Adigun Oluwamayowa O, Novikova Gloria, Retzlaff-Roberts Erin Lynn, Kim BongSuk, Miller Jeffrey T, Loesch-Fries L Sue, Harris Michael T
480 Stadium Mall Drive, School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, United States.
915 West State Street, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, United States.
J Colloid Interface Sci. 2016 Dec 1;483:165-176. doi: 10.1016/j.jcis.2016.07.028. Epub 2016 Jul 15.
There is a lack of fundamental information about the molecular processes governing biomineralization of inorganic materials to produce nanostructures on biological templates. This information is essential for the directed synthesis of high quality nanomaterials via biotemplating. We characterized palladium (Pd) mineralization via the individual adsorption, reduction, and nanocrystal growth processes, which simultaneously occur during the hydrothermal synthesis on the Tobacco mosaic virus (TMV). The adsorption of precursor and reduction of palladium were decoupled through UV-vis Spectroscopy and in situ X-ray absorption spectroscopy studies. The role of additional cysteine (Cys) residues, ionic strength, and coating density on the fundamental parameters describing these processes were quantitatively evaluated. Primary nanocrystal growth and structural orientation of Pd nanoparticles was characterized using in situ small angle X-ray scattering. The adsorption, reduction of Pd species, and nanocrystal sizes were significantly changed on addition of Cys residues to the amino terminus of the TMV coat protein. Reduction of Pd on an already coated virion was dependent on the Pd surface area, and was hindered by the presence of residual salt. Furthermore, trends in Pd adsorption intensity and capacity suggested that chloride ions affected the adsorption equilibrium. Application of this fundamental approach with further optimization of parameters dictating biomineralization would facilitate directed synthesis and scale up of bioinorganic systems.
关于控制无机材料生物矿化以在生物模板上生成纳米结构的分子过程，目前缺乏基础信息。这些信息对于通过生物模板法定向合成高质量纳米材料至关重要。我们通过在烟草花叶病毒（TMV）上进行水热合成过程中同时发生的单个吸附、还原和纳米晶体生长过程，对钯（Pd）矿化进行了表征。通过紫外可见光谱和原位X射线吸收光谱研究，将前驱体的吸附和钯的还原解耦。定量评估了额外的半胱氨酸（Cys）残基、离子强度和涂层密度对描述这些过程的基本参数的作用。使用原位小角X射线散射对Pd纳米颗粒的初级纳米晶体生长和结构取向进行了表征。在TMV衣壳蛋白的氨基末端添加Cys残基后，Pd物种的吸附、还原以及纳米晶体尺寸发生了显著变化。已包被病毒体上的Pd还原取决于Pd的表面积，并且受到残留盐的阻碍。此外，Pd吸附强度和容量的趋势表明，氯离子影响吸附平衡。应用这种基本方法并进一步优化决定生物矿化的参数，将有助于生物无机系统的定向合成和扩大规模。
