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Major diseases, such as cancer and COVID‐19, are frightening global health problems, and sustained action is necessary to develop vaccines. Here, for the first time, ethoxy acetalated dextran nanoparticles (Ace‐Dex‐NPs) are functionalized with 9‐N‐(4H‐thieno[3,2‐c]chromene‐2‐carbamoyl)‐Siaα2−3Galβ1−4GlcNAc (TCCSia‐LacNAc) targeting macrophages as a universal vaccine design platform. First, azide‐containing oxidized Ace‐Dex‐NPs are synthesized. After the NPs are conjugated with ovalbumin (OVA) and resiquimod (Rd), they are coupled to TCCSia‐LacNAc‐DBCO to produce TCCSia‐Ace‐Dex‐OVA‐Rd, which induce a potent, long‐lasting OVA‐specific cytotoxic T‐lymphocyte (CTL) response and high anti‐OVA IgG, providing mice with superior protection against tumors. Next, this strategy is exploited to develop vaccines against infection by severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2). The receptor‐binding domain (RBD) of the SARS‐CoV‐2 spike protein is the main target for neutralizing antibodies. The TCCSia‐Ace‐Dex platform is preferentially used for designing an RBD‐based vaccine. Strikingly, the synthetic TCCSia‐Ace‐Dex‐RBD‐Rd elicited potent RBD‐neutralizing antibodies against live SARS‐CoV‐2 infected Vero E6 cells. To develop a universal SARS‐CoV‐2 vaccine, the TCCSia‐Ace‐Dex‐N‐Rd vaccine carrying SARS‐CoV‐2 nucleocapsid protein (N) is also prepared, which is highly conserved among SARS‐CoV‐2 and its variants of concern (VOCs), including Omicron (BA.1 to BA.5); this vaccine can trigger strong N‐specific CTL responses against target cells infected with SARS‐CoV‐2 and its VOCs. [ABSTRACT FROM AUTHOR]

It is challenging to identify the optimal metal–organic framework (MOF) adsorbents for gas adsorption and membrane-based separation from the large-scale material databases. The high-throughput computational screening (HTCS) method was adopted to discover the optimal materials for CO2/H2 separation from thousands of MOFs. First, a hierarchical strategy was used to select 1092 MOFs from 13 512 MOFs, and their adsorption capacity towards the equimolar CO2/H2 mixture at 298 K and 10 bar was further calculated using the grand canonical Monte Carlo (GCMC) simulations. The results show that those MOFs with lvtb topology and organic linker 1,2,4,5-tetrazine are conducive to exhibiting high performance CO2/H2 adsorption separation among top-100 MOFs with high performance. The MOFs with pore limited diameter (PLD), largest cavity diameter (LCD), gravimetrical surface area (GSA), and void fraction in the range of 4–12 Å, 5–12 Å, 5500–6500 m2 g−1 and 0.80–0.85, respectively, have high adsorption capacity towards CO2. Second, the dynamic adsorption properties of the top-4 MOFs were simulated by the breakthrough curves of the binary (CO2/H2) and quinary (CO2/H2/CH4/CO/N2) mixtures in the fixed adsorption bed. MOF-4641 exhibits a high breakthrough time of 130 for the quinary mixture. Finally, the adsorption mechanism of CO2 in the top-4 MOFs was investigated by the radial distribution function (RDF), the mass center probability density distribution, etc. The atomic insights from HTCS and breakthrough curve predictions in this work will be helpful in developing novel porous materials and obtaining superior CO2 separation performance. [ABSTRACT FROM AUTHOR]

The capture and storage of toxic industrial chemicals such as H2S using porous polymer networks (PPNs) has shown promising application because of their high porosity, high surface area, high stability, low‐cost and lightweight. In this work, 17,846 PPNs with the diamond‐like topology were computationally screened to identify the optimal adsorbents for the removal of H2S and CO2 from humid natural gas based on the combination of molecular simulation and machine learning algorithms. The top‐performing PPNs such as hPAFs‐0201 with the highest adsorption performance scores (APS) were evaluated and identified based on their adsorption capacities and selectivity for H2S and CO2. The strong affinity between water molecules and the framework atoms in a few PPNs has a significant impact on the adsorption selectivity of acid gases. Based on decision tree analysis, we found two main design paths of the optimal PPNs for natural gas sweetening, which are the PPNs with LCD ≤ 4.648 Å, Vf ≤ 0.035, and PLD ≤ 3.889 Å, and those with 4.648 Å ≤ LCD ≤ 5.959 Å, ρ ≤ 837 kg m−3. In addition, we constructed different machine learning models, particularly artificial neural network, available to accurately predict the APS of PPNs. 2D projection map of geometrical properties of PPNs using the t‐distributed stochastic neighbor embedding (t‐SNE) method shows that the screened 390 samples exhibit the similar structures. Among the top‐23 PPNs with the highest APS, hPAFs‐0201 has enhanced natural gas sweetening performance due to its strong affinity between the N‐rich organic linkers and acid gases. hPAFs‐0752 shows the highest isosteric adsorption heat of H2S and CO2 (Q°st = 49.84 kJ mol−1), resulting in its second‐highest APS as well as high hydrophilicity. Based on the combination of molecular simulation and machine learning, comprehensive insights into the high‐throughput screening of PPNs in this work will provide new ideas for the design of high‐performance PPNs for gas separation. [ABSTRACT FROM AUTHOR]

CH4 is considered as an environmentally benign fuel and there is considerable interest in the development of new materials for CH4 storage. In this study, 424 tetrazolate-based metal–organic frameworks (MOFs) were computationally designed including 304 structures with the, urr and fcu topological nets and 120 structures with diverse nets. The CH4 deliverable volumetric capacities of all designed nanoporous materials and the adsorption isotherms of the top 10 hypothetical MOFs with high volumetric deliverable capacity at 298 K were predicted using molecular simulations. From the simulation results, tetrazolate blocks adjacent to pyrene or dibenzene linkers in fcu topological MOFs were found to provide lower density CH4 storage at delivery pressure (5.8 bar) as well as more efficient CH4 packing at charge pressure (65 or 35 bar), resulting in an obvious enhancement in CH4 deliverable volumetric capacity. The predicted CH4 deliverable capacity of Zr-fcu-MOF-2Py between 65 and 5.8 bar can reach 177 cm3 (STP) cm−3, the highest among tetrazolate-based MOFs studied. In comparison with NU-Py-fcu (with carboxylate blocks and pyrene linkers), its deliverable capacity increases 45.1% from 122 to 177 cm3 (STP) cm−3 under the same conditions. The enhancement mechanism from microscopic insights provided details on how the incorporation of tetrazolate links into MOFs would affect CH4 adsorption and delivery. This will lead to a novel way to enhance CH4 volumetric delivery capacity through finely tuning the chemical environment of MOFs with the incorporation of polar functional groups such as tetrazolate blocks. [ABSTRACT FROM AUTHOR]

Correction for 'High-throughput computational screening of hypothetical metal–organic frameworks with open copper sites for CO2/H2 separation' by Mengmeng Li et al., Phys. Chem. Chem. Phys., 2022, 24, 18764–18776, https://doi.org/10.1039/D2CP01139E. [ABSTRACT FROM AUTHOR]