Synthesis Of Cationic Polypyrrole And Applications For DNA Detection

Conjugated polymers (CPs) are a kind of highly efficient medium, which can transport electronic excited states. The electronic properties in CPs provide unique opportunities for chemosensory materials. In response to interactions with analytes, CPs produce informations into observable optical responses and amplifying fluorescence signals. This dissertation focused on the detection of DNA- hybridization and base pair mismatch messages by the designed water-soluble polypyrrole.N-(4-butyl-(1-methylimidazole)) pyrrole bromide (Py-Br) was designed and synthesized from pyrrole. The microemulsion polymerization with the monomer PPy-Br results in the precursor microparticle (PPy-Br). By anion-exchange method, poly (N- (4-butyl-(1-methylimidazole)) pyrrole tetrafluoroborate) and poly (N-(4–butyl-(1-me thylimidazole)) pyrrole hexafluorophosphate) microparticles were obtained. The synt- hesized monomers and polymers were characterized via 1HNMR and FTIR, respect- ively. By TEM, TGA and Conducting Text, the resultant polymer nanoparticles show the sizes, conductibity and themal stability could be changed with the anions. The water-soluble PPy-Br polymer reveals fine fluorescent in fluorescence spectrum, which provides an opportunity to develop the DNA detection. By fluorescence spectrum, detection of DNA- hybridization and base pair mismatch messages was carried out efficaciously. CD spectrum revealed the messages of PPy-Br/DNA complexes, which indicated the ds-DNA was much more stable than the ss-DNA. Herein, we also developed a new cyclic voltammetry method based on cationic polypyrrole for DNA detection.