Application Of Heavy Metal Complex Photoelectric Functional Materials In Biochemical Analysis

Electrochemical biosensor has the advantages of easy operation,high sensitivity and low consumption,and has a very important role in the diagnosis of related diseases and environmental testing.The most commonly used method for monitoring electrochemical signals is chronocoulometry,whic h can quantitatively determine the amount of electroactive material or surface active material adsorbed on the electrode surface,and is easy to obtain experimental data,excellent signal to noise ratio.In this paper,electrochemical biosensor was used to detect adenosine in this method.Photoelectrochemical analysis as a branch of electrochemistry,and now gradually developed.As a new type of analysis and detection method,its optical signal and electrical signals are separated,so the background signal interference is smaller than other methods,so it will be more and more widely used in the field of analysis and detection.The sensitivity of the photoelectric sensing system depends on the photoelectric conversion efficiency of the material,so it is a key problem to design and develop a new type of high efficient material.Based on the design of high efficient photoelectric materials,this paper designs and synthesize efficient iridium complexes by introducing photosensitive group iridium complexes,and study their photoelectric properties.Combined with the signal amplification of nanomaterials,a new method of high selectivity and high sensitivity photoelectric sensing is established for the detection of biologically active molecules.The main research work includes the following contents:?1?A label-free and efficient electrochemical aptasensor was developed for adenosine detection by integrating molecular recognition and its triggered strand-replacement DNA polymerization and RC A signal amplification system.The autonomous replication/nicking process can produce a large number of cleaved fragments with the initiation of a few target adenosines,which then act as the primers to initiate the reaction of the HC R for realizing the capture of numerous electroactive indicators Ru?N H3?63+,thus inducing significant enhancement of the CC signals.By combining above cascade dual signal amplification effects,this novel sensor exhibits high sensitivity with the detection limit down to 0.032 nM.?2?A new photoelectric material [Ir?C_L??hpba?₂]PF₆?Ir-1?was synthesized by using coumarin-L?C_L?as the main ligand and 4-?2-pyridyl?benzaldehyde?hpba?as the auxiliary ligand.The UV-visible absorption,fluorescence spectra and photoelectric properties were studied.The results show that Ir-1 has strong absorption at 450 nm.When oxygen is used as the electron acceptor,the optoelectronic material can produce a stable reduction current.When the oxygen,triethanolamine,ascorbic acid as electron donor acceptor were investigated,by contrast,ascorbic acid as electron donor,the threshold voltage is-2 V,the photocurrent is stable,and the e dark current is small.And finally a photoelectrochemical biosensor for the detection of DN A prepared by using it as a signal substance exhibits a high sensitivity.Under optimal conditions,this biosensor detection limit is as low as 9.0 fmol L-1?3??.?3?A new photoelectric material [Ir?C₆?-2?dppz?]PF₆?Ir-2?was synthesized by using coumarin-6?C₆?as the main ligand,dppz as the auxiliary ligand.The UV-visible absorption,fluorescence spectra and photoelectric properties were studied.The results show that Ir-2 has strong absorption at 480 nm.When the oxygen is used as an electron acceptor,a stable reduction current is obtained.Compared with the bias voltage,when the voltage is 0 V,the detected photocurrent is large and the dark current is low when the light is off..When the oxygen,triethanolamine,ascorbic acid as electron donor acceptor w ere investigated,by contrast,oxygen as electron donor,the voltage was 0 V,the photocurrent was the largest and the dark current was small.