Preparation Of Nonmaterials And Their Application In Biosensor And Biodetection

When the size of some substances decrease to nanometre scale, they will show many special properties owing to their quantum confinement effect, surface and interface effect, small size effect and macroscopic quantum effect, which will be widely used in electronic science, material science, optics and biology. Recently, nanomaterials are more and more attractive because of their application in biosensor and biodetection. In this thesis, a biosensor based on synergistic action of carbon nanotubes and ZnO particles was prepared; we composed quantum dots of good biocompatible by ultrasonic-assistant method; we marked the polymer by quantum dots, observe its distribution in the body of mice, analyzed it metabolization. The details are as follows:1. Because of the catalysis of carbon nanotubes to H2O2 and the high iso-electric potential of ZnO nanopaticles, we prepared a glucosesensor based on the synergistic action of these two kinds of materials. By using nanomaterials, the performance of the sensor was remarkably improved. This sensor can provide an ideal microenvironment for enzyme and prevent the leakage of enzyme. The sensor can detect the glucose in solution with high sensitivity, good repeatability and anti-interference.2. We prepared CdSe and CdSe/CdS quantum dots in aqueous solution using ultrasonic-assistant method. These quantum dots appeared good water-solubility and biocompatibility by linking mercaptoacetic acid. These quantum dots can be connected to biomolecule such as antibody, protein, DNA, which will show large potential application in immunofluorscence and biological molecular marking.3. We connected CdSe/ZnS quantum dots to polymer molecular poly-PTX as fluorescence labels, analyzed the size, pattern of the marked polymer by particle sizing systems, TEM and so on. Then we injected the polymer solution to the body of mice, made the frozen section of the tissues, observed the distribution of the polymer by a high resolution fluorescence microscope. We analyzed the preliminary target of the poly-PTX and its metabolization in mice's body, the results showed that the quantum dots are perfect fluorescence labels of high efficiency, low toxicity and long-time stability. We made a basic exploration of the application of quantum dots in biological imaging.