Design And Synthesis Of Novel Water-soluble Conjugated Polythiophene For Biological Sensor

The novel water-soluble conjugated polymer because of its excellent ability to capture light and optical signal amplification which aroused researchers'wide attention in the field of biological medicine.In resent years,polythiophene derivatives have been investigated and commonly used conjugated materials,especially in biological chemical sensing,cell imaging and other organic electronic devices.In the paper,we developed a simple and rapid method for the screening of photosensitizer antimicrobial activity and synthesized polythiophenes?PTP and PTEG?with different types of charge.The physical and chemical properties and applications in the field of biological medicine have carried on the preliminary study.The main research contents are as follows:1.Two kinds of conjugated polythiophene with different charges were designed and synthesized,respectively for side chain ends with the carboxyl group of anionic polythiophene?PTP?and consists of oligoethylene glycol?OEG?functionalized cationic polythiophene?PTEG?.The physical and chemical properties have been studied.The PTP aqueous solution's colour,UV-visible spectra and fluorescence intensity have changed which induced by conformation change of the backbone.PTP because of the protonation of carboxyl groups and tertiary amine groups led to its pH–responsive property.The OEG side chain of PTEG would improve its water solubility,biocompatibility and eliminate the nonspecific interactions with biological macromolecules.Compared with the PTP/DNA/Gd³⁺complex,the average hydrodynamic radius of PTP/CO₂/DNA/Gd³⁺system becomes bigger.The fluorescence emission intensity of PTEG has changed significantly in THF/H₂O mixed solution of different volume ratio,reflecting its salvation effect.2.A new simple,rapid and high-throughput method for PACT photosensitizer antimicrobial activity screening by only a cationic polythiophene?PMNT?has been proposed.The cationic polymer PMNT tightly covered on the surface of E.coli by electrostatic interactions and hydrophobic interactions,resulting in fluorescence quenching.The fluorescence quenching efficiency can be quantitatively determine the amount of E.coli,and combined with microplate reader to realize the high-throughput screening of antimicrobial photosensitizer.This method not only can undertake photosensitizer antimicrobial activity of high-throughput screening,but also the discovery of novel photosensitizer materials has an important guiding significance.