Nucleic Acid Armor: Fortifying RNA Therapeutics through Delivery and Targeting Innovations for Immunotherapy.

RNA is a promising nucleic acid-based biomolecule for various treatments because of its high efficacy, low toxicity, and the tremendous availability of targeting sequences. Nevertheless, RNA shows instability and has a short half-life in physiological environments such as the bloodstream in the presence of RNAase. Therefore, developing reliable delivery strategies is important for targeting disease sites and maximizing the therapeutic effect of RNA drugs, particularly in the field of immunotherapy. In this mini-review, we highlight two major approaches: (1) delivery vehicles and (2) chemical modifications. Recent advances in delivery vehicles employ nanotechnologies such as lipid-based nanoparticles, viral vectors, and inorganic nanocarriers to precisely target specific cell types to facilitate RNA cellular entry. On the other hand, chemical modification utilizes the alteration of RNA structures via the addition of covalent bonds such as N-acetylgalactosamine or antibodies (antibody-oligonucleotide conjugates) to target specific receptors of cells. The pros and cons of these technologies are enlisted in this review. We aim to review nucleic acid drugs, their delivery systems, targeting strategies, and related chemical modifications. Finally, we express our perspective on the potential combination of RNA-based click chemistry with adoptive cell therapy (e.g., B cells or T cells) to address the issues of short duration and short half-life associated with antibody-oligonucleotide conjugate drugs.

Rapid Synthesis and Microenvironment Optimization of Hierarchical Porous Fe─N─C Catalysts for Enhanced ORR in Microbial Fuel Cells.

Here, an approach to produce a hierarchical porous Fe-N-C@TABOH catalyst with densely accessible high intrinsic active FeNx sites is proposed. The method involves a single-step pyrolysis of Zn/Fe-zeolitic imidazolate framework (Zn/Fe-ZIF-H) with tetrabutylammonium hydroxide (TABOH) micelles, which is obtained by utilizing TABOH as a structural template and electronic mediator at room temperature for a brief duration of 16 min. Notably, the yield of Zn/Fe-ZIF-H is 3.5 times that of Zn/Fe-ZIF-N prepared by conventional method. Results indicate that in addition to expediting synthesis and increasing yield of the Zn/Fe-ZIF-H, the TABOH induces a hierarchical porous structure and fosters the formation of more and higher intrinsic active FeNx moieties in Fex-N-C@TABOH, showing that TABOH is a multifunctional template. Crucially, the increased mesoporosity/external surface area and optimized microenvironment of Fe-N-C@TABOH significantly enhance ORR activity by facilitating the formation of high intrinsic active FeNx sites, increasing accessible FeNx sites, and reducing mass transfer resistance. Through structure tailoring and microenvironment optimization, the resulting Fe-N-C@TABOH exhibits superior ORR performance. DFT calculation further validates that the synergistic effect of these two factors leads to low ORR barrier and optimized *OH adsorption energy. This study underscores the importance of structure and electronic engineering in the development of highly active ORR catalysts.

Heterogeneous Co-Ni phosphide with active sites for water dissociation and efficient hydrogen evolution reaction.

The construction of highly active and stable transition phosphide-based materials is widely regarded as an alternative approach to the use of Pt-based catalysts in the field of electrocatalytic hydrogen evolution. Herein, self-supported heterostructure Co-Ni phosphides (denoted as CoxNi1-x-P) were synthesized with different metal ratios by a low temperature electrodeposition strategy. Impressively, the optimized heterogeneous Co0.5Ni0.5-P nanocomposites displayed outstanding hydrogen evolution performance, with low overpotentials of 67 mV and 181 mV to deliver current densities of 10 mA cm-2 and 100 mA cm-2 in alkaline electrolyte. X-ray photoelectron spectroscopy revealed the optimized electronic structure of Co0.5Ni0.5-P, which led to an improvement in the conductivity. Density functional theory calculations demonstrated that the Co0.5Ni0.5-P heterostructure could provide a more optimal water-dissociation-related Volmer process for hydrogen evolution reaction (HER), in which water molecules could be easily activated on Co0.5Ni0.5-P with a low energy barrier. Moreover, the downshift of the d-band center confirmed the optimized H adsorption, further accelerating the HER kinetics.

Vanadium-induced synthesis of amorphous V-Co-P nanoparticles for an enhanced hydrogen evolution reaction.

The hydrogen evolution reaction (HER) plays a vital role for the production of pure hydrogen with zero carbon release. Developing high efficiency non-noble metal electrocatalysts could reduce its cost. Here, vanadium doped cobalt phosphide grown on carbon cloth (CC) was synthesized by the low temperature electrodeposition-phosphorization method. The influence of V dopants on the structural, morphological, and electrocatalytic performance of Vx-Co1-x-P composites was also investigated in-depth. Impressively, the optimized amorphous V0.1-Co0.9-P nano-electrocatalyst exhibits outstanding catalytic activity with a low overpotential of 50 mV at a current density of 10 mA cm-2 and a small Tafel value of 48.5 mV dec-1 in alkaline media. The results showed that V dopants in the composite change its crystal structure from the crystalline phase to the amorphous phase, resulting in the introduction of V-O sites, which regulate the electron density of the active sites and the exposure of surface active sites and thus promote the electrocatalytic HER process. This work provides a novel idea for the fabrication of high-efficiency metal phosphide based electrocatalysts.

Engineering Hollow Core-Shell N-C@Co/N-C Catalysts with Bits of Ni Doping Used as Efficient Electrocatalysts in Microbial Fuel Cells.

The sluggish and inefficient oxygen reduction reaction (ORR) of cathode catalysts in microbial fuel cells is widely accepted as the key restriction in implementing their large-scale actual production application. Recently, modification of nitrogen-doping carbon materials with some transition metal species (M-N-C) is expected to be reserve force to substitute commercial noble metal catalysts. However, long-term stability is always unable to solve effectively. We report a simple synthetic approach of metal-organic framework-derived hollow core-shell Co-nitrogen codoping-modified porous carbon catalysts (N-C@Co/N-C-n%Ni), which is introduced by bits of Ni substance, via the template method and vacuum-assisted impregnation method that exhibit similar catalytic activity to commercial Pt/C catalysts. The hollow core-shell H-N-C@Co/N-C-3%Ni catalyst shows excellent ORR performance and stability, which is 96.31% of the initial current after 125 h continuous reaction, and has been capable of yielding a maximum power density of 1.17 ± 0.01 W·m-2 with 2% decrease in 45 days for long-term continuous operation.

Ground vibration from freight railway: environmental impact and potential mitigation measure at propagation path.

The freight train-induced vibrations and noise generate increasing environmental problems owing to its heavier axle loads and longer pass-by duration. To develop useful mitigation measures, the vibration characteristic induced by this type of rail transportation needs to be better learned. In the present work, firstly, the in situ measurements were carried out on two railway lines which were used for mixed freight and passenger trains. Both the track vibrations and ground vibrations resulted from different train types were measured and compared. Then, based on the dominant frequencies of ground vibrations from experimental results, the mitigation measure of periodic piles was proposed as a mitigation measure by impeding propagation. The periodic theory of solid-state physics was introduced and three-dimensional (3D) finite element (FE) simulation was employed to analyse the vibration reduction performance of periodic piles, while the attenuation zone (AZ) of the piles was also calculated. The measurement results indicate that the freight train can generate a larger level of vibrations on both the track structure and ground at the near field, especially below 10 Hz. Even though the speed of freight trains is as low as 40-55 km/h, the vibration exposure level (VEL) is higher than normal passenger trains (80-90 km/h) and EMU trains (120 km/h). The simulation results show that the proposed solution of installing periodic piles at the propagation path raises the positive influence on vibration reduction.

Ultrasonic-assisted preparation of highly active Co3O4/MCM-41 adsorbent and its desulfurization performance for low H2S concentration gas.

Co3O4/MCM-41 adsorbents were successfully prepared by ultrasonic assisted impregnation (UAI) and traditional mechanical stirring impregnation (TMI) technologies and characterized by X-ray diffraction (XRD), N2 adsorption desorption, Fourier transform infrared spectra (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and thermogravimetry-differential thermal analysis (TG-DTA). The H2S removal performances for a simulated low H2S concentration gas were investigated in a fixed-bed. The effect of preparation and adsorption conditions on the H2S removal over Co3O4/MCM-41 were systematically examined. The results showed that UAI promotes more and well defined highly dispersed active Co3O4 phase on MCM-41. As compared to the Co3O4/MCM-41-T prepared via TMI, the saturated H2S capacity of Co3O4/MCM-41-U prepared via UAI improved by 33.2%. The desulfurization performance of adsorbents decreased in the order of Co3O4/MCM-41-U > Co3O4/MCM-41-T > MCM-41. The Co3O4/MCM-41-U prepared using Co(NO3)2 concentration of 10%, ultrasonic time of 2 h, calcination temperature of 550 °C and calcination time of 3 h exhibited the best H2S removal efficiency. At adsorption temperature of 25 °C with model gas flowrate of 20 mL min-1, the breakthrough time of Co3O4/MCM-41-U was 10 min, and the saturated H2S capacity and H2S removal rate was 52.6 mg g-1 and 47.8%, respectively.