Preparation Of Fluorescent Probes Of Targeting Polymersomes And Their Preliminary Cell Labeling

Up-to-now, the cancer diagnosis depends mainly on in vitro detection procedures and such imaping techniques as ultrasonic imaging, X-ray photography, X-ray computed tomography, nuclear magnetic resonance imaging, etc. The determination and confirmation of cancers are relying on the morphology and other macroscopic characteristics of tumor tissues or ill cells, and this is usually an invasive and time-consuming process. Such procedure is definitely not suitable for early cancer diagnostics. Aforementioned imaging techniques are difficult to find the symptom of cancers at molecular level. Nevertheless, optical imaging technologies, especially fluorescence molecular imaging, possess advantages of harmlessness, noninvasiveness, super sensitivity and possibility for in vivo imaging and are believed to have the possibility to realize the diagnosis of cancers at molecular and cell levels.Polymersomes newly emerging for the past few years are kinds of self-assembly soft nano materials. Due to their unique chemical composition and construction, they have many predominant physico-chemical properties which make them very promising fluorescent probes. Our work put emphasis on preparation of fluorescent probe based on polymersomes and target lung cancer cell A549 with polymersomes. First, we summarize the development of polymersomes for the past few years, including the composition and construction of polymersomes, characterizing manner, methods of preparation and materiel loading and application of polymersomes as fluorescent probes. Second, we investigate the method of rehydration preparing polymersomes with amphiphilic block copolymer and nile red. With a series of treatments of sonication, freeze-thaw and extrusion, we could control the size distribution of polymersomes effectively in order to facilitate utilization in biology. Third, we adopt the strategy of end terminal hydroxide activation and biotin-avidin system to functionalize the surface of polymersomes, which make them generic nanoplatform. Last, we labeled lung cancer cell A549 with targeting fluorescence-emissive polymersomes as fluorescent probes and undertake the preliminary investigation of absorptive kinetics of polymersomes-cell interaction.In a word, we prepared polymersomes with amphiphilic block copolymer and nile red, then functionalize the surface of polymersomes, and complete a generic nanoplatform finally. With linkage of specific antibody, polymersomes could label lung cancer cell effectively and are believed to be new fluorescent probes.