Application Of Two Functional Nanomaterials In The Detection Of Thiram Pesticides And The Treatment Of Breast Cancer Cells

There is a large population engaging in agricultural production,and the usage of pesticide is indispensable in the practice of modern agricultural production.However,with the large-scale use of pesticides,the problem of pesticide residues has become increasingly in actual production process,which has caused serious environmental pollution,and even causing various diseases,thereby causing damage to the ecological environment severe and human health.Functional nanomaterials（FNM）have unique optical,electrical,magnetic and other properties,and have attracted the attention of researchers in the fields of pesticide residue detection,anti-tumor,antibacterial,and antiviral,and have become one of the current research hotspots.Based on the synthesis of functional nanomaterials such as gold nanoparticles（Au NPs）and mesoporous manganese ferrite nanoparticles（m Mn Fe₂O₄ NPs）,a new method for pesticide residue detection based on Au NPs and a new technology for breast cancer cell treatment based on m Mn Fe₂O₄ NPs were established.The contents are as followed:1.Au NPs and 4-aminophenylthiol（4-ABT）modified Au NPs were synthesized by a two-step seed-mediated method using trisodium citrate,hydroxylamine hydrochloride and 4-ABT as reagents（Au NPs@4-ABT）.Transmission electrons microscope（TEM）results showed that the average diameter of Au NPs was 63 nm,respectively.Based on the changes of the ultraviolet-visible spectrophotometry（UV-Vis）intensity of Au NPs before and after the addition of Ag⁺and thiram,a new sensor for rapid and highly sensitive detection of thiram was established.The method for thiram detection could be finished within 15 min,with the detection limit of 0.04μM in a linear range of 0.05-2.0μM.Furthermore,this sensor could be used for thiram detection in apple and soil sample by the spiked tests.Generally speaking,the method proposed here was relatively simple to operate,and was promising to be used for the rapid on-site detection of thiram.2.m Mn Fe₂O₄ NPs were synthesized by one-pot method from anhydrous sodium acetate,ethylene glycol,manganese chloride tetrahydrate and ferric chloride hexahydrate.Then artemisinin（ART）was loaded into the pores of m Mn Fe₂O₄ NPs.Finally,m Mn Fe₂O₄@ART was coated with human breast cancer cells（MCF-7）membrane by ultrasonic method to form the bionic nanodrug delivery system m Mn Fe₂O₄@ART-MCF-7.The characterization results of high-resolution transmission electrons microscope（HRTEM）and dynamic light scattering（DLS）showed that the average sizes of m Mn Fe₂O₄@ART-MCF-7 was 234.9 nm with good dispersion in water,PBS and cell culture medium solution.The characteristic proteins of MCF-7 membrane were verified by polyacrylamide gel electrophoresis（PAGE）and western blot（WB）.It was found that m Mn Fe₂O₄@ART-MCF-7 and MCF-7 membranes had similar protein profiles and retained adhesion molecules for specific recognition.Hemolysis test showed that m Mn Fe₂O₄ NPs and m Mn Fe₂O₄@ART-MCF-7 had good biocompatibility.The antitumor effects of m Mn Fe₂O₄ NPs,ART and m Mn Fe₂O₄@ART-MCF-7 were evaluated by MTT assay and found to have good cytotoxicity.On this basis,MTT assay and confocal laser scanning microscope（CLSM）assay were used to evaluate the targeting effect of m Mn Fe₂O₄@ART-MCF-7,and it was found that m Mn Fe₂O₄@ART-MCF-7 possessed a good cell targeting effect.The results of this study had certain reference value for the development of new targeted anticancer drugs.