Studying On The Fluorescence Spectra Characteristics And Sterilization Effect Of Nanoparticles On Escherichia Coli

E.coli is an important indicator for the detection of water pollution and food contamination.Research on the detection and sterilization of E.coli has attracted widespread attention.In this study,fluorescence spectroscopy was used to analyze the fluorescence characteristics of E.coli,and the number of E.coli bacteria was characterized.The growth curve of E.coli was studied from two aspects of experiment and simulation,and three kinds of nanometals were studied and compared to the large intestine.Bacillus sterilization effect.First of all,this study used fluorescence spectroscopy to study the luminescence characteristics of E.coli,explored the lowest detection line of E.coli in water environment,and innovatively used fluorescence method to characterize the growth curve of E.coli.The E.coli has obvious characteristic emission peaks at 332 nm and425nm respectively;when the concentration of E.coli water solution changes,the characteristic emission peak intensity decreases with the decrease of E.coli concentration,and the lowest detection of E.coli in water.With a limit of 16 CFU/ml or less,the characteristic fluorescence peak disappeared.The intensity of characteristic peaks at 332 nm and 425 nm of E.coli below 20% concentration showed a linear relationship with the number of living organisms of E.coli.Secondly,the growth characteristics of Escherichia coli during the delayed period,logarithmic phase,stationary phase,and decline stage were characterized by using the E.coli fluorescence spectra of different culture periods.The characteristics of E.coli growth curves were obtained by using fluorescence spectrum curves.The Gompertz model was used to simulate the growth curve of E.coli.The results obtained were basically consistent with the experiment.The growth curve of E.coli at different temperatures was simulated.The higher the temperature,the shorter the delay period and logarithmic phase of E.coli.The sooner it enters a stable period,lowering the temperature can extend the delay period and the logarithmic phase.Finally,an exploratory study on the bactericidal effect of nanosilver,titanium dioxide,and nanogold on E.coli provides valuable reference for the sterilization effect of nanometals at different sterilization times,different addition amounts,and different temperatures.Fluorescence spectroscopy was used to measure the E.coli to which nanometals were added.The experimental results showed that the sterilization time and the addition amount all affected the silver nanoparticles,titanium dioxide and gold nanoparticles,and the silver nanoparticles reacted strongly to the temperature change.Titanium dioxide is less affected by temperature,and gold nanoparticles are hardly affected by temperature.After comparing the sterilization effects of the three nanometals,it was concluded that in the effect of sterilizing E.coli,nanogold>titanium dioxide> Nano silver.