Preparation Of Polymer Dots And Carbon Dots And Their Application Research As Fluorescent Probe

Currently, semiconducting polymer nanoparticles, which possess π-conjugated structure have become a rising star in nanomaterials family due to their fascinating performance as fluorescent probes. Pdots are superior to conventional organic dyes and semiconductor quantum dots (QDs), because of their small size, high fluorescence brightness, great photostability, steady and fast emission rate, nonblinking and nontoxic features. In recent years, Pdots have provided powerful tools for a variety of applications such as bioimaging, in vivo imaging, single-particle tracking, biosensing, drug delivery.Furthermore, as a new member of the carbon nanomaterial family, carbon dots (C-dots), with a size of less than10nm1have been receiving considerable attention in the last decade, owing to their advantages such as water solubility, resistance to photobleaching, low toxicity, high chemical stability, and low environmental hazard. The fascinating properties make them promising candidates for many exciting applications in imaging and biochemical.Based on the relevant theories, this work mainly studied the preparation of Pdots from poly[2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene-vinylene], the synthesis of C-dots from green product potatoes, and the applications of those nanoparticle as fluorescent probe. This paper includes following three parts:(1) A simple and effective method has been reported to prepare conjugated polymer nanoparticles (Pdots) that show high fluorescence from MEH-PPV. The QYs of the as-obtained Pdots is32.37%. The FL intensity of Pdots can be quenched by the successive addition of Fe3+with good selectively. Additionally, the as-obtained Pdots were applied to imaging of the Hela cells, exhibiting low cytotoxicity and excellent biocompatibility.(2) A simple, low cost, and green method was developed for the synthesis of water-soluble and well-dispersed fluorescent carbon nanodots (CDs) via one-step hydrothermal treatment of potato is reported. The as-prepared CDs shows strong blue fluorescence, with a quantum yield up to15%. We further explored the use of CDs as a novel sensing probe for label-free sensitive and selective detection of Fe3+, which is based on the strongly fluorescence quenching due to the complex formed by CDs and Fe3+with a detection limit as low as0.025μmol/L, and different concentration corresponding to distinct sensitivity while the linear ranges are1.0～5.0μmol/L and5.0～50.0μmol/L, and the corresponding linear equations are y=0.002+0.018×c and y=0.04+0.008×c respectively. The recoveries of the spiked water samples are93.7～101.5%. Therefore, the as-prepared CDs can meet the requirement for monitoring Fe3+in environmental samples.Highly blue fluorescence carbon dots were synthesized by one-step hydrothermal treatment of potatoes. The as-obtained C-dots have been applied to bioimaging of Hela cells, which shows their excellent biocompatibility and low cytotoxicity. The results exhibit that C-dots are promising for real cell imaging applications. Besides, the carbon dots can be utilized as a probe for sensing phosphate.