Study On Preparation And Application Of Hemoglobin Fluorescent Molecularly Imprinted Polymer

The change of hemoglobin concentration is related to many diseases.Thus,it is particularly important to prepare a kind of material which can specifically identify and effectively separate hemoglobin.Molecular imprinting has been widely concerned due to its good adsorption capacity and selectivity.The detection of concentration is also important.The reported detection methods of hemoglobin including antigen-antibody detection method,the application of which is limited due to the high price.Thus,it is necessary to develop a low-cost method that can specifically detect the hemoglobin concentration.In this study,hemoglobin molecular imprinting polymers(MIPs)were prepared by sol-gel method.The surface of MIPs prepared in this work has uniform imprinted sites,which realizes the specific adsorption and separation of hemoglobin.Then,a method for realizing specific detection of hemoglobin was developed by organically combining quantum dots(QDs)and molecular imprinting to prepare core-shell structure MIPs with quantum dots as core.The effects of preparation and adsorption conditions of these two kinds of MIPs on adsorption and detection performances were investigated.Firstly,MIPs were prepared by sol-gel method.The polymerization was realized by mixing monomer APTES,crosslinking agent TEOS and carrier SiO2 in anhydrous ethanol.After polymerization,10%SDS+10%HAc was used as eluent for eluting the polymers,and MIPs were obtained after elution and drying.Then MIPs were used for the adsorption of hemoglobin and the results showed that both MIPs and non-imprinted polymers(NIPs)reached adsorption equilibrium at 8 h.When the initial protein concentration was 2,000 mg·L-1,both the adsorption capacities of MIPs and NIPs reached the maximum values,which were 2,331.858 mg·g-1 and 1,775.658 mg·g-1,respectively.In addition,the maximum adsorption capacity of MIPs was higher than that of NIPs,and the imprinting factor was 1.313.The adsorption process of MIPs agreed well with the pseudo-second-order kinetic model.When MIPs were contacted with Hb/Lyz and Hb/Cyt.C binary mixed solutions,the prepared MIPs showed good selectivities for hemoglobin when MIPs were used for the adsorption of Hb/lysozyme(Lyz)and Hb/cytochrome C(Cyt.C)binary mixed solutions.The prepared MIPs still showed good adsorption performance after repeating adsorption-desorption for ten times.After the preparation of MIPs,QDs were introduced to realize the specific recognition and detection of hemoglobin.ZnO@MIPs were prepared by mixing APTES,TEOS and carrier ZnO quantum dots.Then 0.5%triton—100 was used for eluting the polymers and the MIPs with core-shell structure were obtained after drying.Subsequently,the selectivity and reuse performances of ZnO@MIPs were investigated.It was found that ZnO@MIPs still showed good selectivities for hemoglobin when they were used for the adsorption of three Hb/Bovine Serum Albumin(BSA),Hb/Cyt.C,Hb/Lyz binary mixed solutions.Finally,the results of reusability study of ZnO@MIPs showed that.ZnO@MIPs still had good fluorescence response after repeating adsorption-desortpion process for ten times.