Silver powders were prepared by a chemical reduction method. Effects of different surfactants during this preparation process were examined. Using these silver powders, silver pastes were prepared for low temperature co-fired ceramics (LTCC) applications. Another batch of different surfactants were added into the silver paste and evaluated. Moreover, various organic thixotropic agents were used to modify the thixotropy behavior of the silver paste. It was found that the surfactants of PVP (Polyvinyl pyrrolidone, for preparation of the silver powder) and Span-85 (for the preparation of silver paste) exhibited the best performance, with an electrical resistivity of 0.11 mΩ mm. The silver paste with the thixotropic agent of hydrogenated castor oil shows the largest thixotropic index of 1.56. Using different organic additives, the microstructural, rheological and electrical properties of the silver paste can be considerably improved, and our results shed light on the optimization of the silver paste for LTCC applications.
Congcong Li,Chaoxi Chen,Yucai Wei,Min Tan,Shuo Zhai,Juebo Zhao,Lu Wang,Tao Dai
It is urgently needed to develop novel adjuvants for improving the safety and efficacy of vaccines. Metal-organic frameworks (MOFs), with high surface area, play an important role in drug delivery. With perfect biocompatibility and green preparation process, the γ-cyclodextrin metal-organic framework (γ-CD-MOF) fabricated with cyclodextrin and potassium suitable for antigen delivery. In this study, we modified γ-CD-MOF with span-85 to fabricate the SP-γ-CD-MOF as animal vaccine adjuvants. The ovalbumin (OVA) as the model antigen was encapsulated into particles to investigate the immune response. SP-γ-CD-MOF displayed excellent biocompatibility in vitro and in vivo. After immunization, SP-γ-CD-MOF loaded with OVA could induce high antigen-specific IgG titers and cytokine secretion. Meanwhile, SP-γ-CD-MOF also significantly improved the proliferation of spleen cells and activated and matured the bone marrow dendritic cells (BMDCs). The study showed the potential of SP-γ-CD-MOF in vaccine adjuvants and provided a novel idea for the development of vaccine adjuvants.
危险品化学品经营许可证（带存储）