Selective Recognition by Nanoparticle Imprinted Thin Films

由于制备具有非常有趣的功能特性的纳米颗粒的能力大大超过了预测这些材料的毒理学危害的能力，因此评估人造配体壳保护纳米颗粒（NPs）的存在、分布和毒理学潜力成为一个日益紧迫的问题。人们普遍认为，纳米材料的毒理学危害不仅来自其元素组成，而且在很大程度上来自其尺寸、形状和配体壳的化学性质。因此，毒性测试涉及昂贵且种类繁多的测定，包括在NP可用于技术应用之前所需的动物测试。目前还没有一种简单有效的方法来检测环境中特定纳米粒子的存在。本项目旨在提供一种新的、简单有效的方法来选择性地检测纳米粒子，并利用纳米粒子印迹矩阵（NAIM）来预测它们与生物材料的相互作用。该概念最近首次由申请人证明用于NP的尺寸区分。在模板NP的存在下形成基质。在释放NP之后，印迹腔能够选择性地再摄取分析物NP。在该项目中，该方法将被显著扩展，以探索对不同外壳的选择性。我们的工作已经证明，NAIM应该由薄膜制成，因为这允许通过基板电极寻址截留的NP。将使用不同的化学物质来获得NAIM，以提供表面基团的大的可变性来检测不同的配体壳系统。这些方法包括通过还原预固定的NP周围的官能化芳基重氮离子和基于在NP周围形成的取代的聚（酚）的基质来接枝。特别重要的是开发这种聚合物的自限生长。我们将后功能化的薄膜，以提高选择性和抑制非特异性吸附。为了防止模板的过度生长，我们将使用绝缘NP作为模板，其配备有与目标分析物NP类似的外壳。模板去除的效率将通过电化学、扫描电子显微镜（SEM）、X射线光电子能谱（XPS）和扫描力显微镜（AFM）来跟踪。将通过区分尺寸、形状和外壳的NP批次研究再摄取过程。具有不同核的NP的使用将允许通过表面光谱在它们固定在NAIM的腔中之后区分不同的NP批次。

Assessing the presence, distribution and toxicological potential of man-made ligand shell-protected nanoparticles (NPs) becomes an increasingly urgent issue as the ability of preparing NPs with very interesting functional properties is tremendously surpassing the ability to predict toxicological hazards of those materials. It is generally accepted that toxicological hazards of nanomaterials stem not only from their elemental composition but to a very important extent from their size, shape and the chemical nature of the ligand shell. Consequently, toxicity testing involves a costly and large variety of assays including animal testing required before NPs can be used for technological application. There are no simple and cost-effective methods available for testing the presence of specific NPs in the environment.This project aims for providing a new, simple and cost-effective approach to selectively detect NPs and predict their interactions with biological materials using nanoparticle-imprinted matrices (NAIM) for NPs speciation. This concept has recently been demonstrated for the first time by the applicant for size discrimination of NPs. A matrix is formed in the presence of template NPs. After the release of the NPs, the imprinted cavities are able to selectively reuptake analyte NPs. Within the project, the approach will be significantly extended to explore selectivity towards different shells. Our work has demonstrated that NAIM should be made of thin films because this allows addressing entrapped NPs by the substrate electrode. Different chemistries will be used to obtain NAIMs in order to provide a large variability of surface groups to detect different ligand shell systems. The approaches include grafting by reduction of functionalized aryldiazonium ions around pre-immobilized NPs and matrices based on substituted poly(phenols) formed around NPs. Of special importance is the exploitation of self-limited growth of such polymers. We will post-functionalize the films in order to enhance the selectivity and to surpress nonspecific adsorption. In order to prevent overgrowing of the templates, we will use insulating NP as templates that are equipped with a shell similar to that of the targeted analyte NPs.Electrooxidation is used as primary mean for the NP detection. The efficiency of template removal will be followed by electrochemistry, scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and scanning force microscopy (AFM). The reuptake process will be studied by NP batches distinguished by size, shape and shell. The use of NPs with different cores will allow distinguishing different NP batches after their immobilization in the cavities of the NAIM by surface spectroscopy.