The Construction And Application Of Biomimetic Polymer Nanochannel In Chemical And Biological Sensor

Following the evolution of nature rules since ancient times, all kinds of life almost achieved perfect evolution process of intelligent control after one hundred million years of breeding. Learning from nature, the development on life science is the eternal subject of scientific research. There are three types of membrane receptors in life system, including ion channel receptors, G-protein coupled receptors(GPCRs) and enzyme coupled receptors. The specific recognition and transmission mechanism in the cell process play important roles in the process of ionic conduction and basic molecular biology. Using comprehensive research method to simulate functional structure of living organisms will develop kinds of potential applications of specific response intelligent nanochannels and have important value of basic research in many fields, such as in sensing, analysis and drug release. Just under this research background, the present dissertation dedicated to the study in the design and development of some biomimetic nanochannels materials with specific shapes and functions. Inspired by the specific recognition and selective transport properties of biological ion channels, we did these works in consideration of the shape and the chemical composition of nanochannels. On the one hand, multi-channel PET films bombarded with heavy ions were used to produce conical nanochannels. On the other hand, different responsive groups were modified into the nanochannels to realize intelligent control in specific recognition and selective transport of ions or molecules. These studies lay solid foundation for the application of functional nanochannels in sensing, analysis and drug release fields, and the primary contents of the dissertation are as follows:1. By fabricating asymmetric structure conical shape nanochannels and designing responsive DNA molecular sequences to silver ion, we had realized responsive regulation of silver ions by the biomimetic ion channels in the certain concentration range. Such a system depended on the configuration changes of silver-ion-induced DNA molecule, which transformed from linear scattered and disordered state into a hairpin-like structure and consequently changed the effective pore size of synthetic nanochannels. It has brought a new design idea for applied research of nanochannels in sensing, analysis, drug release, and other fields.2. Based on the preparation of asymmetric structure of the conical polymer nanochannels and modification with DNA molecules into the as-prepared nanochannels to introduce responsive biological molecules, we fabricated biomimetic intelligent nanochannels regulated by adenosine and adenosine deaminase. After gold was sputtered onto films the specific sequences of DNA with sulfhydryl group were modified onto the inner wall of the nanochannels by Au-thiol interaction of chemical modification. The selective switch of functional nanochannels can be realized by treating with adenosine and adenosine deaminase appears alternately. After modification with DNA, there is an obvious decline about the current of nanochannels. In this case, ion transport has a significant close. While treated with adenosine, the nanochannels will be open. Treated with adenosine deaminase, the nanochannels are closed again.3. On the basis of conical asymmetric single nanochannel, inspired by ATP-binding cassette(ABC) transporters we construct a functional biomimetic artificial nanodevice which gated by ATP. Biological molecules will be introduced into the nanochannel to respond after the as-prepared asymmetric nanochannel was modified with responsive DNA. After gold-sputtering the specific sequences of DNA with sulfhydryl group was modified onto the inner wall of the nanochannel by Au-thiol interaction of chemical modification. After modification with DNA, there is an obvious decline about the current of this nanochannel. In this case, ion transport has a significant close. While treated with ATP the nanochannel will be open. This work, provides a new method for further monolayer self-assembly modification by combining nanochannel and biological materials, and also provides a new research platform for the development of biosensor.