生物微结构光响应的调控及DNA分子识别研究

The sensitive and selective detection of biomolecules (e.g. nucleic acids) is important for clinical diagnostics, detection of genetic disorders,analysis of food and environmental pollutants, and homeland security.However, it is still big challenge to construct the simple, efficient, and sensitive biofunctional micor- or nanostructures for developping novel biosensors. In this proposal, bio-hiberarchy structure with light-responsive property will be selected as templates. The precise self-assembly of multi-functional layers (e.g. polyelectrolytes) or multi-layers containing semi-conductive nanoparticles (e.g. quantum dots) into the template are carried out. Based on the changes of the refractive index of the template by the introduction of multi-layers, the light-responsive mechanism in the template will be investigated. Since tiny amount materials can already induce the shift of resonance peak or enhancement of bio-hiberarchy structure, the sensitive and selective detection of nucleic acides (DNA) will be performed by using the bi-hiberarchy structure. The study is expected to make the microstructure keep original structure and have new function at the same time. This can provide the theory bases for exploring the cheap, simple technology, efficient and photosensitive system for biological molecules recognization.

目前构建工艺简单、高效而又能灵敏识别生物分子的功能化微纳米结构是生物诊断技术发展中富有挑战性的研究领域。本项目以具有光响应的生物精细微观结构（如蝴蝶）为模板，采用层层静电吸附自组装（LBL）的方法实现多层功能膜（如正、负电荷聚电解质）或含半导体纳米粒子（如量子点CdS）多层膜在微纳米结构中精确的自组装。根据自组装膜折射率可调控的特点，通过改变多层膜的结构和组分，研究多层膜对生物微观结构的光响应调控规律与机理。基于微量物质能够引起光敏性微纳米结构共振峰偏移或增强的原理，探索光响应生物精细微观结构对生物分子（如脱氧核糖核酸DNA）的识别机理及灵敏性、选择性。该研究有望使生物微观结构保持原有结构的同时出现新的功能，为探索价格低廉、工艺简单、高效而又光敏性的生物分子识别新体系提供了理论依据。

本研究旨在通过功能导向的自组装技术，为在生物体微观结构中大面积高效有序的自组装功能材料提供理论和实验依据，对基于生物精细结构和功能自组装体的生物分子或细胞等敏感识别进行探索。选择了天然结构（如玫瑰花瓣）为生物体精细微观结构，设计了自组装可控的超分子凝胶剂因子，大面积高效有序的复制了玫瑰花精细微纳米结构。研究了微纳米结构对生物分子或细胞等的敏感响应，探索了自组装功能金纳米粒子对DNA分子的敏感检测特性，建立了在无害光激发下原位观察纳米纤维结构对细胞粘附的感应。该研究为在易于大面积复制的生物微纳米结构上获取生物分子和细胞等的敏感检测奠定了基础。