Abstract:
Among biosensing systems for sensitive diagnoses fluorescence enhancement techniques have attracted considerable attention. This study constructed a simple multilayered structure comprising a plane metal mirror coated with a plasma-polymerized film (PPF) as an optical interference layer on a glass slide for fluorescence enhancement. Plasma polymerization enables the easy deposition of organic thin films containing functional groups, such as amino groups. This study prepared PPFs using acetonitrile as a monomer, and the influences of washing and the output powers of plasma polymerization on PPF thickness were examined by Fourier transform infrared spectroscopy. This is because controlling the PPF thickness is vital in fluorescence enhancement. Multilayered glass slides prepared using a silver layer with 84 nm-thick acetonitrile PPFs exhibited 11- and 281-fold fluorescence enhancements compared with those obtained from the substrates with a bare surface and only modified by the silver layer, respectively. Oligonucleotides labeled with a thiol group and cyanine5 were successfully immobilized on the multilayered substrates, and the fluorescence of the acetonitrile PPFs was superior to that of the allylamine and cyclopropylamine PPFs. Furthermore, an aptamer-based sandwich assay targeting thrombin was performed on the multilayered glass slides, resulting in an approximately 5.1-fold fluorescence enhancement compared with that obtained from the substrate with a bare surface. Calibration curves revealed the relationship between fluorescence intensity and thrombin concentration of 10-1000 nM. This study demonstrates that PPFs can function as materials for fluorescence enhancement, immobilization for biomaterials, and aptamer-based sandwich assays.
摘要:
在用于灵敏诊断的生物传感系统中,荧光增强技术已引起相当大的关注。这项研究构建了一个简单的多层结构,该结构包括一个平面金属镜,该平面金属镜涂覆有等离子聚合膜(PPF),作为载玻片上的光学干涉层,以增强荧光。等离子体聚合使含有官能团的有机薄膜易于沉积,如氨基。本研究以乙腈为单体制备PPFs,通过傅里叶变换红外光谱研究了洗涤和等离子体聚合输出功率对PPF厚度的影响。这是因为控制PPF厚度在荧光增强中是至关重要的。与从具有裸露表面且仅由银层修饰的基材获得的那些相比,使用具有84nm厚乙腈PPF的银层制备的多层载玻片表现出11倍和281倍的荧光增强,分别。用巯基和花青素5标记的寡核苷酸成功地固定在多层基质上,乙腈PPFs的荧光优于烯丙胺和环丙胺PPFs。此外,基于适体的夹心试验靶向凝血酶在多层载玻片上进行,与从具有裸露表面的基材获得的荧光增强相比,导致约5.1倍的荧光增强。校准曲线揭示了荧光强度与10-1000nM的凝血酶浓度之间的关系。这项研究表明,PPFs可以作为荧光增强材料,生物材料的固定化,和基于适体的夹心分析。