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Graphitic carbon nitride (GCN) is a versatile photocatalytic material with applications in water treatment, hydrogen production, CO₂ reduction, and organic synthesis due to its 2D structure and semiconducting properties. Its experimental band gap of ∼2.7 eV makes it active under visible light, facilitating photocatalytic reactions such as pollutant degradation, water splitting, and CO₂ conversion. To enhance its utility, strategies to lower GCN's band gap through doping are being actively explored. Transition metal and non-metal doping have been investigated to improve GCN’s light absorption and electronic properties. Non-metal dopants, such as nitrogen, chalcogens, and halogens, offer high electronegativity and covalent bonding potential, leading to improved visible light activity. Despite these advances, detailed understanding of dopants’ atomic-level effects remains limited, making computational studies like density functional theory (DFT) essential. This study examines the effects of main-group element doping on corrugated heptazine-structured GCN. Group III dopants increase the band gap by introducing electron deficiencies, while Groups IV–VII dopants generally reduce the band gap due to larger atomic sizes and weaker electron binding. Unique behaviors, such as high band gaps from nitrogen and fluorine doping, are attributed to their strong electronegativity and small radii. The findings reveal periodic trends in dopant effects on GCN’s band structure, providing insights into rational dopant selection to optimize its electronic properties. These results highlight the potential of tailored doping strategies to enhance GCN’s performance in photocatalysis, energy conversion, and electronic applications.

Abstract Diesel oil contamination is a threat to environment and human health. Many technologies have been developed to address this issue; however, they are costly to be deployed in real-world oil remediation. Adsorption remains to be one of the most economical methods to remove oil from water. Here, we used banana peel biochar (BPBC) immobilized in teabags as an adsorbent for the removal of diesel oil in water. We investigated the adsorption behavior of BPBC under different conditions, examining the influence of adsorbent loading, pH, salinity, and contact time on its efficiency for removing diesel oil in water. Our results show that the sorption capacity of BPBC is significantly affected by the amount of adsorbent used. Lower biochar loadings enhance the sorption capacity due to greater surface area accessibility, while higher loadings lead to decreased efficiency due to pore blockage and reduced surface exposure. Interestingly, the pH of the solution was found to have minimal impact on the sorption process. This is attributed to diesel oil’s hydrophobic and non-polar nature, which leads to its interaction with BPBC being predominantly governed by hydrophobic forces instead of pH-sensitive electrostatic interactions. Salinity emerged as a crucial factor in the adsorption process. An increase in salinity enhances the sorption capacity, likely due to the “salting-out” effect, where higher salt concentrations decrease the solubility of diesel oil, promoting its adsorption onto the biochar surface. Furthermore, the study highlights the importance of contact time, with longer exposure resulting in increased sorption capacity. This trend is explained by the adsorption kinetics, initially characterized by rapid adsorption, followed by a slower, progressive occupation of the biochar’s adsorption sites. The kinetic analysis of the process suggests that the pseudo-second-order model is more suitable, indicating a chemisorption mechanism. The Harkins–Jura isotherm model was identified as the best fit for explaining the isotherm behavior, owing to its capacity to account for the heterogeneous nature of the biochar surface and the formation of multiple adsorbate layers. The optimum conditions for maximum diesel oil removal are as follows: BPBC loading of 0.50 g, a solution pH of 5.00, a salinity concentration of 12,656.57 mg/L, and a contact time of 240 min. Under these conditions, BPBC exhibited an adsorption capacity of 19.04 g/g. In summary, our research establishes BPBC, particularly when contained within teabags, as an efficient and practical adsorbent for diesel oil removal in water. Its effectiveness, superior to other biochar, is mainly due to its porosity and hydrophobic properties. These findings not only enhance our understanding of BPBC’s adsorption capabilities but also underscore its potential for environmental remediation. Graphical Abstract

Abstract Enhanced oil recovery (EOR) relies on the use of surfactant to flood the wellbore and thus extract the oil from the rocks. However, current surfactants used for EOR are non-biodegradable and are made from toxic chemicals. Here, we report the potential of soybean lecithin as a biobased surfactant for enhancing oil recovery by stabilizing oil-in-water (O/W) emulsions. Our findings show that pH has a significant impact on stability, with lower pH levels leading to improved stability. Salinity affects stability, but soybean lecithin shows minimal sensitivity to salt concentration. Surfactant loading also plays a crucial role, with higher concentrations causing instability. The optimized operating parameters for soybean lecithin are determined to be at pH = 4, salinity = 84,171.08 ppm, and surfactant loading = 4.48 wt.%. Comparative evaluation reveals that soybean lecithin performs competitively, outperforming certain commercial surfactants in terms of emulsion stability in oil phase. The solubilization ratio of oil (SRo) values are lecithin = 3.2219, CAPB = 0.7028, CTAC = 11.1044, NP10EO = 11.1570, and SLES = 11.7067. Utilizing soybean lecithin as a biobased surfactant in enhanced oil recovery offers a sustainable and environmentally friendly alternative with potential economic advantages. Further research can focus on optimizing formulation and exploring synergies with other additives.

The rational selection of dopants for graphitic carbon nitride (GCN) is essential for tailoring its electronic properties, enabling advancements in photocatalysis, energy conversion, and electronics. Modifying the band gap, valence band edge (VBE), and conduction band edge (CBE) of GCN can enhance its light absorption capabilities, with narrower gaps improving visible light absorption and wider gaps increasing stability while lowering electron-hole recombination rates. Transition metals serve as effective dopants due to their distinct electronic configurations, allowing precise tuning of GCN's electronic structure. Early transition metals like titanium and vanadium reduce the band gap, enhancing conductivity for catalytic applications. Mid-transition metals such as iron and cobalt maintain structural integrity while optimizing electron mobility, ideal for stable catalytic systems. Late transition metals, including palladium and silver, provide highly conductive pathways with significant band gap reduction, suitable for high-performance catalysis and electronics. Strategic dopant selection, considering both functionality and sustainability, is vital for achieving high-performing, economically viable materials. Overall, the findings pave the way for tailored materials that address challenges in energy storage and environmental sustainability, highlighting the potential of doped GCN as a versatile candidate for innovative electronic and catalytic systems.

Using environmentally friendly solvents for liquid–liquid extraction offers a promising avenue for promoting sustainability in various industries. Green solvents, including ionic liquids, deep eutectic solvents, supercritical fluids, and bio-based solvents, offer several advantages compared to the traditional solvents of the present time. These solvents possess low toxicity, biodegradability, and reduced environmental impact, making them highly desirable for liquid–liquid extraction processes. Through careful adjustments in composition and physicochemical properties, these solvents can be customized to achieve efficient and selective extraction of desired compounds. Additionally, recent advances in green solvents often contribute to improved energy efficiency, reduced waste production, and the potential for developing novel products with unique characteristics. By embracing green solvents for liquid–liquid extraction, industries can actively contribute to sustainable development, minimize environmental harm, and support the transition towards an eco-friendlier future.

In recent years, metal–organic frameworks (MOFs) have gained a lot of attention from researchers because of their potential applications in gas separation, storage, catalysis, as well as sensing. In spite of this, further development for the actual utilization of this material is hindered mainly by its lack of ability to withstand harsh conditions. Advances over the past few years have made it possible to create MOFs with greater variability and structural properties that are more robust in nature. This paper focuses on the development of synthesis and design of MOFs so as to attain robust frameworks that are relevant for various applications. Finally, this paper also discusses the possible future directions of study for synthesizing highly durable MOFs.

Pneumatic conveying is a vital technology for delivering bulk solids, powders, and granular materials in various industries. Significant advances in pneumatic conveying technology have occurred in recent years, spurred by the demand for sustainable and energy-efficient industrial processes. This paper explores the current advances in pneumatic conveying technology and their implications for the industry. First, the principles of pneumatic conveying are discussed. Then, two significant advances in pneumatic conveying technology are highlighted. Schenck Process, for example, has created the Enhanced Dilute Phase Pneumatic Conveying (EDIP) system, the E-Finity continuous dense phase system, and high-pressure systems utilizing Lontra’s LP2 Compressor Blower. Second, Palamatic Process provides dense-phase vacuum conveying cyclones as well as powder pumps for nonabrasive dense-phase vacuum conveying. Several research gaps in pneumatic conveying technology are identified in the paper, including the integration of artificial intelligence and machine learning, the optimization of multiphase flow behavior, energy efficiency and sustainability, material degradation, and particle damage, handling of cohesive and difficult-to-convey materials, scale-up and design optimization, and real-time monitoring and control systems. The future outlook highlights the potential of sustainable practices to advance pneumatic conveying technology further. The integration of these technologies can lead to improved performance, energy efficiency, and sustainability in pneumatic conveying systems.

Recent advancements in particle dispersion modeling have significantly enhanced our understanding and capabilities in predicting and analyzing the behavior of particulate matter in various environments. However, this field still confronts several research gaps and challenges that span across scientific inquiry and technological applications. This paper reviews the current state of particle dispersion modeling, focusing on various models such as Lagrangian, Eulerian, Gaussian, and Box models, each with unique strengths and limitations. It highlights the importance of accurately simulating multi-phase interactions, addressing computational intensity for practical applications, and considering environmental and public health implications. Furthermore, the integration of emerging technologies like machine learning (ML) and artificial intelligence (AI) presents promising avenues for future advancements. These technologies could potentially enhance model accuracy, reduce computational demands, and enable handling complex, multi-variable scenarios. The paper also emphasizes the need for real-time monitoring and predictive capabilities in particle dispersion models, which are crucial for environmental monitoring, industrial safety, and public health preparedness.

Heavy metal contamination in groundwater has become more prevalent due to the leaching of toxic wastes from various anthropogenic sources. When ingested, this can cause serious ill effects detrimental to human health. Hence, there is a need to monitor the levels of heavy metals in various water sources to ensure that they are fit for human consumption. Standard detection methods such as AAS and ICP-MS are typically used for quantifying the concentration of heavy metals. However, these require expensive equipment, not to mention the need for a trained and highly-skilled technician to operate the equipment. Nanosensors offer a low-cost alternative to these methods. By utilizing the localized surface plasmon resonance (LSPR) and the properties of noble metal nanoparticles such as AgNPs, the colorimetric detection of heavy metals is made possible. Herein, we report the synthesis of humic-acid-functionalized silver nanoparticles (HA-AgNPs) using a borohydride reduction approach as a colorimetric nanosensor for Ni (II) detection in aqueous solutions. Humic acid acts as a capping agent that stabilizes the AgNPs in the colloidal mixture while providing functional groups for the detection of heavy metals. The synthesized HA-AgNPs had an average hydrodynamic diameter of 42.9 nm, a polydispersity index of 0.438, and an LSPR peak of 400.6 nm. The nanosensor could be used for the colorimetric detection of Ni (II) ions within the linear range of 0.15–0.40 mM Ni (II) with a limit of detection (LoD) of 2.35 mg L−1. The HA-AgNPs were shown to be selective when detecting Ni (II) ions; common metals in water such as Ca (II), Mg (II), Al (III), Zn (II), Na (I), and K (I) did not interfere with Ni (II) detection. As such, HA-AgNPs can be used as reliable and environmentally friendly colorimetric nanosensors for the rapid and point-of-need detection of Ni (II) ions in aqueous solutions.

Distillation is widely recognized as the preferred method for separation due to its operational and control benefits. Traditional distillation processes, however, cannot successfully separate azeotropic mixtures with near boiling points. Numerous special distillation processes have been developed to address this limitation. Extractive distillation, in particular, has gained significant popularity in the chemical, petrochemical, pharmaceutical, and refining industries. This review examined the state-of-the-art advances in extractive distillation. The importance of the proper selection of a solvent was discussed. Several configurations of extractive distillation processes were presented. Additionally, alternative extractive distillation systems have been elaborated. However, significant research gaps remain, such as the need for an exhaustive investigation of various control variables, the impact of certain entrainers on distillation processes, and cost comparisons across specialized distillation systems. Furthermore, process intensification strategies require additional research to solve complexity and operability issues. The integration of energy-efficient technologies, developments in renewable energy consumption, and the development of cost-effective reactive or split distillation columns will shape the future of distillation operations. These advances will help the chemical process sector achieve improved energy efficiency, lower environmental impact, and increased sustainability.

Recent advances in nucleation and crystal growth have revolutionized our understanding and control of crystallization processes. This paper highlights key developments in this field and the processes and technologies involved in its continuous growth. Advanced computational models have allowed for precise prediction of nucleation rates and crystal morphologies, facilitating the rational design of materials with desired properties. Innovative strategies have also emerged, enabling enhanced control over crystal growth kinetics and crystallographic orientations. Process intensification strategies, including microreactors and membrane crystallization, enhance nucleation rates and crystal growth. Advances in the potential-driven growth of metal crystals from ionic liquids, including protic ionic liquids (PILs) and solvate ionic liquids (SILs), are discussed. Lastly, current research gaps and future prospects in the field of nucleation and crystal formation are highlighted. The integration of cutting-edge experimental techniques, computational modeling, and novel strategies will drive the understanding of nucleation and crystal growth processes, allowing for the development of materials with tailored properties and enhanced functionality across multiple disciplines.

Plastic waste has increased worldwide due to the steady rise in plastic consumption. Several strategies were developed to mitigate plastic waste. Among these methods, pyrolysis is a promising technology for converting plastic waste into valuable products. This paper discusses the latest advancements in the pyrolysis of three common types of plastic waste: polyvinyl chloride (PVC), polypropylene (PP), and polystyrene (PS). The challenges associated with the pyrolysis of these plastics are highlighted, and an outlook on the future of research on pyrolysis is given. Overall, this review provides valuable insights into the current state of research on the pyrolysis of PVC, PP, and PS. This has implications for advancing pyrolysis technology to contribute to a more sustainable and circular economy.

Recent advances in particle fluidization focus on improving the efficiency and control of various processes used in different industries. New technologies, such as spouted beds and circulating fluidized beds, have emerged to improve particle distribution. Additionally, the integration of computational fluid dynamics (CFD) simulations and other advanced technology leads to the effective observation of particle fluidization behavior and up-scaling of fluidized beds. In this paper, we aim to give a thorough analysis of studies from various research groups in the field of particle fluidization. The fundamentals of fluidization, recent advanced techniques, models and simulations, and application of the process will be emphasized. Moreover, it discusses various aspects regarding the challenges and opportunities of the fluidization process. Advances in particle fluidization hold great promise for improving industrial processes and enabling technologies in various industries.

Carbon dioxide (CO2) capture and separation constitute an important field of research as we seek to reduce the effects of climate change. Because of their porosity, resilient crystallinity, high adsorption capacity, and affinity for CO2, cyclodextrin-based metal-organic frameworks (CD-MOFs) have emerged as attractive materials for carbon capture. This paper gives an overview of CD-MOFs and their applications in CO2 capture and separation. Several studies have been conducted to synthesize and characterize CD-MOFs for CO2 capture. The causes of the high binding affinity of CO2 in CD-MOFs were discovered through mechanistic studies on CO2 adsorption. Furthermore, CD-MOF modifications have been carried out to improve the sorption capacity and selectivity of CO2 adsorption. Meanwhile, several researchers have reported using CD-MOFs for gaseous CO2 membrane separation. This paper also highlights the current gaps in CD-MOF research and future outlooks in carbon capture and separation using CD-MOFs.

Metal–organic frameworks (MOFs) are a class of material made up of metal ions or clusters and organic linkers. Cyclodextrin-based MOFs (CD-MOFs) are gaining popularity among MOFs due to their unique features, such as high porosity, permanent porosity, and biocompatibility. This paper focuses on recent advances in synthesizing CD-MOFs and their water stability. We highlight the difficulties involved in CD-MOF synthesis and the strategies explored to increase water stability. The advances in CD-MOF synthesis and characterization open new avenues for tailoring crystal growth processes and properties, with potential applications spanning areas such as catalysis, drug delivery, and environmental remediation. The combination of innovative synthesis techniques, systematic parameter exploration, and functionalization strategies heralds a promising era for crystal growth research and applications. Finally, we discuss the current research gaps and the future outlook of CD-MOF research. Overcoming obstacles in the synthesis and water stability of CD-MOFs is crucial for their practical applications.

Particle characterization is critical in industries that are influenced by particle size distribution. Understanding particle behavior is crucial for product quality control and manufacturing process optimization. Particle characteristics significantly affect material performance and properties. This review paper examines the importance of particle characterization in many industries and focuses on particle size and shape measurement. This paper begins by delving into particle size and size distribution analysis, emphasizing the impact of particle size on material properties and the many methodologies used for particle size analysis. This paper then examines particle shape characterization and its impact on material characteristics. It gives an overview of particle characterization techniques and the criteria for selecting the best technique for a given sample. Particle characterization in ceramics, food, cosmetics, medicines, and metallurgy are also thoroughly discussed. Overall, this work emphasizes the importance of particle characterization in numerous industries and provides insights into particle size and shape measurement.

Reactive distillation (RD) combines chemical reactions and separation in a single unit essential to equilibrium-limited reactions. This new technique encompasses multiple advantages over traditional processes, including lower operating costs, increased thermal energy efficiency, high product selectivity, high purity percentage, and lower environmental impact. This paper provided an overview of the features, industrial applications, and industrial perspective of advanced reactive distillation technologies (ARDTs). This study focused on five under-development ARDTs: reactive dividing wall column (R-DWC), reactive high-gravity distillation (R-HiGee), reactive heat-integrated distillation column (R-HIDiC), catalytic cyclic distillation (CCD), and membrane-assisted reactive distillation (MA-RD). The primary drivers for new RD applications are reduced number of vessels, reduced residence time and holdup volume, increased mass and heat transfer, overcoming azeotropes, and prefractionation or impurity removal. ARDT’s potential has yet to be studied, and research remains active to improve it further by investigating other RD technologies, simulation, and optimization techniques.

SARS-CoV-2 caused the ongoing COVID-19 pandemic, and only a few treatment options are available to mitigate its impact on human health. Hence, there is a need to discover drugs that could be used to treat COVID-19. Several studies have already reported the repurposing of existing drugs to inhibit the receptor-binding domain of SARS-CoV-2. However, the emergence of COVID-19 variants may render current drug candidates ineffective. Here, we report the structure-based drug screening of the DrugBank database against the wild-type, B.1.1.7, B.1.351, and P.1 variants of SARS-CoV-2. Our study revealed that Salmeterol, Abediterol, and Lysophosphatidylglycerol are among the top candidates against all four variants. Furthermore, we showed that Salmeterol forms a stable complex with the receptor binding domain of SARS-CoV-2 variants. Further studies are needed to evaluate the clinical relevance of the drug candidates discovered. Nevertheless, this study provides insight into computational drug design that works against multiple variants of SARS-CoV-2.

Metal-organic frameworks (MOFs) are an evolving class of crystalline porous materials made of organic linkers and metallic nodes. The rich chemistry of MOFs allows them to have an almost infinite number of possible structures. Consequently, they have been of great interest because of their highly tunable properties and unique features, such as their high porosity, high surface area, structural stability, structural diversity, and tailorability. These enable MOFs to be a flexible catalytic platform for photocatalytic applications. Thus, this paper discusses the opportunities of MOFs for use in catalysis. In particular, the use of metal-organic frameworks as a photocatalyst is briefly discussed. Specifically, MOFs can be used as a photocatalyst for carbon dioxide reduction (CO2RR), nitrogen reduction reactions (NRRs), and water-splitting reactions (HERs and ORRs). However, using MOFs as catalytic platforms has some challenges that must be addressed to achieve commercialization. Therefore, this paper also discusses some prospects of designing MOFs for their specific catalytic applications to improve their catalytic properties and enhance selectivity. More importantly, an outlook is also provided on how MOF catalysts can further be developed to enable other catalytic reactions. Overall, MOFs have great potential as a photocatalytic material, provided they are uniquely designed to suit their intended applications.

Farmers widely use malathion, even in households, and significant amounts seep through groundwater and effluent wastewater. It is toxic to animal and human life. Hence, its removal from wastewater is necessary. Here, we report the applicability of hydroxyapatite as a catalyst in the UV-light-assisted degradation of malathion. The hydroxyapatite was synthesized via calcination from milkfish (MF1000) and cream dory (CD1000) bones. FTIR and PXRD results proved the successful synthesis of hydroxyapatite from the fish bones. SEM images revealed that the synthesized hydroxyapatite varies in size from 19 to 52 nm with a pseudo-spherical morphology. Degradation efficiency increases when catalyst dosage or irradiation time are increased. Degradation efficiencies range from 8.18% to 67.80% using MF1000 and from 20.50% to 67.90% using CD1000. Malathion obeys first-order kinetics with a kinetic constant up to 7.0289 × 10−3 min−1 for 0.6 g catalyst loading. Meanwhile, malathion obeys second-order kinetics with a kinetic constant up to 1.1946 × 10−3 L min−1 mg−1 for 0.6 g loading. Across all catalyst loadings, CD1000 has faster degradation kinetics compared to MF1000. The results of this study validate that the calcined fish bones are effective in removing malathion in an aqueous solution, which significantly lessens the detrimental effects of pesticides in groundwater and wastewater.

This paper investigates the general trends in the structural, electronic, and optical properties of anatase TiO2 photocatalysts co-doped with transition metals and sulfur. We attempt to rationalize co-dopant selection by employing molecular dynamics and density functional theory calculations. The structural properties of the first-row transition metal co-dopants were determined. TM-TiO2 and TM/S-TiO2 were structurally stable, with minimal changes in their lattice parameters, cell volume, density, and XRD profiles relative to pristine TiO2. However, only Fe and Mn among the first-row transition metals are thermodynamically favorable, i.e., their substitutional energies are lower relative to pristine TiO2. Intermediate energy levels (IELs) are formed during the co-doping of transition metals and sulfur on TiO2. In particular, Fe and Co form two IELs between the VBM and CBM, resulting in improved optical properties, especially in the visible-light region, which are mainly attributed to the unsaturated nonbonding transition metal d orbitals and the half-filled Ti–O bonding orbitals. On the other hand, Cu and Ni form three IELs close to each other due to the M–O anti-bond orbitals, half-filled p orbitals of S, and the Ti–S anti-bonding orbitals. These IELs in co-doped systems can serve as “stepping stones” for photogenerated electrons, facilitating easier charge mobility. Among the investigated co-doped systems, Fe/S-TiO2 was shown to be the most promising for photocatalytic applications.

Titanium dioxide has long been investigated for its excellent photocatalytic activity under UV illumination. However, its sluggish activity under visible-light illumination remains a challenge. Doping titanium dioxide with transition metals and non-metals was done in the past to improve its catalytic properties, yet the expensive synthesis protocols involved in doping titanium dioxide limit its applications. Herein, a one-pot approach to doping titanium dioxide nanotubes was used. In particular, the Cu/S-TiNTs electrode was synthesized by electrochemical anodization using an electrolyte solution spiked with CuSO4. The resulting nanostructured Cu/S-TiNTs electrode was used as a photoanode for the photoelectrocatalytic degradation of synthetic dye solution (50 ppm C.I. Basic Blue 9 in deionized water) in a 125-mL reactor. The Cu/S-TiNTs were shown to be catalytically active under both ultraviolet and visible light. Co-doping pristine TiNTs with copper and sulfur significantly enhanced the photoelectrocatalytic degradation rates of BB 9. Cu/S-TiNTs achieved a 67% faster degradation rate (k1 = 1.5054 ± 0.0193 × 10−2 min−1) compared to pristine TiNTs (k1 = 8.9106 ± 0.0647 × 10−3 min−1) under visible light illumination. At the end of 60 min, the Cu/S-TiNTs were able to degrade 59.69% of the initial dye concentration under visible light, compared to 45.43% degradation using pristine TiNTs. The synthesized photoanodes demonstrated good reusability and stability after several cycles of use, even at a low dopant loading. These findings bring us closer to the possibility of large-scale adaptation of advanced oxidation processes, such as photoelectrocatalysis, for environmental remediation of recalcitrant organic compounds in wastewater.

Most plastics on the market are based on petroleum. Because of their chemical inertness and durability, plastics are essentially non-biodegradable. Previously, plastic waste management typically focused on reusing and recycling it into valuable products. However, virgin plastic resins and their chemical processing to produce new plastic products are more economical than recycling. As such, most plastic waste ends up in dumpsites and sanitary landfills. Waste-to-energy conversion is a viable solution to the alarming rise of plastic proliferation in the Anthropocene age. The conversion of plastic wastes into valuable products such as liquid oils, fuel gas, and solid chars through a high-temperature pyrolytic process could lead to a source of alternative fuels. In this paper, the application of the pyrolysis process to polyethylene is discussed. Several process parameters were seen to influence the characteristics of the final pyrolysis products, such as the operating temperature, type of catalyst, and presence of agitation. Optimizing these key parameters is essential for the industrial adoption of the pyrolysis of plastics.

In this study, novel potential inhibitors of SARS-CoV-2 variants were designed de novo using generative neural networks. The top-performing ligand based on docking performance and ADMET profiles was CID #526. It forms several hydrogen bonds with wild-type SARS-CoV-2, indicating its potential as an inhibitor of the receptor-binding domain. Mutated variants of the RBD also showed good interactions with CID #526, implying the inhibitory properties of our top-performing compound against various variants. Molecular dynamics analysis showed a stable ligand–RBD complex. CID #526 can easily be synthesized using low-cost starting molecules. Overall, the generated ligands merit further investigation to determine their efficacy and safety as a treatment for COVID-19.

Here, potential inhibitors of the SARS-CoV-2 papain-like protease (PLpro) are reported. A drug molecule (PLpro-50), designed de novo using generative neural networks, interacts with PLpro via hydrogen bonding, forming a salt bridge, and π–π stacking, making it a promising drug against PLpro. PLpro-50 has an excellent ADMET profile with good absorbability, high clearance, and low toxicity. Molecular dynamics analysis revealed the stability of the receptor–ligand complex of PLpro-50 and PLpro. An organic retrosynthesis study showed the feasibility of PLpro-50 to be synthesized using low-cost starting materials. Further studies should be performed to determine whether the determined drug candidates are efficacious in treating COVID-19 infections.