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Hyperbranched polyethyleneimine having 25,000 Da molecular weight was functionalized by a simple sulfopropylation reaction, affording a novel N-sulfopropylated PEI derivative (PEI-SO₃ ^-). The successful introduction of N-sulfopropyl and sulfobetaine groups to the amino groups of PEI was spectroscopically confirmed. Furthermore, the antibacterial and anti-cyanobacterial activity of PEI-SO₃ ^- in comparison to the parent PEI were investigated on two type heterotrophic bacteria, i. e., Gram (-) Escherichia coli and Gram (+) Staphylococcus Aureus bacteria, and one type of autotrophic cyanobacterium, i. e. Synechococcus sp. PCC 7942. Both PEI-SO₃ ^- and PEI showed an enhanced, concentration-dependent antibacterial and anti-cyanobacterial activity against the tested bacteria strains, with PEI-SO₃ ^- exhibiting higher activity than the parent PEI, signifying that the introduction of the sulfopropyl and sulfobetaine groups to the PEI amino groups enhanced the antibacterial and the anti-cyanobacterial properties of PEI. In the case of cyanobacteria, PEI-SO₃ ^- was found to affect the integrity of the photosynthetic system by the inhibition of Photosystem-II electron transport activity. Cytocompatibility and hemocompatibility studies revealed that PEI-SO₃ ^- exhibits high biocompatibility, suggesting that PEI-SO₃ ^- could be considered as an attractive antibacterial and anti-cyanobacterial candidate for various applications in the disinfection industry and also against the harmful cyanobacterial blooms.

Crystalline ZIF-8 (C-ZIF-8) and amorphous ZIF-8 (Am-ZIF-8) were prepared and investigated to control the germination of Striga hermonthica, a root parasitic plant, which threatens cereal crops production particularly in sub-Saharan Africa. We have demonstrated that Am-ZIF-8 shows a better performance than C-ZIF-8 in inhibiting Striga seeds germination. This efficient performance of Am-ZIF-8 materials can be attributed to the incomplete deprotonation of 2 methylimidazole (2MIM) during amorphization, leading to the presence of unsaturated Zn-N coordination with the uncoordinated -NH groups available to undergo hydrogen bonding with the strigolactone analog GR24 forming a more stable Am-ZIF-8⋅⋅⋅GR24 hydrogen bonded network. We further established that application of ZIF-8 materials generally has no adverse effects on the growth and quality of rice crops.

Converting CO₂ into high-value chemical fuels through green photoelectrocatalytic reaction path is considered as a potential strategy to solve energy and environmental problems. In this work, BiVO₄/ZIF-8 heterojunctions are prepared by in-situ synthesis of ZIF-8 nanocrystals with unique pore structure on the surface of BiVO₄. The experimental results show that the silkworm pupa-like BiVO₄ is successfully combined with porous ZIF-8, and the introduction of ZIF-8 can provide more sites for CO₂ capture. The optimal composite ratio of 4 : 1-BiVO₄/ZIF-8 exhibits excellent CO₂ reduction activity and the lowest electrochemical transport resistance. In the electrocatalytic system, the formate Faraday efficiency of 4 : 1-BiVO₄/ZIF-8 at -1.0 V vs. RHE is 82.60 %. Furthermore, in the photoelectrocatalytic system, the Faraday efficiency increases to 91.24 % at -0.9 V vs. RHE, which is 10.8 times higher than the pristine BiVO₄. The results show that photoelectric synergism can not only reduce energy consumption, but also improve the Faraday efficiency of formate. In addition, the current density did not decrease during 34 h electrolysis, showing long-term stability. This work highlights the importance of the construction of heterojunction to improve the performance of photoelectrocatalytic CO₂ reduction.

The geometry of hydrogen sulfide was studied by calculating potential energy surface (PES) with over 1800 configurations. The calculations were performed at very accurate CCSD(T)/aug-cc-pvz5 level. The most stable geometry on the PES has bond angle (H-S-H) of 92.40° and bond length (S-H) of 1.338 Å. The PES shows that hydrogen sulfide is a quite flexible molecule. Namely, it can change the bonding angle (H-S-H) in the range of 15.6° (from 84.6° to 100.2°) and the bond lengths (S-H) in the range of 0.082 Å (from 1.299 Å to 1.381 Å) with an energy increase of only 1.0 kcal/mol. An influence of hydrogen sulfide geometry on its hydrogen bonds was studied on several hydrogen sulfide/hydrogen sulfide and water/hydrogen sulfide dimers. It showed that the change of hydrogen sulfide geometry does not influence the strength of hydrogen bond. Fully optimized geometries in gas and water solution phases revealed structural differences of both monomers and dimers in gas phase and water phase. SAPT analysis of the optimized dimer geometries showed that in all the dimers electrostatic is the most dominant contribution, while, in the dimers with hydrogen sulfide, the influence of dispersion contribution becomes quite pronounced.

The excessive use of antibiotic ofloxacin (Oflx) can cause serious detrimental effects to human health. Therefore, the utmost research priority is required to develop facile methods to detect Oflx. Herein, a V-shaped aggregation-induced emission (AIE) active Schiff base SDANA was introduced for the fluorescent turn-on detection of Oflx. The Schiff base SDANA was synthesized by condensing 4,4'-sulfonyldianiline with two equivalents of 2-hydroxy-1-naphthaldehyde. The nearly non-fluorescent SDANA in DMSO showed strong orange emission with the increase in HEPES buffer (H₂O, 10 mM, pH 7.4) fractions in DMSO from 70 %-95 % due to the combined effects of AIE and ESIPT. The DLS and SEM analyses were performed to complement the formation of self-aggregates of SDANA. With the addition of Oflx, the fluorescence emission of AIE luminogen (AIEgen) SDANA (λ_em=575 nm, λ_ex=400 nm) was blue-shifted and enhanced at 530 nm. The interactions of Oflx over the surface of SDANA aggregates disrupted the intramolecular charge transfer and aggregation morphology of SDANA, which gave a distinct fluorescence response to detect Oflx. The detection limit for Oflx was estimated as 0.81 μM, and the developed probe AIEgen SDANA was applied for the quantification of Oflx in human blood serum.

The front cover article describes the recent progress in the field of photocatalytic transformation of organics to valuable chemicals. This comprehensive review highlights how photocatalysis can be involved in selective transformations of organic compounds, including reduction and coupling reactions such as C-C and C-N couplings. By examining intrinsic and extrinsic factors, the authors provide insights into the rational design of efficient and stable photocatalytic systems dedicated to the synthesis of fine chemicals. More details can be found in the Review by Marcin Kobielusz, Wojciech Macyk, and co-workers (DOI: 10.1002/cplu.202400171).