Restoring large-scale bone defects, where osteogenesis is slow while infections lurk, with biomaterials represents a formidable challenge in orthopedic clinics. Here, we propose a scaffold-based multipurpose anti-infection and bone repairing strategy to meet such restorative needs. To do this, personalized multifunctional titanium meshes were produced through an advanced additive manufacturing process and dual "TiO-poly(dopamine)/Ag (nano)" post modifications, yielding macroporous constructs with micro-/nanoporous walls and nanosilver bullets immobilized/embedded therein. Ultrahigh loading capacity and durable release of Ag were accomplished. The scaffolds were active against planktonic/adherent bacteria (Gram-negative and positive) for up to 12 weeks. Additionally, they not only defended themselves from biofilm colonization but also helped destroy existing biofilms, especially in combination with antibiotics. Further, the osteoblasts/bacteria coculture study displayed that the engineered surfaces aided MG-63 cells to combat bacterial invasion. Meanwhile, the scaffolds elicited generally acceptable biocompatibility (cell adhesion, proliferation, and viability) and hastened osteoblast differentiation and maturation (alkaline phosphatase production, matrix secretion, and calcification), by synergy of micro-/nanoscale topological cues and bioactive catecholamine chemistry. Although done ex vivo, these studies reveal that our three-in-one strategy (infection prophylaxis, infection fighting, and bone repair) has great potential to simultaneously prevent/combat infections and bridge defected bone. This work provides new thoughts to the use of enabling technologies to design biomaterials that resolve unmet clinical needs.

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Binary Cu−Cr−O and Cu−Ce−O oxides were studied in this work as regenerable sorbents for high-temperature fuel gas desulfurization. CuO−Cr2O3 and CuO−CeO2 sorbents can remove H2S from simulated coal-derived fuel gas to less than 5−10 ppmv in the temperature range of 650−850 °C. The presence of stable CuCr2O4 in CuO−Cr2O3 solids retains some copper in the Cu2+ or Cu1+ oxidation state, which can account for the high H2S removal efficiency. In CuO−CeO2 sorbents, however, CuO is easily reduced to copper metal. Participation of reduced cerium oxide in sulfidation can explain the observed high desulfurization efficiency. TGA tests and XRD analysis indicate that sulfidation proceeds through partial initial reduction of the CuO−Cr2O3 sorbents:  CuO → Cu/Cu2O → Cu x S (x < 2). Reduction kinetics were studied in the TGA over temperature ranges of 550−850 and 350−850 °C, respectively, for the CuO−Cr2O3 and CuO−CeO2 materials. The sulfidation kinetic parameters were measured in the temperature range of 450−850 °C after prereduction of both sorbents. The sulfidation of metal copper in Cr2O3 and CeO2-x matrices is a fast reaction with low activation energy, 19.8 and 16.6 kJ/mol, respectively. Both types of sorbents can be fully regenerated with diluted air. The regeneration temperature affects the reaction pathway and the regenerability of the solid composition.

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