Fabrication Of MOFs-based Renewable Biosensors And Their Application In Disease Detection

Zoonotic diseases pose a huge threat to human life and property due to their strong transmission and complex treatment.How to stop the spread of diseases is a key concern.Early detection is the most effective way to cut off the chain of transmission.However,due to the shortcomings such as time-consuming,expensive or complicated operation of the traditional disease detection methods,the efficiency of traditional disease detection methods is not high.Especially for some resource-poor and remote areas,the cost of disease detection is too expensive.Electrochemical biosensors can make up for these shortcomings by virtue of their characteristics.If the cost can be further reduced,it will be more conducive to the popularization of electrochemical biosensors.In this paper,three reusable electrochemical biosensors with excellent performance through interface regeneration were prepared for disease detection,thereby reducing the cost and realizing low-cost early detection of diseases.(1)An interfacial regenerative electrochemical biosensor with high sensitivity and selevity for Mycoplasma ovine pneumonia(MO)detection was developed based on metal-organic frameworks(MOFs)encapsulating and releasing probe DNA of MO.The success of the modification process was demonstrated by various characterizations.After optimization for various experimental conditions,the biosensor can detect target DNA in the buffer from 10^-10 M to 10^-6 M with a lower limit of detection(LOD)of 1.00 p M(S/N=3).In addition,the biosensor also showed good performance in diluted serum.The biosensor has simple operation steps and can be reused,which greatly saves material cost and labor cost.(2)A reusable electrochemical biosensor for tuberculosis(TB)detection was developed based on polyethyleneimine(PEI)and chondroitin sulfate(CS)two-layer anti-fouling materials.Through layer-by-layer modification steps,gold nanoparticles(Au NPs),PEI,CS and probe DNA were modified on the electrode surface.The biosensor exhibited good specificity and sensitivity.In addition,urea was used to completely separate the complementary double helix DNA strands,resulting in a biosensor that could detect TB again.In addition,we evaluated the effects of single proteins,small organic molecules and complex biological systems on this biosensor.The results showed that CS,one of the main components of the anti-fouling membrane,played an important role in the formation of the waterproof surface layer.This is the main reason for the excellent anti-pollution performance and reusability of biosensors.The biosensor not only exhibits excellent linear detection range(10^-14 M-10^-10 M)and low detection limit(LOD=0.03 f M)in buffer,but also in diluted serum.The biosensor has the characteristics of being reusable and has strong application prospects.(3)Based on MOFs loaded with signaling molecules and encapsulated with DNA,an electrochemical biosensor that can distinguish SARS-Co V-2 from SARS-Co V was developed.The prepared MOFs were loaded with signal molecules and DNA encapsulation steps,and then Au NPs and polyethylene glycol(PEG)were modified on the electrode surface through layer-by-layer modification.The results showed that the detection results of SARS-Co V-2 and SARS-Co V were completely different.The biosensor can judge the problem of false positives in the detection of SARS-CoV-2,which needs further study.