The Construction Of Electrochemical Aptasensor Based On Functional Porous Materials And Its Antibiotic Detection Performance

Antibiotics produced by microorganisms are widely used in clinical medicine,which can efficiently inhibit the growth of bacteria and other microorganisms.However,the excessive dependence of antibiotics leads to the antibiotic residue in river,soil,animal and plant to seriously endanger human and ecological environment.Therefore,it is of great significance to sensitive and specific method and functional materials to detect antibiotics.In this paper,two hybrid materials based on porous organic materials were designed and synthesized to construct electrochemical sensors for biosensing antibiotics.The sensing method is not only rapid response,high sensitivity and simple operation,but also can detect antibiotics in real samples,such as milk and serum.The main research contents are as follows:Firstly,porous aromatic framework(PAF)was synthesized by the Friedel-crafts coupling reaction of 2,4,6-tribromomethyl benzene and tetraphenyl ethylene.The as-synthesized PAF can be used as a platform to support Au nanoparticles(namely Au@PAF)through a toilless impregnation-reduction approach.The Au@PAF has excellent stability,high surface area,fine electrochemical activity as well as a powerful interaction toward aptamers.The Au@PAF-based electrochemical aptasensor exhibits super sensitive detection ability toward oxytetracycline(OTC)in a wide concentration range from 1.0×10^-5to 1.0 ng mL^-1with a limit of detection(LOD)of 3.19 fg mL^-1(6.93 fM).And this method has the advantages of simple operation,high efficiency and excellcent sensitivity for the accurate and rapid detection of antibiotics.Furthermore,a composite of gold nanoparticles(Au NPs),amino functionalized graphene(GO-NH₂)and covalent organic framework(COF)was designed and constructed for fabricating an electrochemical aptamersensor in the detection of chloramphenicol(CAP).The results show that Au@COF-GO-NH₂can improve the aptamer load due to the high affinity between hybrid material and aptamer.In the CAP concentration range of 5.0×10^-5?1.0 ng mL^-1,electrochemical impedance spectra have a good linear relationship with the logarithmic value of CAP concentration.The calculated LOD is as low as 16.13 fg mL^-1(49.91 fM).In this paper,two functional porous hybrid materials were successfully prepared to construct electrochemical aptasensors for detecting antibiotics.The electrochemical aptasensor realizes the sensitive and accurate detection of antibiotics with shorter detection time.It is expected that this work can provide an effective way for the preparation of novel functional porous hybrid materials and their applications in the electrochemical detection.