| Since the development of electrospinning technology,a variety of materials covering ceramics,metals,polymers and so on have been prepared,which have excellent properties such as diverse structure,high specific surface area,good air permeability,large porosity,strong ductility,multiple functions,complete performance.It has broadened the application dimension and widely penetrated into the fields of medical biology,new energy,environmental protection,catalysis,sensors,clothing materials and so on,showing outstanding value.With the continuous progress of society,people pay more attention to food quality and ecological environment safety,and the requirements for intelligent packaging and intelligent detection are becoming higher.Based on this,this paper provided new ideas for food safety detection in the research of intelligent packaging,heavy metal and antibiotic treatment,and provides scientific basis for further optimization and combination of high-efficiency heavy metal and antibiotic removal treatment technologies and research and development of new technologies with great market potential and strong applicability.In this paper,WO3/PAN nanofibers were prepared by electrospinning with polyacrylonitrile（PAN）and tungsten chloride（WCl6）as precursor.Mobile phone software,Fourier transform infrared spectrometer（FT-IR）,X-ray diffractometer（XRD）,Polymerase Chain Reaction（PCR）,PCR),gel imaging system,high performance liquid chromatography-mass spectrometry（HPLC-MS）,scanning electron microscope（SEM）and other technologies were used to characterization,smart packaging,efficient treatment of heavy metals and antibiotics were researched for applying environment,smart packaging materials were built for risk warning from the practical application point of view,safeguard consumers’ rights and interests,and further clarify the mechanism of removing antibiotics and heavy metals in urban sewage system from the molecular and cellular levels,so as to reduce the new pollutants from flowing into the ecological environment and eliminate the harm.1.preparation of WO3 nanofiber and its application in oxygen indicatorIn this paper,by sol-gel method,with PAN and WCl6 as raw materials and N,Ndimethyl formamide（DMF）as solvent,WO3/PAN nanofiber membrane was prepared by electrostatic spinning machine after dissolving and stirring to a transparent state,and many WO3/PAN nanofiber discs were cut by cutting machine as oxygen indicators.The oxygen indicator is loaded in the modified atmosphere package,and then the oxygen indicator is irradiated by ultraviolet lamp after vacuum treatment/modified atmosphere treatment into the package with oxygen-free atmosphere,so that the color of the indicator changes from light yellow to blue.Take photos with Nova5i Pro Huawei mobile phone,and use the software "Color Picker" to analyze the photos and convert them into pixel values of red（R）,green（G）and blue（B）color channels.Different colors correspond to different RGB values.If the oxygen-free atmosphere is kept in the packaging,the R value obtained by the mobile phone software remains unchanged,and once there is oxygen leakage,the R value will change greatly.The degree of gas leakage can be judged by the degree of change of the R value,so that the oxygen leakage degree of food in the transportation,storage and sales chain can be monitored throughout the whole process,which has the functionality and integrity of intelligent packaging indication and reduces the risk.2.Application of WO3 nanofibers in heavy metal removalThe nanofibers were applied to sewage treatment system,and the effects of initial concentration,dosage,reaction time,concentration and ion species on heavy metal absorption were carried out by HPLC-MS,and a series of single factor studies on adsorption performance were carried out.The results showed that nanofibers were suitable for dynamic adsorption and could efficiently remove metal ions under suitable conditions.The adsorption of solutions containing Na+ and K+ metal ions was higher than that of solutions containing Mg2+ and Ca2+.Cl-promoted significantly higher than NO3-and SO42-;Nanofibers had good reusability.By analyzing the ability of nanofiber to removed heavy metals and exploring the optimal treatment conditions of nanofiber,the removal of pollutants could be treated to the greatest extent,which was beneficial to the use of polymer materials and could provide scientific basis for the removal of pollutants.3.Application of WO3 nanofiber in antibiotic removalThrough HPLC-MS,bacterial isolation and culture and PCR,the removal of three antibiotics,resistance genes,resistant bacteria and resistance of resistant bacteria by nanofibers was studied.After being treated with nanofibers,the concentrations of the three antibiotics were 2.31 × 102～1.62×103 g·L-1,9.18×103～1.21×104 g·L-1 and 4.2×103～2.4×103 g·L-1,and the average degradation rates were increased by 2.36%,2.89%and 3.3%,respectively.After treatment,the resistance of antibiotic-resistant bacteria decreased,and the ratio of multiple antibiotic resistance of three antibiotics was 21.25%,28.75%and 17.5%.The removal rates of tetracycline resistance genes tet（A）,tet（M）,tet（W）and tet（Q）were 5.3%～17.1%,5,1%～22.3%,7.2%～20.1%and 11.4%～31.3%respectively.The removal rates of sulfamethoxazole resistance genes sul Ⅰ,sul Ⅱ,sul Ⅲand sulA were 9.2%～21.7%,8.1%～19.7%,10.2%～16.4%and 9.2%～17.9%,respectively.The removal rates of norfloxacin resistance genes qnr A,qnr D,qnr C and qnr S were 12.5%～16.6%,9.7%～12.4%,11.2%～19.9%and 12.5%～17.2%,respectively.After treated with functional materials,the number of anaerobic bacteria in Gammaprotebacteria increased and the concentration of Subgroup decreased.The results have showed that nanofibers can effectively remove the residues of antibiotics such as tetracycline,sulfamethoxazole and ciprofloxacin under suitable conditions,and reduce the resistance of antibiotic resistance genes and resistant strains in sewage treatment system.It has been further proved that nanofibers can adjust the diversity of microbial communities,reduce the potential threats of antibiotics,resistant bacteria and resistant genes in sewage to the ecological environment,which had been conducive to the improvement and upgrading of sewage treatment technology and can effectively protect human health. |
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