Synthesis, characterization, solution chemistry and anticancer activity of [NiCl2(Ph2P-N(R)-PPh2)] (R = 2-CH2Py, CH2Ph and p-tol) complexes

In this work three Ni²⁺ complexes with general formula [NiCl₂(Ph₂P-N(R)-PPh₂)], R = 2-CH₂Py (Py = pyridine) - 1, CH₂Ph (Ph = phenyl) - 2 and p-tol (p-tol = p-tolyl) - 3, were synthesized and characterized. These complexes were obtained in high yield by the reaction of NiCl₂.6H₂O and the corresponding diphenylphosphinoamine ligand (Ph₂P-N(R)-PPh₂) in CH₂Cl₂/MeOH (1:1) solution, at room temperature (∼25 °C), and characterized by ¹H and ³¹P {¹H} NMR, vibrational spectroscopy in the infrared region, electronic spectroscopy in the UV-Vis regions, elemental analysis (%C, %H, %N) and single-crystal X-ray diffraction. The solution chemistry was studied in CDCl₃/dmso-d⁶ (dimethylsulfoxide) or neat dmso-d⁶ using complex 2 as a model. The complexes were evaluated as cytotoxic agents against two cancer cells lines, A549 (lung cancer cells), B16F10 (melanoma cells) and the health cells HaCaT (human epithelial keratinocytes).

Preparation and properties of phosphinic acid-functionalized polyacrylonitrile hollow fiber membrane for heavy metal adsorption

In this study, phosphorylated polyacrylonitrile hollow fiber membrane was synthesized by reacting aminated polyacrylonitrile hollow fiber membrane with phosphinic acid in a Mannich reaction. The batch single-factor measurements revealed that the phosphorylated polyacrylonitrile (PPAN) membrane had an outstanding ability for Hg²⁺ adsorption. Thermodynamic investigations indicated that the adsorption process was homogenous, and the theoretical maximum adsorption capacity predicted by the Langmuir model was 371.75 mg·g^-1. The PPAN membrane was able to successfully chelate Hg²⁺ ions and attain saturation in 4 h, demonstrating that the reaction was chemically controlled by the adsorption kinetics. Based on the FT-IR and XPS spectral characterization data, successful phosphinic acid group grafting was proven, and a plausible mechanism for Hg²⁺ adsorption by PPAN membranes was presented. Furthermore, the five adsorption-desorption cycle experiments revealed that PPAN hollow fiber membranes had outstanding reusability, indicating a possible use for removing heavy metal ions from wastewater.

Selective NOx- Electroreduction to Ammonia on Isolated Ru Sites

Nitrate and nitrite (NO_x^-) are widespread contaminants in industrial wastewater and groundwater. Sustainable ammonia (NH₃) production via NO_x^- electroreduction provides a prospective alternative to the energy-intensive industrialized Haber-Bosch process. However, selectively regulating the reaction pathway, which involves complicated electron/proton transfer, toward NH₃ generation relies on the robust catalyst. A specific consideration in designing selective NO_x^--to-NH₃ catalysts should meet the criteria to suppress competing hydrogen evolution and avoid the presence of neighboring active sites that are in favor of adverse N-N coupling. Nevertheless, efforts in this regard are still inadequate. Herein, we demonstrate that isolated ruthenium sites can selectively reduce NO_x^- into NH₃, with maximal Faradaic efficiencies of 97.8% (NO₂^- reduction) and 72.8% (NO₃^- reduction) at -0.6 and -0.4 V, respectively. Density functional theory calculations simulated the reaction mechanisms and identified the *NO → *NOH as the potential rate-limiting step for NO_x^--to-NH₃ conversion on single-atom Ru sites.

Separation performance of the calix[8]arene functionalized with polyethylene glycol units for capillary gas chromatography

In this paper, an amphiphilic calix[8]arene with polyethylene glycol unit branches (C8A-PEG) was synthesized and applied for capillary gas chromatography (GC). The C8A-PEG was coated on the inner wall of a capillary column by a static method with the column efficiency of 3165 plates/m and polar nature. As demonstrated, the C8A-PEG column has excellent physicochemical properties and separation performance since it has π-electron-rich 3D cavity which combines with polar PEG units. Compared with two columns corresponding to the construction units C8A and PEG, the C8A-PEG column shows distinctly advantageous performance for the mixture of 22 components with diverse types. Impressively, it shows satisfactory resolution for positional isomers and cis-/trans- isomers, especially the challenging isomers of toluidine and dimethylaniline. The outstanding distinguishing capability of the C8A-PEG stationary phase is mainly attributed to the abundant molecular recognition interactions, including van der Waals, dipole-dipole, H-bonding and π-π stacking interactions. This work has proved that the new GC stationary phases constructed by different units can complement each other's advantages, improve their physicochemical properties and separation performance, and have broad application prospects in chromatographic analysis.

Binding and selectivity studies of phosphatidylinositol 3-kinase (PI3K) inhibitors

Overexpression of the Phosphatidylinositol 3-kinase (PI3K) proteins have been observed in cancer cells. Targeting the phosphatidylinositol 3-kinase (PI3K) signaling transduction pathway by inhibition of the PI3K substrate recognition sites has been proved to be an effective approach to block cancer progression. Many PI3K inhibitors have been developed. Seven drugs have been approved by the US FDA with a mechanism of targeting the phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway. In this study, we used docking tools to investigate selective binding of ligands toward four different subtypes of PI3Ks (PI3Kα, PI3Kβ, PI3Kγ and PI3Kδ). The affinity predicted from both the Glide dock and the Movable-Type (MT)-based free energy calculations agreed well with the experimental data. The validation of our predicted methods with a large dataset of 147 ligands showed very small mean errors. We identified residues that may dictate the subtype-specific binding. Particularly, residues Asp964, Ser806, Lys890 and Thr886 of PI3Kγ might be utilized for PI3Kγ-selective inhibitor design. Residues Val828, Trp760, Glu826 and Tyr813 may be important for PI3Kδ-selective inhibitor binding.

Dual-wideband sandwich coupled three-lines bandpass filter based on modified open-stub loaded stepped impedance resonator with improved second harmonic for 5G wi-fi/ ku-band applications

A modified open-stub-loaded three sections stepped impedance resonator (OSL-TSIR) is analysed in this paper. Based on the even- and odd-mode analysis technique, it can be easily achieved that the proposed OSL-TSIR have the advantage of improving spurious resonant mode frequencies. Besides, more degrees of freedom are provided to control the location of harmonics. A third order Chebyshev dual-wideband bandpass filter composed of cascade parallel sandwich coupled three-lines sections of types SC/CS and OSL-TSIR which act as multi-mode resonator was developed and the design procedure is described. To demonstrate the efficiency of the design process, DB-BPF operating at 5.15/12.58 GHz (2.45 f 0 ) and FBW of 19/5.7% for 5G Wi-Fi/Ku-band Applications is designed and simulated. Three transmission zeros are created, resulting in the excellent band-in-band isolation and high selectivity. The filter has a miniaturized size of 27 mm × 18 mm.

Comprehensive evaluation of zwitterionic hydrophilic liquid chromatography stationary phases for oligonucleotide characterization

Hydrophilic interaction chromatography (HILIC) has been proposed as a valuable alternative to ion-pairing reversed-phase chromatography (IP-RPLC) for oligonucleotide (ON) analysis. In this context, the potential of seven zwitterionic HILIC columns has been evaluated against amide- and poly-hydroxy fructan-functionalized HILIC columns and a C18 column operated under IP-RPLC mode. Based on the retention characteristics of key small molecule pairs, each zwitterionic HILIC column showed a unique radar-shaped profile, suggesting different selectivities for distinct structural differences. Unmodified DNA and RNA samples were then evaluated, and the columns classified based on their retentivity. Two zwitterionic columns were particularly promising in terms of overall resolution, especially for the largest ONs (> 40-mer). Finally, separations between a chemically modified drug-like ON and its closely related impurities were performed. Although the ZIC-cHILIC column showed similar selectivity values as compared to the reference IP-RPLC technique, all columns demonstrated a general decrease in selectivity due to the minor structural differences present in the highly complex samples. This work highlights the utility of zwitterionic HILIC mode for ON analysis and it reveals the importance of understanding columns characteristics - in terms of retention and selectivity - when selecting a stationary phase for specific ON applications.

Transition-Metal-Free Controllable Single and Double Difluoromethylene Formal Insertions into C-H Bonds of Aldehydes with TMSCF2 Br

We have developed a new strategy for controllable single and double difluoromethylene (CF₂ ) formal insertions into C-H bonds of aldehydes with nearly full selectivity under transition-metal-free conditions. The key to the success of controllable CF₂ insertions lies in the well-defined formation of 2,2-difluoroenolsilyl ether and 2,2,3,3-tetrafluorocyclopropanolsilyl ether intermediates using difluorocarbene reagent TMSCF₂ Br (TMS=trimethylsilyl). These two intermediates can react with various electrophiles including proton sources and various halogenation reagents, allowing for the access to diverse arrays of ketones containing difluoromethylene (CF₂ ) and tetrafluoroethylene (CF₂ CF₂ ) units. The first synthesis of relatively stable 2,2,3,3-tetrafluorocyclopropanolsilyl ethers has been achieved, which offers a new platform to explore other unknown chemical space.

Broad-class volatile organic compounds (VOCs) detection via polyaniline/zinc oxide (PANI/ZnO) composite materials as gas sensor application

Metal-oxide doped conductive polymers have been investigated as sensors in the field of gas-sensing. Recent developments have highlighted the role of intrinsically conductive polymers, that have reportedly offered high surface response towards the detection of volatile organic compounds (VOCs). In this work, we optimize the development of gas-sensors made of Polyaniline/Zinc oxide (PANI/ZnO) composite, capable of detecting a varied class of VOCs such as, ammonia, acetone, formaldehyde, methanol, and ethanol. The conductivity of these sensors is evaluated at room temperature and are investigated until saturation. In addition to the final application, this work also focusses on the synthesis strategies to achieve an 'optimal' matrix-to-additive ratio, such that superior chemical response is paralleled with mechanical robustness for PANI based sensors. The PANI/ZnO composites are casted into sensors bearing different additive ratios, via a drop-casting method and the same is evaluated for its formability and mechanical behavior. Physio-chemical characterization was performed using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), and Energy Dispersive X-ray Analysis (EDX) and we report on an exceptional selectivity for ammonia with an average sensor response of 3496.67 mV by all the sensors, when fabricated using different matrix-additive ratios. This result is superior to what is observed for Pure- PANI sensors that were selective only to methanol and ethanol. The addition of ZnO in the smallest fraction, already offers a broader range of selectivity, e.g., PANI/ZnO 90:10 sensor was selective to formaldehyde as assessed using pattern recognition.

Isoform selectivities of novel 4-hydroxycoumarin imines as inhibitors of myosin II

Muscle myosin inhibition could be used to treat many medical conditions involving hypercontractile states, including muscle spasticity, chronic musculoskeletal pain, and hypertrophic cardiomyopathy. A series of 13 advanced analogs of 3-(N-butylethanimidoyl)ethyl)-4-hydroxy-2H-chromen-2-one (BHC) were synthesized to explore extended imine nitrogen side chains and compare aldimines vs. ketimines. None of the new analogs inhibit nonmuscle myosin in a cytokinesis assay. ATPase structure-activity relationships reveal that selectivity for cardiac vs. skeletal myosin can be tuned with subtle structural changes. None of the compounds inhibited smooth muscle myosin II. Docking the compounds to homology models of cardiac and skeletal myosin II gave rationales for the effects of side arm length on inhibition selectivity and for cardiac vs. skeletal myosin. Properties including solubility, stability and toxicity, suggest that certain BHC analogs may be useful as candidates for preclinical studies or as lead compounds for advanced candidates for drugs with cardiac or skeletal muscle myosin selectivity.

3D printed optical sensor for highly sensitive detection of picric acid using perovskite nanocrystals and mechanism of photo-electron transfer

Hand-held, compact and portable sensors for on-site detection of environmental contaminants are in high demand for industry 4.0. Here, we have developed a sensor based on luminescent organic-inorganic metal halide hybrid perovskites nanocrystals (CH₃NH₃PbBr₃) with p-xylylenediamine as an additional capping agent for highly sensitive and selective detection of picric acid (PA), with a good linear range of 1.8 μM-14.3 μM achieving detection of limit (LOD) of 0.3 μM. The electrostatic interaction between PA and the capping ligand of perovskite nanocrystals resulted in significant fluorescence quenching, as revealed by the steady-state and time-resolved spectroscopy. The applicability of the developed sensor for PA detection was validated with a 3D printed device integrating surface mounting device (SMD) and paper microfluidics. This prototype device was successfully applied as a fluorescence turn-off sensor to detect PA, showing great potential for on-site detection. This 3D-printed paper-based microfluidic optical sensor proved very efficient for naked-eye detection of PA with an inbuilt excitation source, avoiding the requirement of expensive and complex instrumentation.

Design, synthesis and evaluation of antitumor activity of selective PRMT6 inhibitors

PRMT6 is a member of the protein arginine methyltransferase family, which is involved in a variety of physiological processes and plays an important role in the occurrence and development of tumors. Due to the high homology of type Ⅰ PRMTs and the two close binding sites of the SAM pocket and the substrate pocket, selective PRMT6 inhibitors have rarely been reported. In this study, a series of (5-phenylpyridin-3-yl)methanamine derivatives were designed and synthesized, which could form hydrogen bonding interactions with the unique Glu49 of PRMT6, thereby improving the selectivity of the compounds for PRMT6. Among them, a25 had the best activity and selectivity, with more than 25-fold selectivity for PRMT1/8 and more than 50-fold selectivity for PRMT3/4/5/7, which was superior to these reported SAM competitive and substrate competitive PRMT6 inhibitors. Importantly, a25 could significantly inhibit the proliferation of various tumor cells and effectively induce apoptosis of cancer cells. Our data clarified that a25 is a promising selective PRMT6 inhibitor for cancer therapy which is worthy of further evaluation.

A fluorescent assay for sensitive detection of kanamycin by split aptamers and DNA-based copper/silver nanoclusters

Kanamycin was a group of essential antibiotics generally served in treating infections of animals which leached into the environment residual in food, causing health concerns. Thus, selective and sensitive monitoring of kanamycin was significant for food safety. In this work, split aptamers were used as templates to prepare fluorescent Cu/Ag NCs for detection of kanamycin. According to the impressive affinity of the aptamer to kanamycin, two different detection modes were designed using kanamycin aptamer as a recognition molecule, in which one was to combine split aptamer Apt-1 with Apt-2 to form an entangled DNA as a Cu/Ag NCs template, the other was to associate the normal aptamer after encirclement to form Cu/Ag NCs templates. After the addition of kanamycin, the fluorescence signals of the Cu/Ag NCs synthesized in the two modes were both enhanced, but the approach with split aptamer exhibited a superior observable sensitivity than that of the normal type. The detection range showed a well linear relationship between 80 nM and 10 μM when the emission wavelength was 560 nm, and the detection limit was 13.3 nM. In addition, when streptomycin, oxytetracycline, chloramphenicol and chlortetracycline were involved in the selective interference experiment under the same conditions, the fluorescence intensity of the system performed no significant changes. The results demonstrated that this method possessed favorable specificity and selectivity for the assay of kanamycin, proficiently achieving efficient, rapid and sensitive evaluation of kanamycin in the milk samples.

Correlating Oxidation State and Surface Ligand Motifs with the Selectivity of CO2 Photoreduction to C2 Products

The design for non-Cu-based catalysts with the function of producing C₂₊ products requires systematic knowledge of the intrinsic connection between the surface state as well as the catalytic activity and selectivity. In this work, photochemical in situ spectral surface characterization techniques combined with the first principle calculations (DFT) were applied to investigate the relationships between the composition of surface states, coordinated motifs, and catalytic selectivity of a titanium oxynitride catalyst. When the catalyst mediates CO₂ photoreduction, C₂ product selectivity is positively correlated with the surface Ti²⁺ /Ti³⁺ ratio and the surface oxidation state is regulated and controlled by coordinated motifs of N-Ti-O/V[O], which can reduce the potential dimerization energy barriers of *CO-CO* and promote spontaneous formation of the subsequent *CO-CH₂ * intermediate. This phenomenon provides a new perspective for the design of heterogeneous catalysts for photoreduction of CO₂ into useful products.

Studies on nanomaterial-based p-type semiconductor gas sensors

The development of various metal oxide semiconductor materials has resulted in better performance of the gas sensors in terms of selectivity, sensitivity, and response time. Different types of nanostructured materials, i.e., 2D materials, carbon nanotubes, and metal oxides, are used in the gas sensing applications. Generally, the metal oxide-based gas sensor operates at higher temperature to activate the adsorption process between the material surface and the target gas. The higher operating temperature of the gas sensor leads to more power consumption and produces defects in the grain boundary of metal oxide. To improve the selectivity and minimize the power consumption, nanoparticle-based p-type semiconductor materials are being developed. P-type metal oxide-based semiconductor materials have the ability to produce a hole accumulation layer which can chemisorb the oxygen molecules of higher concentration and these materials are not affected by humidity. The structure of p-type nanomaterial-based gas sensor depends upon the fabrication techniques which can affect the sensing properties of semiconductor materials. The hole accumulation layer is also known as conduction layer which is developed in the outer shell of p-type semiconductor material and the sensing mechanism is controlled by grain boundaries which is different from the n-type semiconductor material. This paper reviews the preparation methods, morphological analysis, and sensing mechanisms of nanomaterial-based p-type metal oxide-based gas sensors.

Noval green sodium alginate/gellan gum aerogel with 3D hierarchical porous structure for highly efficient and selective removal of Congo red from water

Rational design of adsorbed materials with three-dimensional (3D) hierarchical porous structure, sustainable, high adsorption capacity, and excellent selective is of great significance in practical applications. Herein, a novel aerogel adsorbed material with 3D hierarchical porous architecture was fabricated by employing naturally abundant sodium alginate (SA)/gellan gum (GG) as basic construction blocks to achieve sustainability as well as applying polyethyleneimine (PEI) as functional material for highly efficient and selective capture of Congo red (CR). The aerogel sorbent exhibited strong microstructure, numerous active adsorption sites and being ultralight. The resulting aerogel adsorbent showed high adsorption capacity (3017.23 mg/g) toward CR, exceedingly most previously reported sorbents. Furthermore, the aerogel adsorbent was accompanied by outstanding selectivity for CR in four binary dye systems. Meanwhile, after 3 cycles, the adsorption capacity decreased by 14.8 %, but still maintained the adsorption capacity of 559.79 mg/g. Therefore, excellent adsorption performance, and superb selectivity prefigures its great prospects for wastewater purification.

GO/ZnO nanocomposite - as transducer platform for electrochemical sensing towards environmental applications

Graphene Oxide-Zinc Oxide (GO-ZnO) - a new nanomaterial that has queued the interest of researchers. Their intriguing promising physical and electrochemical features of electrode material have led to its widespread use in electrochemical sensor applications. GO-ZnO based nanomaterial were extensively exploited in the construction of electrochemical sensors due to their adaptability and distinct qualities. On understanding the structural role of these materials, their modification processes are critical for realizing their full potential. The advancement of technology on new concepts and strategies has revolutionized the field of sensor devices with high sensitivities and selectivity. These tools can test a range of contaminants quickly, accurately, and affordably while performing automated chemical analysis in complicated matrices. This paper highlights the electrochemical transducer surface for sensing various analytes and current research activity on GO-ZnO nanocomposite. Additionally, we talked about current developments in GO-ZnO nanostructured composites to identify relevant analytes (i.e., Nitrophenols, Antibiotic Drugs, Biomolecules). While being used in the laboratory, the majority of produced systems have proven to bring about excellent gains. Their monitoring application still has a long way to go before it is fixed due to problems like technological advancements and multifunctional strategies to get around the challenges for improving the sensing systems.

Discovery of indole-piperazine derivatives as selective histone deacetylase 6 inhibitors with neurite outgrowth-promoting activities and neuroprotective activities

Novel indole-piperazine derivatives with a hydroxamic acid moiety were designed and synthesized as selective histone deacetylase 6 (HDAC6) inhibitors. In enzymatic assays, all compounds exhibited nanomolar IC₅₀ values. N-hydroxy-4-((4-(7-methyl-1H-indole-3-carbonyl)piperazin-1-yl)methyl)benzamide, 9c, was the most potent HDAC6 inhibitor (IC₅₀, 13.6 nM). In vitro, 9c induced neurite outgrowth of PC12 cells without producing toxic effects, better than Tubastatin A (Tub A). Additionally, 9c demonstrated blatant neuroprotective activity in PC12 cells against H₂O₂-induced oxidative damage. In western blot assay, 9c could increase the acetylation of α-tubulin in a dose-dependent manner.

Plasma metabolites-based design of long-acting peptides and their anticancer evaluation

Antimicrobial peptides (AMPs) are generally small cationic amphipathic peptides, which are thought to be ideal antineoplastic agents, owing to their favorable selectivity to cancer cells and the ability to overcome drug-resistance. In this study, an anticancer AMP (Mastoparan (INLKALAALAKKIL-NH2)) was selected as the lead compound and a series of Mastoparan derivatives were designed. Preliminary studies verified that an analogue of Mastoparan, KM8 (KLLKINLKALAALAKKIL-NH2), exhibited prominent selective antitumor effects. Instead, it presents a significant defect of metabolic instability, with a half-life in plasma of only about 0.5 h. Metabolite profiling of KM8 was performed and indicated the structure ₉AL₁₀ in peptide sequence could be the fragile site for KM8. Thus, the Aib (unnatural amnio acid) was employed to substitute the ₉Ala residue in KM8, and generating a long-acting KM8 derivative, namely KM8-Aib. Further investigations revealed KM8-Aib possessed higher metabolic stability, more potent anticancer activity in vitro & in vivo, and lower toxicity. Therefore, KM8-Aib is suggested be a potential antimalignant agent that worthy of more in-depth study.

Controlling Selectivity in Plasmonic Catalysis: Switching Reaction Pathway from Hydrogenation to Homocoupling Under Visible-Light Irradiation

Plasmonic catalysis enables the use of light to accelerate molecular transformations. Its application to the control reaction selectivity is highly attractive but remains challenging. Here, we have found that the plasmonic properties in AgPd nanoparticles allowed different reaction pathways for tunable product formation under visible-light irradiation. By employing the hydrogenation of phenylacetylene as a model transformation, we demonstrate that visible-light irradiation can be employed to steer the reaction pathway from hydrogenation to homocoupling. Our data showed that the decrease in the concentration of H species at the surface due to plasmon-enhanced H₂ desorption led to the control in selectivity. These results provide important insights into the understanding of reaction selectivity with light, paving the way for the application of plasmonic catalysis to the synthesis of 1,3-diynes, and bringing the vision of light-driven transformations with target selectivity one step closer to reality.

Site-Selective Electrochemical C-H Carboxylation of Arenes with CO2

Herein, a direct, metal-free, and site-selective electrochemical C-H carboxylation of arenes by reductive activation using CO₂ as the economic and abundant carboxylic source was reported. The electrocarboxylation was carried out in an operationally simple manner with high chemo- and regioselectivity, setting the stage for the challenging site-selective C-H carboxylation of unactivated (hetero)arenes. The robust nature of the electrochemical strategy was reflected by a broad scope of substrates with excellent atom economy and unique selectivity. Notably, the direct and selective C-H carboxylation of various challenging arenes worked well in this approach, including electron-deficient naphthalenes, pyridines, simple phenyl derivatives, and substituted quinolines. The method benefits from being externally catalyst-free, metal-free and base-free, which makes it extremely attractive for potential applications.

Stabilization mechanism of Pb with an amino- and mercapto-polymer to assist phytoremediation

An important concern during phytoremediation of heavy metal contamination in soils is the risk of leaching of heavy metals before they can be taken up by plants. The most effective method is to use heavy metal stabilizers. However, the stabilization without selectivity will greatly inhibit the phytoremediation effect of all heavy metals. A novel polymer with amino and mercapto groups named as AMP has been prepared as a new exclusive soil stabilizer for Pb. The adsorption of AMP toward Pb belonged to a monolayer adsorption and chemical process. The adsorption capacity of Pb increased with the increase of pH and initial Pb concentration, and obeyed the Langmuir model and pseudo-second-order model, respectively. An amazing maximum adsorption capacity of 588 mg Pb g^-1 was reached for AMP when initial concentration was 300 mg Pb L^-1, while K₂ of 0.594 g mg^-1 min^-1 was obtained when the initial Pb concentration was 2.0 mg L^-1. The distribution coefficient of AMP to Pb in the mixture of five heavy metals was as high as 3110 mL g^-1, which was at least 7-fold greater than those of other heavy metals, exhibiting high selective to Pb. AMP showed a fast, large adsorption capacity and good selectivity due to the abundance of sulfhydryl and amino functional groups in the polymer and their interaction with metal ions. The effects of AMP in soil remediation were further tested by a soil column leaching experiment and a pot experiment, and the good stabilization effect of AMP on Pb and the less effect on bioavailability of other heavy metals at recommended doses were verified. This study was expected to solve the problem of leaching risk of the target metal such as Pb in sludge during land use. It provided a new idea of exclusive stabilization to assist phytoremediation of non-target heavy metals by reducing the leaching risk of some special target metal.

A new class of CYP1B1 inhibitors derived from bentranil

Cytochrome P450 1B1 (CYP1B1) is highly expressed in a variety of tumors and implicated to drug resistance. More and more researches have suggested that CYP1B1 is a new target for cancer prevention and therapy. Various CYP1B1 inhibitors with a rigid polycyclic skeleton have been developed, such as flavonoids, trans-stilbenes, and quinazolines. To obtain a new class of CYP1B1 inhibitors, we designed and synthesized a series of bentranil analogues, moreover, IC₅₀ determinations were performed for CYP1B1 inhibition of five of these compounds and found that 6o and 6q were the best inhibitors, with IC₅₀ values in the nM range. The selectivity index (SI) of CYP1B1 over CYP1A1 and CYP1A2 was 30-fold higher than that of α-naphthoflavone (ANF). The molecular docking results showed that compound 6q fitted better into the CYP1B1 binding site than other compounds, which was consistent with our experimental results. On the basis of 6o and 6q, it is expected to develop CYP1B1 inhibitors with stronger affinity, higher selectivity and better solubility.

Discovery of structural diverse reversible BTK inhibitors utilized to develop a novel in vivo CD69 and CD86 PK/PD mouse model

For the past two decades, BTK a tyrosine kinase and member of the Tec family has been a drug target of significant interest due to its potential to selectively treat various B cell-mediated diseases such as CLL, MCL, RA, and MS. Owning to the challenges encountered in identifying drug candidates exhibiting the potency block B cell activation via BTK inhibition, the pharmaceutical industry has relied on the use of covalent/irreversible inhibitors to address this unmet medical need. Herein, we describe a medicinal chemistry campaign to identify structurally diverse reversible BTK inhibitors originating from HITS identified using a fragment base screen. The leads were optimized to improve the potency and in vivo ADME properties resulting in a structurally distinct chemical series used to develop and validate a novel in vivo CD69 and CD86 PD assay in rodents.

Novel imidazo[1,5-a]quinoxaline derivatives: SAR, selectivity and modeling challenges en route to the identification of an α5-GABAA receptor NAM

Initial optimization of a series of novel imidazo[1,5-a]quinoxaline compounds originated from a heuristic approach combining two known structural moieties towards α5-GABA_A receptor is shown. This work reveals one-digit nanomolar active compounds as well as positive and negative allosteric modulators resulted from our exploratory approach. To deepen our understanding, their diverse mechanistic nature resulted from in silico modeling is also disclosed.

Mechanism and Origins of Diastereo- and Regioselectivities of Palladium-Catalyzed Remote Diborylative Cyclization of Dienes via Chain-Walking Strategy

Density functional theory calculations have been performed to investigate the palladium-catalyzed remote diborylative cyclization of dienes. The computations reveal that the reaction proceeds through a rarely explored Pd(II)/Pd(IV) catalytic cycle, and the formal σ-bond metathesis between the alkylpalladium intermediate and B₂ pin₂ occurs via the pathway of the B-B oxidative addition/C-B reductive elimination involving the high-valent Pd(IV) species. The diastereoselectivity is determined by the migratory insertion into the Pd-C bond, which is mainly due to the combination of the torsional strain effect, steric repulsion and C-H-O hydrogen-bonding interaction. The steric hindrance around the reacting carbon group in the C-B reductive elimination turns out to be a key factor to provide the driving force of the chain walking of the Pd center to the terminal primary carbon position, enabling the experimentally observed remote regioselectivity.

A Highly Sensitive and Selective Fluorescent Probe for the Detection of Cerium(III) Using Tridentate Based-Oxazolidine: Experimental and DFT Investigations

A new fluorescent sensor based on oxazolidine derivative, (2-(pyridin-2-yl)oxazolidine-4,4-diyl)dimethanol; TN), was designed and synthesized successfully in high yield (82%) under Schiff base reaction. The structural elucidation of the sensor has been confirmed by Infrared Spectroscopy, Nuclear Magnetic Resonance Spectroscopy, and High Resolution Mass Spectrometry - Electrospray Ionization - Time of Flight. The designed TN sensor exhibited high sensitivity and selectivity towards an aqueous solution of cerium(III) over various metal ions under biologically relevant conditions (100.0 mM HEPES buffer pH 7.4). The limit of detection (LOD) was reported as 54.0 nM. The geometry of tridentate based-oxazolidine (TN) and its coordination of cerium(III) (TN-Ce³⁺) was proven by using the density functional theory (DFT) calculations. The highest occupied molecular orbital - lowest unoccupied molecular orbital energy gap was decreased when TN-Ce³⁺ is formed. The results indicated that TN can be used as a fluorescent probe for high sensitivity and selectivity detection of cerium(III) ions.

Improved Selectivity in 7 T Digit Mapping Using VASO-CBV

Functional magnetic resonance imaging (fMRI) at Ultra-high field (UHF, ≥ 7 T) benefits from significant gains in the BOLD contrast-to-noise ratio (CNR) and temporal signal-to-noise ratio (tSNR) compared to conventional field strengths (3 T). Although these improvements enabled researchers to study the human brain to unprecedented spatial resolution, the blood pooling effect reduces the spatial specificity of the widely-used gradient-echo BOLD acquisitions. In this context, vascular space occupancy (VASO-CBV) imaging may be advantageous since it is proposed to have a higher spatial specificity than BOLD. We hypothesized that the assumed higher specificity of VASO-CBV imaging would translate to reduced overlap in fine-scale digit representation maps compared to BOLD-based digit maps. We used sub-millimeter resolution VASO fMRI at 7 T to map VASO-CBV and BOLD responses simultaneously in the motor and somatosensory cortices during individual finger movement tasks. We assessed the cortical overlap in different ways, first by calculating similarity coefficient metrics (DICE and Jaccard) and second by calculating selectivity measures. In addition, we demonstrate a consistent topographical organization of the targeted digit representations (thumb-index-little finger) in the motor areas. We show that the VASO-CBV responses yielded less overlap between the digit clusters than BOLD, and other selectivity measures were higher for VASO-CBV too. In summary, these results were consistent across metrics and participants, confirming the higher spatial specificity of VASO-CBV compared to BOLD.

Peptides as Baits for the Coprecipitation of SH2 Domain-Containing Proteins

Phosphotyrosine (pTyr)-containing amino acid sequences have regulatory effects on proteins that contain pTyr recognition motifs, such as Src Homology 2 (SH2) domains. Using pTyr-containing peptides as a bait for coprecipitation, by immobilization of the synthesized phosphopeptides to beads and incubation with cell lysates, enables to study the binding preference of the SH2 domain for the specific pTyr-sequence obtained from a pTyr-containing protein in a complex biological environment. Using phosphopeptides allows to not only assess the wild-type sequence, but also peptides that can contain modified sequences which carry a nonhydrolyzable pTyr or other modifications varying the binding strength and selectivity, for example, to create strong SH2 domain binders to inhibit their interaction with pTyr-containing proteins. This pulldown experiment can be used as an assay to evaluate the ability of a peptide to bind to the protein of interest in the cell lysate or investigate the selectivity of the peptide. Therefore, immobilizing phosphopeptides and using them as a pulldown tool has a wide range of applications.

Selective removal of Hg(II) by UiO-66-NH2 modified by 4-quinolinecarboxaldehyde: from experiment to mechanism

In wastewater, heavy metal Hg causes serious harm to ecology, so it needs to be removed. In this paper, a novel MOF adsorbent (UiO-66-QU) was prepared by modifying UiO-66-NH₂ with 4-quinolinecarboxaldehyde, which was used to selectively remove Hg(II) from water. The adsorbent was characterized using Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), zeta potentiometer, and X-ray photoelectron spectroscopy (XPS). In order to investigate the Hg(II) adsorption performance of UiO-66-QU, the effect of time, initial concentration, pH, and temperature were carried out. Langmuir model fitting shows that the maximum adsorption capacity of UiO-66-QU for Hg(II) is 556 mg/g at 298 K. The experimental results show that UiO-66-QU has better Hg(II) adsorption capacity than UiO-66-NH₂. The isotherm is in accordance with pseudo-second-order models. It is indicated that the adsorption process is mainly monolayer chemical adsorption. The thermodynamic parameters also indicate that the adsorption process is spontaneous and endothermic. It has excellent reusability and selectivity. XPS and the zeta potential showed that the adsorption mechanism was the complex reaction of Hg(II) with nitrogenous group. Therefore, the adsorbent has potential application prospects in removal of Hg(II) from wastewater.

Evaluation of Small-Molecule HDAC Inhibitors Through In Vitro and In Cellulo Approaches

The aberrant activity of histone deacetylases (HDACs) across a broad range of cancers and other disease indications has led to the development of small-molecule inhibitors that target one or more members of the HDAC protein family. Emerging HDAC inhibitors that show promise in drug discovery programs must be assessed across a range of in vitro assays to establish an inhibitor profile for potency and cellular selectivity towards target HDAC(s) as well as preliminary absorption, distribution, metabolism, and excretion (ADME) features. Here we provide an overview of methods to determine a subset of pivotal in vitro drug-like parameters for HDAC inhibitors (HDACi). We initially describe protocols for parallel artificial membrane permeability assays (PAMPA) to evaluate the passive permeability of small molecules across lipid membranes. Subsequently, we elaborate on cytotoxicity assays using CellTiter-Blue to determine HDACi-induced cell death in healthy/diseased cellular models. We next focus on assessing the target engagement of inhibitors with the appropriate HDAC isoforms in a cellular environment via Western blotting of acetylated HDAC substrates. Finally, we provide detailed guidelines on how to assess the metabolic stability of HDACi through whole blood stability assays. Collectively, these assays provide an overview of the permeability, selectivity, and stability of the HDAC inhibitor under development.

Identification of potent and selective inhibitors of PKR via virtual screening and traditional design

Protein Kinase RNA-activated (PKR) inhibition is thought to be relevant for immunology due to the potential to reduce macrophage and dendritic cell responses to bacteria and its signaling downstream of TNFα. PKR is also associated with neuroscience indications such as Alzheimer's disease due to its activation by the double stranded DNA (dsDNA) virus HSV1, a virus suggested to be important in the development of AD. Studies exploring the mechanistic role of PKR with existing tool molecules such as the tricyclic oxindole C16 are clouded by the poor selectivity profile of this ATP-competitive, Type I kinase inhibitor. Type II kinase leads such as the benzothiophene or pyrazolopyrimidine scaffolds from literature are equally poor in their selectivity profiles. As such, it became necessary to identify more potent and selective chemical matter to better understand PKR biology. A dual approach was taken. The first step of the strategy included virtual screening of the AbbVie compound collection. A combination of pharmacophore-based and GPU shape-based screening was pursued to identify selective chemical matter from promiscuous leads. The second step of the strategy followed traditional compound design. This step initiated from a literature lead with PKR cross reactivity. Combined, the two parallel efforts led to identification of more selective leads for investigation of PKR biology.

Synthesis and in vitro biological evaluation of 3-ethyl-1,5-naphthyridin-2(1H)-one derivatives as potent PARP-1 selective inhibitors and PARP-1 DNA trappers

Inhibition of poly (ADP-ribose) polymerase (PARP) has been applied with great success in the clinical treatment of homologous recombination-deficient malignancy. Recent study demonstrated that not only PARP-1 inhibition but also DNA trapping contributes to the efficacy in BRCA mutant tumors and the toxicities results from the poor selectivity of PARP-1 over PARP-2 as well as their DNA trapping. Herein, a series of 3-ethyl-1,5-naphthyridin-2(1H)-one derivatives (7a-7l, 8a-8n) were synthesized and identified as PARP-1 selective inhibitors and PARP-1 DNA trappers. Among them, compound 8m was found to be highly potent and selective. It inhibited PARP-1 activity and BRCA mutant DLD-1 cell activity with IC₅₀ values of 0.49 nM and 4.82 nM, and the in vitro DNA trapping efficacy of compound 8m was 1.85 nM. Compared with AZD5305, compound 8m significantly improved the selectivity of PARP-1 over PARP-2 as well. Compound 8m was>1000-fold selective for PARP-1 DNA trapping over PARP-2.

Adenine imprinted beads as a novel selective extracellular DNA extraction method reveals underestimated prevalence of extracellular antibiotic resistance genes in various environments

Despite severe threats of extracellular antibiotic resistance genes (eARGs) towards public health in various environments, advanced studies have been hindered mainly by ineffective extracellular DNA (exDNA) extraction methods, which is challenged by trace levels of exDNA and inference from abundant coexisting compounds. This study developed a highly selective exDNA extraction method based on molecular imprinting technology (MIT) by using adenine as the template for the first time. Results suggested that adenine imprinted beads were rough spheres at an average size of 0.39 ± 0.07 μm. They effectively adsorbed DNA in the absence of chaotropic agents, with superior capacity (796.2 mg/g), rate (0.0066/s) and regarding DNA of variable lengths, even the ultra-short DNA (<100 bp). They were also highly selective towards DNA, circumventing the interference of competitive compounds' interference. These properties contribute to efficient exDNA extraction (71 %-119 %) from various environmental samples. Specifically, adenine imprinted beads enabled significantly higher extraction rates of eARGs from river, air and vegetable samples (69 %-95 %) compared to that by commercial DNA extraction products (16 %-62 %). The adenine imprinted beads-based method reveals underestimated eARG levels in the environment and the corresponding risks, and thus will thus be a powerful tool for advanced exDNA research.

Electric field-enhanced coupled with metal-free peroxymonosulfate activactor: The selective oxidation of nonradical species-dominated system

Nowadays metal-free persulfate-based advanced oxidation processes (AOPs) have been intensively investigated, however, the catalysts are often too complex to fully consider their application potential. Conventional AOPs usually suffer from severe interference in real water matrix, thus, selective oxidation is practically and scientifically challenging as it could avoid unnecessary inputs of energy and possible secondary pollutants. In this study, a remarkably synergistic effect was achieved when conventional amorphous boron/peroxymonosulfate (Boron/PMS, 0.67 × 10^-2 min^-1) system was combined with electrolysis (E-Boron/PMS, 1.54 × 10^-2 min^-1) to degrade sulfamethoxazole (SMX). Evidenced by selectively quenching tests with kinetic evaluation, electron paramagnetic resonance (EPR), solvent-exchange experiment and electrochemical analysis, the dominated reactive oxygen species in E-Boron/PMS system tended to be ¹O₂, instead of the ^•OH and SO₄^•-. Mechanistic study unveiled that ¹O₂ was generated via accelerated PMS self-decomposition, triggered by interface alkalization and hydroxyl radicals transfer at the cathode interface. ¹O₂ is considered to be selective to the electron-rich organic compounds, thus E-Boron/PMS system was superior to conventional radical-dominated system (Boron/PMS) for SMX removal in the co-presence of common inorganic anions, showing the great merits of selective oxidation in nonradical system. These findings provided new insights into effective and selective oxidation of SMX via E-Boron/PMS system, which shed new light on the development of nonradical system.

Running capacity in children with bilateral cerebral palsy: What are the biomechanical and neuromotor differences between runners and walkers?

BACKGROUND

Running is a high-level locomotor activity requiring more from joints, muscles and a more complex interaction of the neuromuscular system than walking. High-level locomotor activity has the potential to shed light on motor function deficits that lower-level activity does not reveal. Therefore, the study aimed to compare biomechanical and neuromotor function between a group of children with bilateral cerebral palsy who are able and unable to run.

METHODS

Retrospectively, children with bilateral cerebral palsy aged between 6 and 18 years who completed a clinical gait analysis between 2006 and 2019 were included. Participants were categorized as walkers or runners based on the presence of a double floating phase. Spasticity, selectivity, muscle weakness, and passive range of motion of the lower limbs were measured and dichotomized as «normal» or «abnormal» based on reference values. Functional tasks reflecting balance (standing on one leg) and power (single leg and two-legged jumps) were realized and evaluated as failure or success.

FINDINGS

75 children with bilateral cerebral palsy (53 runners/22 walkers) were included. Children classified as runners were stronger (hip flexors, p = 0.006; hip abductors, p = 0.022; knee flexors, p = 0.001; dorsiflexors, p = 0.014), had greater selectivity (hip flexors, p = 0.011; dorsiflexors, p = 0.001; plantiflexors, p = 0.043) and lower spasticity at the knee extensors (p = 0.045). No differences were observed in the passive range of motion between the two groups. Children classified as runners performed better at all tasks of balance and power (p < 0.05).

INTERPRETATION

Flexors muscles strength and selectivity and knee extensor spasticity are key points for running ability in children with bilateral cerebral palsy.

Competitive removal mechanism to simultaneously incarcerate bisphenol A, triclosan and 4-tert-octylphenol within beta-cyclodextrin crosslinked citric acid used for encapsulation in polypropylene membrane protected-micro-solid-phase extraction

Endocrine disrupting compounds (EDCs) are extensively found in the environment and severely impacting human health. In addressing this issue, the beta-cyclodextrin crosslinked citric acid (BCD-CA) had been previously employed in membrane-protected micro-solid phase extraction for sequestering EDCs from water medium; and the findings revealed that BCD-CA possessed a selectivity property. On that account, the potential of BCD-CA towards competitive adsorption of selected EDCs was investigated in terms of adsorption mechanism and selectivity property. Factors that affected the removal efficiencies such as sample pH, sorbent dosage, contact time and initial concentration were evaluated. The characterization results revealed that the carbon percentage of BCD-CA had increased by 2.04%, while the hydrogen percentage had reduced by 1.83%, signifying the successful crosslinking of BCD-CA. Besides, the amount of active BCD was calculated to be 3.2 × 10^-7 mol, while the amount of carboxyl group was 2.48 × 10^-5 mol per 4 mg of BCD-CA. Moreover, BCD-CA was stable in an aqueous medium with the zeta potential obtained at -36.5 mV and had a high-water retention capacity (∼150%). The competitive adsorption mechanism by BCD-CA with EDCs followed the pseudo-second-order kinetics and Freundlich isotherm, suggesting that the adsorption process was dominated by chemisorption on the heterogeneous surface of the adsorbent. Thermodynamic results revealed that adsorption of 4-tert-octylphenol had the most negative ΔG value, indicating most favorable to be adsorbed by BCD-CA as opposed to triclosan and bisphenol A, which was coherent with the apparent formation constant results. These unique properties manifested the practicality of BCD-CA as a selective adsorbent to detect and remove EDCs from the water medium.

Behavioral and fMRI evidence that arousal enhances bottom-up selectivity in young but not older adults

The locus coeruleus-noradrenergic system integrates signals about arousal states throughout the brain and helps coordinate cognitive selectivity. However, age-related changes in this system may impact how arousal coordinates selectivity in older adults. To examine this, we compared how increases in emotional arousal modulates cognitive selectivity for images differing in perceptual salience in young and older adults. Using functional magnetic resonance imaging, we found that relative to older adults, hearing an arousing sound enhanced young adults' bottom-up processing and incidental memory for high versus low salience category-selective body images. We also examined how arousing sounds impacted a top-down goal to detect dot-probes that appeared immediately after high or low salience images. We found that young adults were slower to detect probes appearing after high salience body images on arousing trials, whereas older adults showed this pattern on non-arousing trials. Taken together, our findings show that arousal's effect on selectivity changes with age and differs across bottom-up and top-down processing.

Boosting the Performance of Nanofiltration Membranes in Removing Organic Micropollutants: Trade-Off Effect, Strategy Evaluation, and Prospective Development

In view of the high risks brought about by organic micropollutants (OMPs), nanofiltration (NF) processes have been playing a vital role in advanced water and wastewater treatment, owing to the high membrane performance in rejection of OMPs, permeation of water, and passage of mineral salts. Though numerous studies have been devoted to evaluating and technically enhancing membrane performance in removing various OMPs, the trade-off effect between water permeance and water/OMP selectivity for state-of-the-art membranes remains far from being understood. Knowledge of this effect is significant for comparing and guiding membrane development works toward cost-efficient OMP removal. In this work, we comprehensively assessed the performance of 88 NF membranes, commercialized or newly developed, based on their water permeance and OMP rejection data published in the literature. The effectiveness and underlying mechanisms of various modification methods in tailoring properties and in turn performance of the mainstream polyamide (PA) thin-film composite (TFC) membranes were quantitatively analyzed. The trade-off effect was demonstrated by the abundant data from both experimental measurements and machine learning-based prediction. On this basis, the advancement of novel membranes was benchmarked by the performance upper-bound revealed by commercial membranes and lab-made PA membranes. We also assessed the potentials of current NF membranes in selectively separating OMPs from inorganic salts and identified the future research perspectives to achieve further enhancement in OMP removal and salt/OMP selectivity of NF membranes.

In silico selectivity modeling of pyridine and pyrimidine based CYP11B1 and CYP11B2 inhibitors: A case study

DESIGN

of selective drug candidates for highly structural similar targets is a challenging task for researchers. The main objective of this study was to explore the selectivity modeling of pyridine and pyrimidine scaffold towards the highly homologous targets CYP11B1 and CYP11B2 enzymes by in silico (Molecular docking and QSAR) approaches. In this regard, a big dataset (n = 228) of CYP11B1 and CYP11B2 inhibitors were gathered and classified based on heterocyclic ring and the exhaustive analysis was carried out for pyridine and pyrimidinescaffolds. The LibDock algorithm was used to explore the binding pattern, screening, and identify the structural feature responsible for the selectivity of the ligands towards the studied targets. Finally, QSAR analysis was done to explore the correlation between various binding parameters and structural features responsible for the inhibitory activity and selectivity of the ligands in a quantitative way. The docking and QSAR analysis clearly revealed and distinguished the importance of structural features, functional groups attached for CYP11B2 and CYP11B1 selectivity for pyridine and pyrimidine analogs. Additionally, the docking analysis highlighted the differentiating amino acids residues for selectivity for ligands for each of the enzymes. The results obtained from this research work will be helpful in designing the selective CYP11B1/CYP11B2 inhibitors.

New ternary Fe(III)-8-hydroxyquinoline-reduced Schiff base complexes as selective anticancer drug candidates

Due to the growing prevalence of cancer diseases, new therapeutic options are urgently needed, and drugs based on metal ions other than platinum are alternatives with exciting possibilities. We report the synthesis, characterization and biological effect of mixed-ligand Fe(III)-aminophenolate complexes derived from salicylaldehyde and L-tryptophan with quinoline derivatives as co-ligands, namely 8-hydroxyquinoline (8HQ), [Fe(L)(8HQ)(H₂O)] (1) and its 5-cloro derivative (Cl8HQ), [Fe(L)(Cl8HQ)(H₂O)] (2). The complex bearing the aminophenolate and lacking the quinoline co-ligand, [Fe(L)(Cl)(H₂O)₂] (3), was prepared for comparison. The analytical and spectroscopic characterization revealed that 1 and 2 are octahedral Fe(III) complexes with the aminophenolate acting as a dianionic tridentate ligand and 8HQ co-ligands as bidentate chelates. Spectroscopic techniques and molecular docking studies were used to evaluate the ability of these complexes to bind bovine serum albumin (BSA) and calf thymus DNA. Complex 2 [Fe(L)(Cl8HQ)(H₂O)] was the one showing higher affinity for both biomolecules. Cell viability was assessed in breast, colorectal and bone human cancer cell lines. 1 and 2 were found to be more active than cisplatin in all cell lines tested. A non-tumoral fibroblast line (L929, mouse non-tumoral fibroblasts) was used to evaluate selectivity. The results evidence that 2 shows much higher selectivity than 1 in all cell lines tested, but particularly in bone cancer cells in which selectivity index (SI) values are 8.0 and 18.8 for 1 and 2, respectively.

Mild and Chemoselective Carboxylic Acid Reduction Promoted by Borane Catalysis

Although considerable advances have been made in developing chemoselective transformations of ubiquitous carboxylic acid groups, many challenges still exist. For instance, their selective reduction is problematic if both more nucleophilic and more electrophilic groups are present in the starting material. Here, we address this problem with a simple and mild protocol using bench-stable reagents at ambient temperatures. This platform is able to tolerate a diverse range of functionality, leaving ketones, esters, nitro-groups, olefins, nitriles and amides untouched. A combination of experimental and computational mechanistic experiments demonstrate that this reaction proceeds via hidden borane catalysis with small quantities of in situ generated BH₃ playing a key role in the exquisite selectivity that is observed.

Discovery of Benzo[d]imidazole-6-sulfonamides as Bromodomain and Extra-Terminal Domain (BET) Inhibitors with Selectivity for the First Bromodomain

The bromodomain and extra-terminal (BET) family of proteins includes BRD2, BRD3, BRD4, and the testis-specific protein, BRDT, each containing two N-terminal tandem bromodomain (BRD) modules. Potent and selective inhibitors targeting the two bromodomains are required to elucidate their biological role(s), with potential clinical applications. In this study, we designed and synthesized a series of benzimidazole-6-sulfonamides starting from the azobenzene compounds MS436 (7 a) and MS611 (7 b) that exhibited preference for the first (BD1) over the second (BD2) BRD of BET family members. The most-promising compound (9 a) showed good binding potency and improved metabolic stability and selectivity towards BD1 with respect to the parent compounds.

Surface ion-imprinted brewer's spent grain with low template loading for selective uranyl ions adsorption from simulated wastewater

Efficient removal of uranyl ions from wastewater requires excellent selectivity of the adsorbents. Herein, we report a new strategy using a high monomer/template molar ratio of 500:1 to prepare surface ion-imprinted brewer's spent grain (IIP-BSG) for selective U(VI) removal using binary functional monomers (2-hydroxyethyl methacrylate and diethyl vinylphosphonate) with high site accessibility and easy template removal. IIP-BSG exhibits a maximum U(VI) adsorption capacity of 165.7 mg/g, a high selectivity toward U(VI) in the presence of an excess amount of Eu(III) (Eu/U molar ratio = 20), a good tolerance of salinity, and a high reusability. In addition, mechanism studies have revealed electrostatic interaction and a coordination of uranyl ions by carboxyl and phosphoryl groups, the predominant contribution of high-energy (specific) sites during selective adsorption, and internal mass transfer as the rate-controlling step of U(VI) adsorption. Furthermore, IIP-BSG shows great potentials to separate U(VI) from lanthanides in simulated nuclear wastewater (pH₀ = 3.5) and selectively concentrate U(VI) from simulated mine water (pH₀ = 7.1). This study proves that the ion-imprinting effect can be achieved using a very low template amount with reduced production cost and secondary pollution, which benefits large-scale promotion of the ion-imprinted materials for selective uranyl ions removal.

Plant volatile compound methyl benzoate is highly effective against Spodoptera frugiperda and safe to non-target organisms as an eco-friendly botanical-insecticide

Recent studies have indicated that the plant volatile methyl benzoate (MB) exhibits significant insecticidal bioactivity against several common insects. However, the potential environmental hazards of MB and its safety to non-target organisms is poorly understood. In the present study, these characteristics were investigated through laboratory experiments and field investigations. The results revealed that MB was highly toxic to the agricultural pest, fall armyworm Spodoptera frugiperda. Compared with the commercial pesticide lambda-cyhalothrin, the toxicities of MB against S. frugiperda larvae and adults were comparable and 3.41 times higher, respectively. Behavioral bioassays showed that the percentage repellency of MB to S. frugiperda larvae was 56.72 %, and MB induced 69.40 % oviposition deterrence rate in S. frugiperda female adults. Furthermore, in terms of median lethal concentration (LC₅₀) and median lethal doses (LD₅₀), MB exhibited non-toxic effects on non-target animals with 3-d LC₅₀ of > 1 % to natural predators (Coccinella septempunctata and Harmonia axyridis), 3-d LD₅₀ of 467.86 µg/bee to the bumblebee Bombus terrestris, 14-d LC₅₀ of 971.09 mg/kg to the earthworm Eisenia fetida, and 4-d LC₅₀ of 47.30 mg/L to the zebrafish Brachydanio rerio. The accumulation of MB in the soil and earthworms was found to be extremely limited. Our comparative study clearly demonstrated that MB is effective as a selective botanical pesticide against S. frugiperda and it is safe to use in the tested environment, with no toxic effects on non-target animals and natural predators.

Zn-Sb Bimetallic Electrocatalyst Enhances the Conversion of CO2 to Formate

Bimetallic Zn-Sb nanoparticles supported on carbon nanotubes can electrocatalyze CO2 into formate efficiently was discovered for the first time, which is the best performance to date for Sb based catalyst under the moderate overpotential. This project was accomplished by a versatile two-step alcoholysis precipitation strategy with the tunable Zn:Sb ratios, and the performance of optimized Zn2.33Sb0.67O4 was locked in the electrochemical CO2 reduction reaction. During the subsequent electrolysis, the mixed phases of metallic Zn and Sb served as active centers. Zn-Sb heterostructure and the electron relocation were confirmed. By means of interactions and possible additional binding sites for reaction intermediate *OCHO, the material manifested the different catalytic properties from either Zn or Sb and selective for formate up to 92%, which was ca. 6.1 times or 4.6 times than that of each single component. The encouraging results highlighted the power of the interaction between binary metallic component to synergistically electrocatalyze CO2 conversion.

Water-compatible Janus molecularly imprinted particles with mouth-like opening: Rapid removal of pharmaceuticals from hospital effluents

Pharmaceuticals in hospital effluents, often discharged into the public sewage network without sufficient treatment, have shown negative impacts to the human health and aquatic environment. However, the conventional adsorbents used to remove these micropollutants had several deficiencies, including slow uptake kinetics and poor selectivity. To overcome these challenges, water-compatible Janus MIP particles (J-MIPs) with mouth-like openings were synthesized using seeded interfacial polymerization in this work. Among the series of J-MIPs, the selected J-MIP₃ showed fast binding kinetics (∼40 s) towards the target pollutant. The theoretical and instrumental analysis suggested that the electrostatic interaction, hydrogen bond and hydrophobic reaction constituted the dominant mechanism for J-MIP₃'s recognition of target pharmaceutical. Selectivity and robustness tests indicated that the synthetic method was promising in practical application. Finally, the feasibility of the J-MIP₃ fixed-bed column in the rapid removal of propranolol (PRO) from hospital effluents was successfully demonstrated. Compared to the activated carbon fixed-bed column, the J-MIP₃ fixed-bed column showed at least 7-fold enhancement in its treatment efficiency. To the best of our knowledge, this is the first time that the accelerated mass transfer and fast removal of the pharmaceutical from wastewater have been achieved by the synthetic receptor with asymmetric structure. We believe the present study will open new avenues for the development of multi-functional molecularly imprinted polymers as well as Janus materials in environmental science.

Phosphorus Tailors the d-Band Center of Copper Atomic Sites for Efficient CO2 Photoreduction under Visible-Light Irradiation

Photoreduction of CO₂ into solar fuels has received great interest, but suffers from low catalytic efficiency and poor selectivity. Herein, two single-Cu-atom catalysts with unique Cu configurations in phosphorus-doped carbon nitride (PCN), namely, Cu₁ N₃ @PCN and Cu₁ P₃ @PCN were fabricated via selective phosphidation, and tested in visible light-driven CO₂ reduction by H₂ O without sacrificial agents. Cu₁ N₃ @PCN was exclusively active for CO production with a rate of 49.8 μmol_CO  g_cat ^-1  h^-1 , outperforming most polymeric carbon nitride (C₃ N₄ ) based catalysts, while Cu₁ P₃ @PCN preferably yielded H₂ . Experimental and theoretical analysis suggested that doping P in C₃ N₄ by replacing a corner C atom upshifted the d-band center of Cu in Cu₁ N₃ @PCN close to the Fermi level, which boosted the adsorption and activation of CO₂ on Cu₁ N₃ , making Cu₁ N₃ @PCN efficiently convert CO₂ to CO. In contrast, Cu₁ P₃ @PCN with a much lower Cu 3d electron energy exhibited negligible CO₂ adsorption, thereby preferring H₂ formation via photocatalytic H₂ O splitting.

Selective monitoring of natural gas sulphur-based odorant mixture of t-butyl mercaptan and methyl ethyl sulphide using an array of microfluidic gas sensors

A natural gas (NG) odorization system requires continuous monitoring as well as an optimal injection to satisfy the odorization guidelines, minimize over-odorization, and prevent hazardous gas leaks. NG consists of hydrocarbons such as methane, odorants such as tert-butyl mercaptan, and other sulphur-based VOCs such as hydrogen sulphide; therefore, selectivity is paramount for the reliable and accurate monitoring of odorants. In this study, we developed a portable device integrated with an array of five different sensors to detect a mixture of tert-butyl mercaptan and methyl ethyl sulphide for a concentration range of 1 ppm to 10 ppm. A machine learning model was developed to predict the presence and concentration of NG odorants from the sensor data. The best-performing sensors in the array achieved high sensitivity and selectivity indicators (measured using the Davies-Bouldin index) of 0.3667 (1⁄ppm) and 0.125, respectively. The sensor system achieved a classification accuracy of 98.75% between NG odorants and hydrogen sulphide, with an overall Mean Squared Error (MSE) and R² error (for the regression model) of 0.50 and 95.16%. These results indicate that the developed portable device and the machine learning model have promising applications for the selective monitoring of NG odorants.

Discovery of selective HDAC6 inhibitors capped by flavonoid or flavonoid-analogous moieties as anti-cancer therapeutics simultaneously harboring anti-proliferative and immunomodulatory activities

Specific HDAC6 inhibitors (HDAC6is) simultaneously harboring anti-proliferative and immunomodulatory properties may prohibit tumor progression via intrinsic and immune driven effects. Herein, built upon the structurally novel lead TFH-7, structure-activity relationship study culminated in the identification of azaflavone-capped compound 20, which exhibited comparable HDAC6 inhibitory activity (IC₅₀ = 8.5 nM) to that of Tubastatin A, a highly selective HDAC6i, as well as favorable subtype specificity. Importantly, concurrent with its impressive anti-proliferative efficacy against several solid tumor cell lines, 20 remarkably alleviated the transduction of immune-related STAT3 signaling and attenuated the expression of immunosuppressive checkpoint PD-L1 at submicromolar concentration, highlighting the immunomodulatory properties. Moreover, consistent with its favorable subtype selectivity, 20 displayed low cytotoxicity against normal human umbilical vein endothelial cells, revealing a promising safety profile. Following the intravenous administration, it demonstrated acceptable elimination half-life and exposure in Sprague-Dawley rats. Hence, the extensive functional investigation or structural modification of 20 is valuable.