS˙+ to CHnS+ (n = 2-4). The mechanisms of all these five HTs are described as hydrogen atom transfer (HAT) and four of them are accompanied by electron transfer (ET). Considering the catalytic effect of water molecules existing in organisms and the atmosphere, five HT processes in the dissociation of the [DMDS + H2O]˙+ complex are further explored, which show lower free energy barriers. With the participation of water molecules acting as a base, two HTs from the C to the S atom, which have the largest decrease in energy barriers, are characterized as concerted proton-coupled electron transfer (cPCET). These results can be extended to understand the mechanism of the HT process during the dissociation of disulfide and help provide a strategy to design a rare cPCET mechanism for the activation of the C-H bond.

One-Dimensional Covalent Organic Frameworks for the 2e- Oxygen Reduction Reaction.

Two-dimensional covalent organic frameworks (2D COFs) are often employed for electrocatalytic systems because of their structural diversity. However, the efficiency of atom utilization is still in need of improvement, because the catalytic centers are located in the basal layers and it is difficult for the electrolytes to access them. Herein, we demonstrate the use of 1D COFs for the 2e- oxygen reduction reaction (ORR). The use of different four-connectivity blocks resulted in the prepared 1D COFs displaying good crystallinity, high surface areas, and excellent chemical stability. The more exposed catalytic sites resulted in the 1D COFs showing large electrochemically active surface areas, 4.8-fold of that of a control 2D COF, and thus enabled catalysis of the ORR with a higher H2 O2 selectivity of 85.8 % and activity, with a TOF value of 0.051 s-1 at 0.2 V, than a 2D COF (72.9 % and 0.032 s-1 ). This work paves the way for the development of COFs with low dimensions for electrocatalysis.

Heterogeneous electro-Fenton using three-dimension Fe-Co-Bi/kaolin particle electrodes for degradation of quinoline in wastewater.

Wastewater containing quinoline has become a common pollutant in water and soil environments, which poses a threat to human health due to its carcinogenicity, teratogenicity, and mutagenicity. Quinoline's stability and toxicity hinders its degradation by conventional physicochemical and biological methods. In this contribution, Fe-Co-Bi/kaolin particle electrodes were prepared for the efficient degradation of quinoline in wastewater, and characterized by using scanning electron microscope, X-ray diffraction, pyridine-IR, Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy, and four-probe resistivity test. Parameters affecting the degradation efficiency were optimized to be the particle electrode dosage of 40 g/L, pH 3.5, H2O2 addition of 67.6 mmol/L, electrical conductivity of 12.7 ms/cm, and voltage of 20 V. The constructed three-dimensional catalytic particle electrode system (3D-CPE) achieved 92.1% removal rate of chemical oxygen demand (COD) under the optimal conditions. Hydroxyl radicals (•OH) generated in the 3D-CPE process were identified by radical scavenging tests and electron spin response analysis. To unravel the degradation mechanism, the intermediate products were identified by using high performance liquid chromatography-mass spectrometry. The degradation mechanism was discussed with the help of theoretical calculation.

Construction of Catalytic Covalent Organic Frameworks with Redox-Active Sites for the Oxygen Reduction and the Oxygen Evolution Reaction.

Construction of catalytic covalent organic frameworks (COFs) for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is significant but rarely demonstrated. In this work, we have first constructed bifunctional COFs towards ORR and OER by integrating diarylamine derivatives into the Co-porphyrin based frameworks. Both of the new COFs (CoTAPP-PATA-COF and CoTAPP-BDTA-COF) have good ordered structures, high surface areas, and robust chemical stability. The diarylamine units, as a typical electron donor and redox-active cores, promote intramolecular electron transport along the frameworks and improve the electrochemically active surface areas. Thus, the COFs showed higher catalytic activities than that of the COF without redox-active units. CoTAPP-PATA-COF had a halfwave potential of 0.80 V towards ORR, and delieved an overpotential of 420 mV for OER in 0.1 M KOH. The theoretical calculation revealed introducing diarylamine unites improved the oxygen electrocatalysis.

Covalent Organic Frameworks with Tailored Functionalities for Modulating Surface Potentials in Triboelectric Nanogenerators.

Designing materials with high triboelectric is an efficient way of improving output performance of triboelectric nanogenerators (TENGs). Herein, we synthesized a series of covalent organic frameworks (COFs) with similar skeletons but various functional groups ranging between electron-donating and electron-withdrawing. These COFs form an ideal platform for clarifying the contribution of each group to TENG performance because the pore wall is perturbed in a predesigned manner. Kelvin probe force microscopy and computational data suggest that surface potentials and electron affinities of COFs can be improved by introducing electron-donating or withdrawing groups, with the highest values observed for fluorinated COF. The TENG with fluorinated COF delivered an output voltage and current of 420 V and 64 µA, respectively, which are comparable to other reported materials. This strategy can be used to efficiently screen suitable frameworks as TENG materials with excellent output performance.

Porphyrin-based conjugated organic polymer with dual metal sites for highly active and selective visible-light-driven reduction of CO2 to CO.

A porphyrin-based conjugated organic polymer (COP) was constructed from 5,10,15,20-tetrakis(4-bromophenyl)porphyrin copper (CuTBPP) and 5,5'-bis-ethynyl-2,2'-bipyridine (BPY) via Sonogashira coupling. Its complex Co/CuTBPP-BPY-COP (with dual metal sites composed of copper porphyrin and a cobalt BPY unit) was prepared by coordination with Co2+. All of the prepared CuTBPP-BPY-COP and Co/CuTBPP-BPY-COP compounds exhibited excellent photocatalytic performance toward CO2 reduction under visible-light irradiation without another sacrificial reagent but only H2O. Co/CuTBPP-BPY-COP (dual metal sites) exhibited better photocatalytic activity than CuTBPP-BPY-COP (a single metal site). Co/CuTBPP-BPY-COP retained a higher photocatalysis capacity for CO2 reduction after 10 consecutive cycles. The total quantity of CO product was 263.2 µmol g-1 after 10 h of irradiation. Theoretical studies indicate that introducing Co metal centers and nitro groups are more favorable for the photoreduction catalysis of CO2 compared with that using CuTBPP-BPY-COP.

CoN5 Sites Constructed by Anchoring Co Porphyrins on Vinylene-Linked Covalent Organic Frameworks for Electroreduction of Carbon Dioxide.

Developing effective electrocatalysts for CO2 reduction (CO2 RR) is of critical importance for producing carbon-neutral fuels. Covalent organic frameworks (COFs) are an ideal platform for constructing catalysts toward CO2 RR, because of their controllable skeletons and ordered pores. However, most of these COFs are synthesized from Co-porphyrins or phthalocyanines-based monomers, and the available building units and resulting catalytic centers in COFs are still limited. Herein, Co-N5 sites are first developed through anchoring Co porphyrins on an olefin-linked COF, where the Co active sites are uniformly distributed in the hexagonal networks. The strong electronic coupling between Co porphyrins and COF is disclosed by various characterizations such as X-ray absorption spectroscopy (XAS) and density functional theory calculation (DFT). Thanks to the CoN5 sites, the catalytic COF shows remarkable catalytic activity with Faraday efficiencies (FECO ) of 84.2-94.3% at applied potentials between -0.50 and -0.80 V (vs RHE), and achieves a turnover frequency of 4578 h-1 at -1.0 V. Moreover, the theoretical calculation further reveals that the CoN5 sites enable a decrease in the overpotential for the formation COOH*. This work provides a design strategy to employ COFs as scaffold for fabricating efficient CO2 electrocatalysts.

Smart Titanium Wire Used for the Evaluation of Hydrophobic/Hydrophilic Interaction by In-Tube Solid Phase Microextraction.

Evaluation of the hydrophobic/hydrophilic interaction individually between the sorbent and target compounds in sample pretreatment is a big challenge. Herein, a smart titanium substrate with switchable surface wettability was fabricated and selected as the sorbent for the solution. The titanium wires and meshes were fabricated by simple hydrothermal etching and chemical modification so as to construct the superhydrophilic and superhydrophobic surfaces. The micro/nano hierarchical structures of the formed TiO2 nanoparticles in situ on the surface of Ti substrates exhibited the switchable surface wettability. After UV irradiation for about 15.5 h, the superhydrophobic substrates became superhydrophilic. The morphologies and element composition of the wires were observed by SEM, EDS, and XRD, and their surface wettabilities were measured using the Ti mesh by contact angle goniometer. The pristine hydrophilic wire, the resulting superhydrophilic wire, superhydrophobic wire, and the UV-irradiated superhydrophilic wire were filled into a stainless tube as the sorbent instead of the sample loop of a six-port valve for on-line in-tube solid-phase microextraction. When employed in conjunction with HPLC, four kinds of wires were comparatively applied to extract six estrogens in water samples. The optimal conditions for the preconcentration and separation of target compounds were obtained with a sample volume of 60 mL, an injection rate of 2 mL/min, a desorption time of 2 min, and a mobile phase of acetonile/water (47/53, v/v). The results showed that both the superhydrophilic wire and UV-irradiated wire had the highest extraction efficiency for the polar compounds of estrogens with the enrichment factors in the range of 20-177, while the superhydrophobic wire exhibited the highest extraction efficiency for the non-polar compounds of five polycyclic aromatic hydrocarbons (PAHs). They demonstrated that extraction efficiency was mainly dependent on the surface wettability of the sorbent and the polarity of the target compounds, which was in accordance with the molecular theory of like dissolves like.

Brass wires with different surface wettability used for in-tube solid-phase microextraction.

Metal wires have been widely used as substrates for solid-phase microextraction (SPME) fibers instead of commonly fragile silica fibers, but complicated coating modification of their surface is required. Herein, a series of brass wires were soaked in an acidic iron trichloride solution with ultrasonication, which etched the brass surface through a redox reaction. The surface wettability of the pristine brass wire was transformed from hydrophobic to hydrophilic owing to the formation of micro/nanoscale hierarchical structures. After modification with n-octadecanethiol (ODT) and 2-naphthalenethiol (NT), respectively, both wires exhibited superhydrophobicity. Characterization of the resulting wires was conducted using SEM and EDS, and the surface wettability was measured by a contact angle goniometer using identical brass meshes. To build an in-tube SPME-high-performance liquid chromatography (HPLC) online system, the extraction tube was connected with HPLC equipment by replacing the sample loop of a six-port valve. Four types of wires, including the pristine hydrophobic brass wire, the hydrophilic wire after chemical etching, and both superhydrophobic wires, were comparatively applied to the extraction of six estrogens. The optimized extraction conditions were a sample volume of 60 mL, an injection rate of 2 mL/min, and a desorption time of 2 min at a flow rate of 1 mL/min. The results showed that the highest estrogen extraction efficiency was obtained using the superhydrophobic wire modified by NT, with the enrichment factors in the range of 36-350. Furthermore, the superhydrophobic NT wire exhibited a higher extraction efficiency than the ODT wire with identical superhydrophobicity. This demonstrated that the higher extraction efficiency was mainly dependent on  π-π interactions between the sorbent containing naphthalene rings and the target compounds containing benzene rings, rather than surface wettability.

Theoretical Study on Storage and Release of Firefly Luciferin.

Among numerous bioluminescent organisms, firefly is the most studied one. Recent experiment proposed that sulfoluciferin (SLH2 ) may serve as a storage form of luciferin (LH2 ). In the present article, we employed density functional theory calculation to uncover the mechanism and detailed process of the storage and release reactions. Due to lack of available crystallographic structure of the related enzyme, the calculation was performed on a model system. For the storage reaction, possible amino acid residues were used for imitating the protein environment. For the release reaction, the dielectric constant of 3.0 was employed to simulate the polarity of the protein cavity. The computational results indicated that the reactions from LH2 to SLH2 and from SLH2 to LH2 are both exergonic, which favor the storage and release processes and coincide with the experimental observation. Basing on experimental and current theoretical study, we supplemented the stages of LH2 storage and release in the entire bioluminescent cycle of firefly. The current theoretical calculation could inspire the study on LH2 storage and release of other bioluminescent organisms.

Anticancer Drug Release System Based on Hollow Silica Nanocarriers Triggered by Tumor Cellular Microenvironments.

Targeted release of anticancer drugs to tumor sites has a pivotal role in clinical oncology. pH-responsive drug delivery systems, with an intelligent and targeted release of anticancer drugs in a controllable manner based on sensitivities to the weakly acidic environments of tumor cellular microenvironments, are desirable. Herein, the design of such a pH-responsive drug delivery system is detailed using in situ amino-functionalized hollow mesoporous silica nanoparticles as carriers. The drug release behavior of the pH-responsive delivery system was evaluated under an in vitro simulation of tumor cellular microenvironments. The drug delivery system has efficient drug loadings and targeted release. Zorubicin hydrochloride releasing percentage is almost up to 100% at a buffer pH of 5.0. The drug release systems described demonstrating great potential in anticancer therapy.