Preparation And Application Of Organic Nanocrystal Fluorescent Probes

The paper is composed of the following two parts:In the first part, anthracen, perylene, triphenylene and 1-aminoanthraquinone colloids have been prepared by reprecipilation method. In comparison with the fluorescence emission spectra of colloids and molecular (in acetone solution), it indicates that colloids fluorescence spectra red shifted and easy emission. Base on the florescence emission and molecular structure theory, we conclude that these moleculars overlap each other when form particles.In the second part, we application triphenylene, perylene and 1-aminoanthraquinone colloids present three assay methods. (1) In this experiment, triphenylene colloids fluorescence emission was measured at λ ex λ. em=307/461 nm. In the optimum pH range of 7.2 to 8.3, at room temperature, enhancement of this emission can be accomplished by the addition of aluminum ion. The enhancement intensity of fluorescence was proportional to the concentration of aluminum in the range of 8.2-200 μ g/L. Its detection limits are 0.15 μ g/L. Based on this, a new quantitive method for aluminum assay presented. (2) The fluorescence decrease of colloid-CTAB in the presence of nucleic acids. Under the optimum conditions, the ratio of fluorescence intensity in the absence and presence of nucleic acids was proportional to the concentration of nucleic acids over the range 0.02-5.1 u g ml-1. Based on this, a new quantitative method for DNA assay was presented. (3) aggregate of 1-aminoanthraquinone have been prepared by reprecipitation method. The resonance light-scattering (RLS) of aggregate of 1-aminoanthraquinone is greatly enhanced by deoxyribonucleic acid in pH 6.1. There is a resonance light-scattering peak at 374 nm, and the enhanced intensity of RLS at this wavelength is proportional to the concentration of deoxyribonucleic acid. So a method of RLS for the determination of deoxyribonucleic acid is established. Under optimal conditions, the linear ranges of the calibration curves were 4.0 X 10-8~2.7 X 10-6 g/mL for Calf thymus DNA (CT DNA), 8.5X10-8~9.1X10-6 g/mL for Fish sperm DNA (FS DNA). The detection limits were 22.8 ng/mL for CT DNA and 26.2 ng/mL for FS DNA.