Construction Of A Sensor Based On MOF Nanomaterials For The Detection Of DNA And Cu²⁺

Electrochemical luminescence is a perfect combination of electrochemistry and spectroscopy.It not only has the advantages of good environment,high luminosity,wide dynamic range and simple device requirements,but also has the characteristics of simple electrochemical method,stable,practical and low background signal.In addition,fluorescence analysis is also widely used in environmental and medical diagnosis due to its high sensitivity,simple use and real-time performance.Because of their special physical and chemical properties,nanomaterials have been widely used in electrochemical luminescence and biofluorescence research in recent years.However,among many nanomaterials,the materials with electrochemical luminescence and fluorescence characteristics are relatively rare.Based on this,Ru MOFNSs was synthesized by solvothermal method using Ru（dcbpy）₃²⁺as the organic ligand and metal ion Zn²⁺as the central ion.The synthetic Ru MOFNSs has the optical properties of strong ECL and FL signals.Therefore,this paper developed an ECL sensor and a fluorescence sensor based on Ru MOFNSs nanomaterials for the detection of DNA and Cu²⁺.The main contents are as follows:1.Ru MOFNSs,MoS₂NS and Au NPs were synthesized by solvothermal method,ultrasonic assisted liquid phase stripping and sodium citrate reduction of chlorauric acid.And then adopt the method of layer upon layer modification should be modified to the surface of glassy carbon electrode,constructed a Mo S₂NS/Au NPs/Ru MOFNSs/GCE ECL sensors.In addition,the 5’end of P-DNA was labeled with amino group,and the3’end was labeled with tetraferrocene.The high quenching efficiency of tetraferrocene on Ru MOFNSs ECL was used successfully for sensitive detection of target DNA.At the same time,Mo S₂NS can specifically adsorb single strand properties,after adding T-DNA,P-DNA and T-DNA hybridization off the electrode surface.When tetraferrocene is near Ru MOFNSs,the ECL signal decreases.When tetraferrocene was far away from Ru MOFNSs,the ECL signal was recovered.The ECL sensor value can be realized according to the ECL signal change from 1×10^-11-1×10^-6 M linear range of T-DNA quantitative detection sensitivity,detection limit of 0.016 p M.The experimental results show that the Mo S₂NS/Au NPs/Ru MOFNSs/GCE modified electrodes in 50%of plasma samples ct DNA detection applications have a certain anti-interference,measured by standard addition method of three experiments recovery was98.60%～101.35%,the relative standard deviation（RSD）ranged from 0.91～2.53%,indicating that the electrochemical luminescence sensor could be used for the detection of ct DNA in biological samples.2.We synthesized a specific recognition molecule,AE-TPEA[N-（2-aminoethyl）-N,N’,N’-tri(pyridine-2-methyl-ethane-1,2-diamine].This functional organic molecule can specifically cooperate with Cu²⁺to form stable complexes and improve its selectivity to other metal ions.Using another optical property of Ru MOFNSs--fluorescence,combined with AE-TPEA’s specific recognition of copper ions,a fluorescence sensor for Cu²⁺sensitive detection was successfully developed by combining Ru MOFNSs with AE-TPEA through amide reaction as a fluorescence probe.When Cu²⁺was added into the reaction system,the fluorescence of Ru MOFNSs coupled with AE-TPEA was quenched.The method is simple,sensitive,efficient and unmarked.The fluorescent sensors can be realized from 1×10^-12-1×10^-6 M linear range of Cu²⁺quantitative detection sensitivity,detection limit of 0.198 p M.The experimental results show that Cu²⁺has good selectivity and anti-interference in the application of the fluorescence sensor based on Ru MOFNSs@AE-TPEA in the detection of water samples in ponds with dilution of 100 times.The recoveries rate of the added sample was 97.43%～101.48%,and the relative standard deviation（RSD）were 0.92%～1.53%,which showed that the fluorescence switch could effectively eliminate the influence of background interference substances in pond water,and was used for the detection of Cu²⁺in actual sample pond water.This shows not only its potential environmental applications.It also expands the practical use of Ru MOFNSs@AE-TPEA.