Cell Fluorescence Imaging And Cell Toxicity Research Of Functionalized Conjugated Polymers Quantum Dots

Objective：This paper detected the cell fluorescence imaging and cell toxicity researchof functionalized conjugated polymers quantum dots, the purpose is to evaluate the ability offluorescence imaging、biocompatibility of this material. Do the basic research of manufacturecell probes，which using functionalized conjugated polymers quantum dots，in order to takeadvantage of functionalized conjugated polymers quantum dots’ biological characteristics tobuild a new endoscopy to improve diagnostic rate of early gastric cancer.Method:(1) The different concentrations (25ppm,50ppm,100ppm,200ppm)functionalized conjugated polymers quantum dots was incubated on normal human gastriccells、human gastric cancer cells12h,then used fluorescence microscopy observe cellimaging、flow cytometry detected fluorescence intensity;(2) Different concentration of thefunctionalized conjugated polymers quantum dots incubated24h、48h、72h with normalhuman gastric mucosal cells, then MTT detected cell proliferation and toxicity;(3) Differentconcentration of the functionalized conjugated polymers quantum dots incubated24h withhuman gastric cancer cells, then detected cell cycle、mitochondrial membrane potential,reactive oxygen species levels by flow cytometry. The control group was cells which wascultured by culture medium without functionalized conjugated polymers quantum dots. Weused SAS11.0software to carry out the statistical analysis.Results:(1) Cell fluorescence imaging：Fluorescence microscope with bright fieldobserved the experimental groups, the number and form of cells had no obvious differencecompared with normal cells; With dark field observed experimental groups，in the view ofeach sample we saw scattered patchy blue spot, clear image, strong fluorescence brightness, light spot number and brightness increases with the polymer concentration of quantum dots；Overlapped the images of bright field and dark field，cells shadows in light field and the bluespot in dark field light field coincided with each other. Flow cytometry showed fluorescenceintensity of each experimental group compared with the control group P<0.05, there wassignificant difference; compared the experimental groups P<0.05, there were significantdifferences. The average single cells fluorescence intensity is related to the concentration ofpolymer dots.(2) Cell viability testing: Compared with the control group, no significantdifference between the experimental group cytotoxicity (P>0.05);25、50、100ppm groups cellproliferation was positively associated with concentration of functionalized conjugatedpolymers quantum dots, the survival rate had significant difference (P<0.05);200ppm groupproliferation rate was reduced.(3) Cell cycle analysis：25、50、100ppm groups the number ofcell in G1/G0phase is decreased, in PI (S+G2/M) phase is increased, the number waspositively associated with concentration of functionalized conjugated polymers quantum dot,there were significant differences;200ppm group the number of cells in G0/G1phaseincreased, S+G2/M phase cells decreased, compared with the control group P<0.05, therewere significant differences.(4) Determination of MMP: fluorescence intensity of Rh123ineach experimental groups significantly increased and displayed a dose-dependent mannerafter the Pdots-treated, compared with control group P<0.05, there were significantdifferences.(5) Determination of ROS: each experimental group in a single cell fluorescenceintensity of DCF was higher than that of control group, compared with the control groupP<0.05, there were significant differences;25、50、100ppm group the fluorescence intensity ofeach cell is associated with the polymer quantum dot concentration, this3experimentalgroups were compared, P>0.05, is no statistical difference;200ppmgroup the fluorescenceintensity of DCF in every cell is decrease. Conclusion:(1) Functionalized conjugated polymers quantum dots is able to achieve aclear、stable cell fluorescence imaging and non-selective types of cells, indicating thatfunctionalized conjugated polymers quantum dots as cell probe has greater potential influorescence imaging fields.(2) Concentrations below200ppm solution of Pdots is no cell cytotoxicity, and to someextent, can promote cell proliferation,200ppm group reduce the cell proliferation rate, thatprove Pdots as a biological material has high security, laid the foundation for further in vivoexperiments and clinical application， provides a theoretical basis for building a newendoscope to improve diagnostic rate of early gastric cancer.(3) The functionalized conjugated polymers quantum dots promote cell proliferation rateassociated with concentration, by extending the S phase, increasing the number of polaritymitochondria, increase the amount of reactive oxygen species, such as the way to achievegrowth.