Preparation Of Fluorescent Conjugated Polymers And Its Nanoparticles And Applications In Detection Of Al³⁺

Owing to their large π-conjugated backbones and delocalized electronic structure, conjugated polymers (CPs) with large fluorescence absorption coefficient, high fluorescence quantum yield, good stability and excellent biocompatibility, have attracted more and more attentions in bioscience field. Meanwhile, π-π* electronic conjugated structure on the main chain provided a path for electrons and electron holes transfer, so the conjugated polymers have the advantages of semiconductor. Due to their easy synthesis, tunable properties and less toxicity and more biocompatibility, nanoparticles based on fluorescent conjugated polymer have become another hot topic followed by conjugated polymers. Herein, preparing fluorescent conjugated polymer nanoparticles by reprecipitation method with fluorescent conjugated polymers could combine the advantages of the both, which show great potential in the future.There is an abundant of Al3+ metal ion in the nature and human body. Aluminium is the third most prevalent metallic element in the earth. And it is a common metal and frequently used in our daily life. The detection of aluminum is necessary due to its potential toxicity and extensive application in packing materials, clinical drugs, food additives and water purification et al. The main contents of the paper as follows:(1). Conjugated polymers were synthesized by Wittig and Wittig-Horner reaction, and characterized by 1H NMR, IR and GPC. The effects of reaction parameters on molecular weight were also investigated. The Al3+ probe was synthesized by Schiff base reaction, and then characterized by 1H NMR, IR.(2). The UV-vis absorption spectra and one-photon fluorescence emission spectra of CPs in different solvents were studied, fluorescence quantum yields were calculated by reference method.(3). The selectivity and sensitivity of the probe for Al3+ were investigated, then the effects of doping fluorescent CP on the probe and Al3+ were also studied. The results indicated that the probe could specifical detect Al3+ with excellent sensitivity. Besides, the fluorescent properity and the sensitivity were enhanced by doping fluorescent conjugated polymer.(4). The conjugated polymer nanoparticles were prepared by reprecipitation method with fluorescent CPs, the influences of molecular weight on diameter, morphology and fluorescence properties were investigated.