Preparation Of Fluorescent Polymer Nanotubes

Flourescent nanoparticles are extensively used in the biomedical sciences,including biological imaging, drug delivery and medical diagnosis, because of theirhigh sensitivity and straightforward multiplexing capability.Semiconductor nanocrystals (quantum dots) is a common fluorescentnano-materials and their emission wave-length can be tuned from the blue to the redwavelengths by changing the particle size. However, ordinary quantum dots (such asCdSe) are not suitable for biological application due to its toxicity. Therefore manyscientists focus on emission wavelength tunable organic light-emitting materials,especially the organic fluorescent nano materials. Organic fluorescent nano materials,which have wider application fields, combined with the dual characteristics andadvantages of organic fluorescent material and nano material. It is worth noting that inmany fields such as drug delivery and biological medicine, the shape of nanoparticlesis often play a decisive role. For example, rod-shaped nano particles, which of highlength to diameter ratio, can be delivered into HeLa cells through endocytosis withhigher delivery speed and efficiency compared to spherical nanoparticles. Therefore,it is of scientific and practical application significance to build one dimensionalnanosture materials with organic fluorescent material.The article adopt polymer wetting anodic aluminumoxide template to preparepolymer nanotubes, with the flourescent polymer MEH-PPV as raw material.Thespecific study is as follows:1) At first, MEH-PPV-Green and MEH-PPV-Blue were respectively preparedthrough controlling the oxidation time of MEH-PPV, with using optimized oxidationsystem of formic acid and hydrogen peroxide. Secondly, hydroxyl was introducedonto MEH-PPV molecular structure through hydrolyzing the oxidation products.Eventually, a bioactive molecules, histidine, was grafted onto MEH-PPV structure byesterification reaction.2) Polymer nanotubes were prepared by wetting anodic aluminumoxide template,with MEH-PPV and MEH-PPV-Green-histidine as raw material. The study resultssuggested that MEH-PPV-Green-histidine nanotubes exhibit good dispersion stability in acidic aqueous solution, but it is prone to gather and settle down in neutral andalkaline solution.