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Cells have used compartmentalization to implement complex biological processes involving thousands of enzyme cascade reactions. Enzymes are spatially organized into the cellular compartments to carry out specific and efficient reactions in a spatiotemporally controlled manner. These compartments are divided into membrane-bound and membraneless organelles. Mimicking such cellular compartment systems has been a challenge for years. A variety of artificial scaffolds, including liposomes, polymersomes, proteins, nucleic acids, or hybrid materials have been used to construct artificial membrane-bound or membraneless compartments. These artificial compartments may have great potential for applications in biosynthesis, drug delivery, diagnosis and therapeutics, among others. This review first summarizes the typical examples of cellular compartments. In particular, the recent studies on cellular membraneless organelles (biomolecular condensates) are reviewed. We then summarize the recent advances in the construction of artificial compartments using engineered platforms. Finally, we provide our insights into the construction of biomimetic systems and the applications of these systems. This review article provides a timely summary of the relevant perspectives for the future development of artificial compartments, the building blocks for the construction of artificial organelles or cells.

In this work heme models with four [Fe(II)(P)], five [Fe(II)(P)Im], [Fe(II)(P)O₂] and six ligands [Fe(II)(P)(Im)O₂], where P=porphyrin, with different spin states (m_s=5, 3 and 1) of the iron atom were investigated using relativistic-corrected quantum chemistry methods (PW6B95-D3-DKH/jorge-TZP-DKH). Dependence of the iron-ligand bond properties on (i) spin state and (ii) number of ligands were analyzed using natural bond orbital analysis, electron density topology, electrostatic potential and electron localization function. It is shown that reversible binding of O₂ is possible in case of formation of semicoordination bond between Fe(II) and imidazole. Binding of the fifth and sixth ligand from the energetic and orbital points of view is more favorable for the triplet Fe(II) state. At the same time for the six-coordinated complex [Fe(II)(P)(Im)O₂] interconversion of Fe(II) electrons of valent 3d orbital from quintet to triplet and vice versa is possible under thermal fluctuations (energy barriers less than 2 kcal/mol).

The rational design of artificial supramolecular structures with specific properties and functions hinges the comprehensive understanding of the coordination and noncovalent interactions driving self-assembly. Herein, the self-assembly of supramolecular systems through octahedral coordination between Ni(II) ions and a flexible tripeptide was theoretically investigated using quantum chemical calculations. These calculations utilized the B3LYP functional with the polarizable continuum model. Our results indicate that tridentate sites have a greater propensity for coordination, and that the presence of chloride anions and conformational shifts enhance bidentate and monodentate coordination. Insights into the effect of counter anions on the stability of octahedral coordination and the prerequisites for self-assembly were gained by determining the stable conformation and potential reaction pathways of the tripeptide before and after adding chloride anions through an efficient automated conformational search. The formation of intramolecular hydrogen bonding interactions during the conformational changes was also studied using model calculations. Possible processes for initial self-assembly of tripeptide were proposed. This study enhances the fundamental understanding of the conformational behavior of building blocks during supramolecular formation and advance the potential for constructing future bioinspired complexes.

Here we report, synthesis of ferrocenyl based bis(pyrazolyl) palladium complexes. The catalytic utility of the complexes in the cross-coupling of triarylbismuthanes and aryl bromides was evaluated. Our ferrocenyl based palladium complex showed wide substrate scope for both triarylbismuthanes and aryl bromides. Further, the current catalytic system also showed superior activity over the well-established palladium-phosphine catalytic system using triarylbismuthanes as reagents.

In recent years, improving the pharmaceutical properties of drug delivery for anti-cancer treatment has become increasingly important. This is necessary to address challenges related to absorption, distribution, and stability. One potential approach solution is to attach the drug to a carrier system, such as functional noble nanomaterials, in order to improve the control of drug release and stability. Core-satellite nanoparticles (CSN) with an anisotropic morphology have enormous potential for targeted drug delivery and cancer treatment because of their large surface area, exceptional stability, and biocompatibility. We used a simple seed-mediated approach to synthesize urchin-like gold nanoparticles (ULGNPs) with a high aspect ratio and a dense network of 49 nm-sized branches, using seed solution, silver nitrate, and ascorbic acid. The ULGNPs were synthesized without a surfactant and then encapsulated with thin layers of amorphous TiO₂ (ULGNPs@TiO₂), resulting in an average overall size of 136±15 nm with a 27.5 nm TiO₂ layer. Doxorubicin (Dox) was chosen as a model drug to assess the distribution carrier ability of ULGNPs@TiO₂ core-satellite nanoparticles. The results showed 86.5 % Dox loading and 72.3 % release capacity at pH 5. The anti-cancer ability of ULGNPs@TiO₂-Dox was meticulously assessed using breast cancer MCF-7 cells in the WST-1 assay. The results revealed that ULGNPs@TiO₂-Dox exhibited approximately 92 % toxicity in MCF-7 cells compared to the free Dox of 89.6 % at low concentrations (5 ppm). Based on the simulation results for loading ULGNPs@TiO₂ with Dox, it was observed that a structure containing five layers of Au (111) with three fixed bottom layers and two relaxed top layers, in addition to six TiO₂ (100) layers, was analyzed using Grimme's DFT-D3 dispersion corrections (Scheme 1). The density functional theory (DFT) adsorption energy (E_ads) shows that the amorphous TiO₂ increases the Dox loading activity of ULGNPs, with E_ads=-3.85 eV, negatively higher than isolated ULGNPs (E_ads=-2.87 eV) and TiO₂ alone (E_ads=-3.61 eV). This drug carrier design has the potential to revolutionize anti-cancer treatment.

Bis-heterocycles were synthesized via a consecutive one-pot process by a Groebke-Blackburn-Bienaymé reaction (GBB-3CR) followed by Copper-catalyzed Alkyne-Azide Cycloaddition (CuAAC) assisted by alternative sustainable energies (ASE) such as ultrasonic and mechanical. These efficient and convergent strategies allowed the in situ generation of complex azides functionalized with imidazo[1,2-a]pyridines (IMPs), which was used as a synthetic platform. The target molecules contain two privileged scaffolds in medicinal chemistry: IMPs and the heterocyclic bioisostere of trans-amide bond, the 1,4-disubstituted 1H-1,2,3-triazoles (1,4-DS-1,2,3-Ts).

The development of ultrasensitive electronic sensors for in vitro diagnostics is essential for the reliable monitoring of asymptomatic individuals before illness proliferation or progression. These platforms are increasingly valued for their potential to enable timely diagnosis and swift prognosis of infectious or progressive diseases. Typically, the responses from these analytical tools are recorded as digital signals, with electronic data offering simpler processing compared to spectral and optical data. However, preprocessing electronic data from potentiometric biosensor arrays is still in its infancy compared to more established optical technologies. This study utilized the Single-Molecule with a Large Transistor (SiMoT) array, which has achieved a Technology Readiness Level of 5, to explore the impact of data preprocessing on electronic biosensor outcomes. A dataset consisting of plasma and cyst fluid samples from 37 patients with pancreatic precursor cyst lesions was analyzed. The findings revealed that standard signal preprocessing can produce misleading conclusions due to artifacts introduced by mathematical transformations. The study offers strategies to mitigate these effects, ensuring that data interpretation remains accurate and reflective of the underlying biochemical information in the samples.

The synthesis and characterization of a Co/Fe mixed-metal banana-shaped polyoxometalate with the formula [(Co_2.5Fe_0.5(H₂O)PW₉O₃₄)₂(PW₆O₂₆)]^16- (Co₅Fe) is reported. This transition-metal-substituted polyoxometalate readily assembles from its components in a one-pot reaction and crystallizes in the monoclinic space group P2₁/c. The structure of Co₅Fe can be considered a double sandwich composed by two B-α-{Co_2.5Fe_0.5PW₉O₄₀} Keggin units, in which one coordinatively saturated octahedral metal position is equally occupied by Co(II) and Fe(III) ions with a 50 % of site occupancy. These Keggin units are linked via a hexalacunary Keggin unit {PW₆O₂₆}. Single crystal X-ray diffraction and magnetic measurements support the proposed atom arrangement within the crystal structure. Magnetic measurements of these double trimeric unit {Co_2.5Fe_0.5O₁₃}₂ show a combination of antiferromagnetic interactions, the presence of spin frustration, and the first-order spin-orbit coupling of Co(II) ions. Electrocatalytic water oxidation measurements show that Co₅Fe displays low stability in both homogeneous and heterogeneous conditions. This is evidenced by the constant increase on the catalytic currents over time together with the appearance of polyoxometalate-derived electrode-bound species that can be responsible for the observed catalytic activity.

Toussaintia orientalis Verdc. (Annonaceae) is a medicinal plant species endemic to Tanzania. It is classified under the International Union for Conservation of Nature (IUCN) as an extremely endangered species threatened with extinction. The review covers the phytochemistry of this plant species and the pharmacological properties of the compounds obtained therefrom. The chemistry of this plant species entails natural products with different structures including uncommon cinnamoyl tetraketide derivatives, aristolactam alkaloids, and flavonoids. The review identifies 27 compounds belonging to different subclasses of natural products obtained from this species for the past fourteen years (2010-2024). These compounds are discussed along with other 13 related natural products. T. orientalis derived compounds exhibit varied potential pharmacological applications as antibacterial, anticancer, anti-inflammatory, antiviral, and neuroprotective agents. Some of the reported compounds displayed pharmacological properties corroborating the use of this plant species in traditional medicine. This review provides baseline data as one comprehensive compilation that will ignite interest and guide future research and development of therapeutic agents inspired by the chemodiversity presented by this plant species while at the same time attracting the attention of plant conservationists to initiate efforts to conserve this highly endangered biomedical treasure.