Facile Preparation of Biomass-Derived Mesoporous Carbons for Highly Efficient and Selective SO₂ Capture

The efficient elimination of SO2 from flue gases and natural gases is critical for energy utilization and environmental protection. However, selecting or preparing an efficient adsorbent with a high SO2 capacity, good selectivity, and excellent recyclability is very challenging, and the adsorption mechanism at an atomic level is still controversial. We report a facile one-step method for the synthesis of biomass-derived porous carbons with high specific surface areas (1195–1449 m2 g–1), mesoporous pore size (4–6 nm), and good SO2 adsorption properties. Our carbon adsorbents exhibited an outstanding SO2 adsorption capacity of 10.7 mmol g–1 at 298 K and 1.0 bar, which is more than twice the SO2 capacity of benchmark carbon material cs1000a (approximately 5.0 mmol g–1) and commercial ordered mesoporous carbon CKM-3 (5.1 mmol g–1). The new carbon adsorbents also showed unprecedented SO2/CO2, SO2/CH4, and SO2/N2 separation selectivities of 32, 127, and 2349, respectively, which are comparable with the best performance MOF adsorbents. Dynamic breakthrough experiments confirmed the feasibility of efficient removal of SO2 from flue gas in an adsorbent column. Even with the presence of water vapor, clear and efficient separation of SO2 could also be achieved with excellent recycling stability. In addition, a density function theory simulation further illustrates that −NOx and −OH groups in the carbon frameworks provide strong interactions with SO2 molecules. The carbon adsorbents synthesized in this work are promising for flue gas desulfurization and natural gas purification applications

Deciphering the resistance mechanism of RET kinase mutant against vandetanib and nintedanib using molecular dynamics simulations

The RET protein is a transmembrane receptor tyrosine kinase (RTK) whose oncogenic mutations or fusions are closely related to human cancers such as thyroid and non-small cell lung cancer. Vandetanib as a clinical-approved protein-tyrosine kinase inhibitor (TKI) exhibits anti-cancer efficacy by blocking the RET ATP-binding site, but drug resistance was observed for the RETG810A mutant. Recent studies have identified another TKI nintedanib as an effective molecule to inhibit vandetanib-resistant RETG810A. However, there is no clear evidence of why nintedanib and vandetanib displayed different inhibitory activities towards RETG810A. Here, we exploited molecular dynamic (MD) simulations to compare the interactions of the RETG810A mutant with nintedanib and vandetanib. A higher structural flexibility of the activation loop was observed in the nintedanib-bound RETG810A, which may result in discrepant autophosphorylation activity in the nintedanib- and vandetanib-bound RET kinase, causing differentiated pharmacological effects of the two compounds. Molecular mechanics/Poisson-Bolzmann surface area method suggested that nintedanib had a higher affinity towards RETG810A over vandetanib, accounting for its better inhibitory effect as an ATP-competitive compound. These results depicted the underlying mechanism for the different inhibitory efficacy of nintedanib and vandetanib on RETG810A from both conformational and energetic aspects. Furthermore, we also found that both compounds maintained the ‘DFG-in, αC-helix-in, and activation loop-open’ conformation of RETG810A, which is the characteristic of the active state. Together, our results provide comprehensive mechanistic insights into nintedanib’s capability in inhibiting vandetanib-resistant RET mutant and enlighten future structural-based optimisation of RET TKIs to overcome drug resistance.</p

Additional file 1 of Establishment of early diagnosis models for cervical precancerous lesions using large-scale cervical cancer screening datasets

Additional file 1. Other details of this study