Departamento de Ingeniería Química y Metalurgia, Universidad de Sonora, Rosales y Luis Encinas S/N, Hermosillo, Sonora, Mexico.
Nanotechnology. 2011 Sep 2;22(35):355601. doi: 10.1088/0957-4484/22/35/355601. Epub 2011 Aug 5.
Healthy epithelial cells, in vivo, have the ability to synthesize gold nanoparticles when aqueous tetrachloroauric acid is made to react with human skin. Neither a reducing agent nor a protecting chemical is needed for this bio-synthesis method. The first indication of gold nanoparticle formation is the staining of the skin, which turns deep purple. Stereoscopic optical micrographs of human skin tissue in contact with aqueous tetrachloroauric acid clearly show the staining of the epithelial cells. The UV-Vis spectrum of these epithelial cells shows an absorption band with a maximum at 553 nm. This absorption peak is within the wavelength region where the surface plasmon resonance (SPR) band of aqueous colloidal gold exhibits a maximum. Transmission electron micrographs show that gold nanoparticles synthesized by epithelial cells have sizes between 1 and 100 nm. The electron diffraction pattern of these nanoparticles reveals a crystalline structure whose interplanar distances correspond to fcc metallic gold. Transmission electron micrographs of ultra-thin (70 nm thick) slices of epithelial cells clearly and undoubtedly demonstrate that gold nanoparticles are inside the cell. According to high resolution transmission electron micrographs of intracellular single gold nanoparticles, they have the shape of a polyhedron.
健康的上皮细胞在体内具有合成金纳米粒子的能力，当水合四氯金酸与人体皮肤反应时。这种生物合成方法既不需要还原剂也不需要保护化学物质。金纳米粒子形成的第一个迹象是皮肤染色，它变成深紫色。与人接触水合四氯金酸的人体组织的立体光学显微镜照片清楚地显示了上皮细胞的染色。这些上皮细胞的紫外-可见光谱显示出一个在 553nm 处具有最大吸收带的吸收峰。这个吸收峰在水胶体金的表面等离子体共振 (SPR) 带表现出最大的波长区域内。透射电子显微镜照片显示，上皮细胞合成的金纳米粒子的尺寸在 1 到 100nm 之间。这些纳米粒子的电子衍射图案显示出与其对应的面心立方金属金的晶面间距的晶体结构。上皮细胞的超薄（70nm 厚）切片的透射电子显微镜照片清楚而无疑地证明了金纳米粒子在细胞内。根据细胞内单个金纳米粒子的高分辨率透射电子显微镜图像，它们具有多面体的形状。
