earticle

영어

One-dimensional (1D) nanostructured materials in nanorod form have attracted many attentions due to their unique properties derived from low dimensionality and quantum confinement effect. Many nanorod shaped metal oxide materials have been synthesized using various procedures including a biomimetic method called biomineralization. Among various metal oxides, titanium oxide (TiO2) is stable and harmless to environment, finding its useful applications in many areas including photocatalysts, sensors, memory devices and solar cells. In the present study, we demonstrate the synthesis of nanorod shaped TiO2 using a bacteriophage as a template to guide 1D TiO2 nucleation and subsequent growth along the virus axis. To render this virus-mediated biomineralization of the nanorod shaped TiO2, a genetically engineered phage (f88-STB1) was constructed by genetically fusing TiO2 affinity peptide STB1 (CHKKPSKSC)[1] to a major viral coat protein (pVIII) of the wild-type virus f88. Following confirmation of STB1- fused pVIII expression on the f88-STB1 in approximately 150 copy numbers, it was shown that the f88-STB1 exhibited specific and electrostatic binding affinity to TiO2 at pH 9 where indigenous but nonspecific affinity of the wild-type virus to TiO2 was found abolished almost completely. Since affinity of biomolecules toward TiO2 is necessary for biomineralization, nanorod shaped TiO2 synthesis at pH 9 was enabled only when the reaction was catalyzed by the engineered phages. Furthermore, reaction conditions (e.g. pH, ionic strength, concentrations of viruses and precursors) were found to affect significantly the efficiency of the virus mediated TiO2 biomineralization. Finally, nanorod shaped TiO2 produced in this study was analyzed by SEM, TEM, EDS and XRD to compare its characteristics with the conventional TiO2 in particle form.