磁性荧光双功能纳米粒子的制备及皮肤上指纹检测应用

【作者】 刘娜；

【导师】 吕家根；

【作者基本信息】 陕西师范大学 ， 分析化学， 2012， 硕士

【摘要】 指纹是人类(包括灵长类)特有的皮肤纹线形态,具体是指人体手部皮肤表面的乳突花纹,是典型的遗传性状。指纹作为一种物证被誉为“证据之首”已为举世所公认,广泛应用于查缉案件、认证罪犯。如何在犯罪现场种类繁多的客体上发现、显现和收集它,是指纹利用的关键问题。经过刑侦工作者一个多世纪的探索、研究和实践,大多数客体上遗留的指纹都能够成功显现。但现有的显现方法对于一些特殊的客体上遗留的指纹显现率并不高。如一些暴力案件常常需要从被害人身体上提取指纹,由于人体皮肤表面存有细毛和汗孔,容易干扰手印纹线,特别是皮肤上的汗腺和皮脂腺能不断分泌出汗液和皮脂液,容易混染皮肤上的指纹残留物质,再加上皮肤本身的伸缩性较大,因此皮肤上指纹的显现是国际上刑侦工作者面对的一大难题。本文结合磁性纳米材料和荧光纳米材料的优异性能制备了具有磁性荧光双功能的纳米材料,并将其运用于皮肤上指纹的显现。本文一共分为三章。第一章是综述,主要介绍了现有皮肤上指纹显现方法的优缺点,磁性纳米材料、荧光纳米材料及核壳结构双功能纳米材料的基本概念、性质及其应用。第二章和第三章为研究报告,研究报告部分内容简要介绍如下1.采用共沉淀法制备了磁性Fe3O4纳米粒子,为了防止后续制备的Fe3O4/SiO2@Gd2O3:Eu, Bi纳米粒子荧光强度太低,用二氧化硅对其表面进行修饰,并用透射电子显微镜以及红外吸收光谱对制备的Fe3O4纳米粒子及Fe3O4/SiO2复合纳米粒子进行了表征。2.采用共沉淀法以稀土硝酸盐为原料制备了Bi3+做敏化剂的Gd2O3:Eu, Bi纳米粒子；并在此基础上以Fe3O4/SiO2复合纳米粒子为磁性核,采用沉积法制备了核壳结构的Fe3O4/SiO2@Gd2O3:Eu, Bi纳米粒子,该粒子同时具有良好的磁性能和荧光性能；将制备的磁性荧光Fe3O4/SiO2@Gd2O3:Eu, Bi纳米粒子用于皮肤上指纹的显现,显现后皮肤上指纹轮廓清晰可见且呈现出一定的指纹纹路。更多还原

【Abstract】 Fingerprint is special skin ridge lines form of human (including primates) and typical of genetic traits, it refers to mastoid patterns of the human hand skin surface. Fingerprint as the first of the material vidence has been recognized by the world and widely used in investigation cases. Therefore, the main problem of usi ng fingerprint is finds it on a wide variety of objects at the scene of the crime. Fingerprints left on most subject can be discovered by forensic workers through exploration, research and practice more than a century. However, the existing methods have some limitations for some special object of the fingerprint left. As some violence case often need extracting fingerprint from the victim body. Because of the human skin surface has sweat gland and sebaceous gland. The fingerprint residues were easily contaminat by secretions on skin substance, coupled with the greater scaling of the skin itself. Therefore, the discovered of fingerprint on human skin surface is a major challenge for forensic workers. Magnetic fluorescent bifunetional nanomaterials were prepared using superior performance of magnetic and fluorescence nanomaterials. It was used to detect fingerprint on skin surface.Three chapters are included in this thesis. One chapter is review, mainly introduced the advantage and disadvantage of the existing methods for detecting fingerprint on the skin surface. The basic concepts, character and application of magnetic, fluorescence and magnetic bifunetional nanomaterials were introduced. The second chapter and the third chapter are research reports, and the main contents are as follows:1. Fe3O4magnetic nanoparticles were prepared by coprecipitation. In order to prevent the fluorescence intensity of Fe3O4/SiO2@Gd2O3:Eu, Bi nanoparticle is too low. We made a surface modification to Fe3O4/SiO2nanomaterials. The synthesized of Fe3O4and Fe3O4/SiO2nanomaterials were characterized by SEM and IR respectively.2. Rare earth nitrate for raw materials prepared Gd2O3:Eu, Bi nanoparticle by total precipitation method. Fe3O4/SiO2nanoparticle as a magnetic nuclear prepared Fe3O4/SiO2@Gd2O3:Eu, Bi nanoparticle of shell structure by total precipitation method. The particle has excellent magnetic properties and fluorescence property at the same time with. Application of Fe3O4/SiO2@Gd2O3:Eu, Bi powder for detecting latent fingerprint on skin surface. After detecting, the fingerprint profile is clearly visible and renders some fingerprint ridges.更多还原