Novel Fluorescence Probes And The Application In Detection And Imaging

Nowadays, fluorescence sensors have attracted more and more attention because of their detection and imaging application in biology and environment. Fluorescence probes possess specific recognition to the target, and which could realize the detection by the variation of fluorescence and movement of spectra. As a consequence of the outstanding merits: real-time recognition, high sensitivity, rapid response and low cytotoxicity, fluorescence chemosensors have an increasingly significant role in the detection and imaging of biology and environment. Hence, we do some work as follows:1、A new fluorescent rhodamine B derivative as “Off-On” chemosensor for Cu2+ with high selectivity and sensitivityA novel fluorescence chemosensor containing two rhodamine B moieties per molecule was synthesized and characterized as an “off-on” fluorescent probe for the detection of copper ions(Cu2+). The chemosensor showed high selectivity, sensitivity and good repetition in sensing Cu2+, and the detection limit was as low as 38.00 n M. In addition, the chemosensor displayed low cytotoxicity and was successfully applied to living cell imaging for detecting Cu2+. Therefore, based on being environment friendly and good biocompatibility, the results offered the advantages including the detection of Cu2+ in environment and bioimaging of intracellular Cu2+.2、Water-soluble turn-on fluorescence hybrid chemosensors for Cu2+ detection and living cell imagingOn account of low solubility in water and poor stability, we grafted the organic probes to the small-sized mesporous Si O2 nanoparticals and successfully obtained excellently water-soluble and stable turn-on fluorescence hybrid sensors, which could realize the recognition for Cu2+ in water and the bioimaging of intracellular Cu2+.3、Rare-earth upconversion nanoparticals for the detection of hepatitis B virus(HBV) DNADense Si O2 coated upconversion nanoparticals(UCNPs@Si O2) with different Si O2 layer thickness(1~15 nm) were fabricated, which owned uniform morphology and good dispersity. Subsequently, a kind of nanoprobe based on luminescence resonance energy transfer(LRET) process was prepared by using the obtained UCNPs@Si O2 as energy donor and carboxytetramethylrhodamine(TAMRA) as energy acceptor for the detection of hepatitis B virus DNA(HBV-DNA) sequences. When the target HBV-DNA sequences were present, the energy acceptor TAMRA was brought close to the energy donor UCNPs@Si O2 through the complementary base-pairing reaction and thus a sandwich hybridization was formed, leading to action of the effective LRET process. As a result, this system could detect HBV DNA sequences successfully with high sensitivity and selectivity.