Construction Of Electrochemicalluminescence Sensor Based On Metal Nanomaterials And DNA Amplification Technology

At present,many malignant diseases are threatening human life around the world and some of them will even develop into cancer.Therefore,accurate detection of different tumor markers is very important for the treatment of cancer.MiRNA,as a class of endogenous non-coding RNA,which plays a regulatory role in many functions of the body and is expected to become the latest biomarker.Intracellular hydrogen peroxide is involved in regulating a variety of biological processes,so it is also a new biomarker.Sensitive detection of biomarkers could provide a promising method for the prevention and treatment of human diseases.Biosensor has good biocompatibility and is widely used in the detection of various biomarkers.Metal nanomaterials organically combine the excellent characteristics of metallic materials and nanomaterials.Reasonable use of its catalytic or optical properties to detect tumor markers will achieve better effect in cancer prevention.DNA signal amplification technique has attracted much attention because of its simple and mild reaction conditions and high amplification efficiency.Therefore,combine the metal nanomaterials and effective DNA signal amplification technology could be used to introduce electrochemicalluminescence sensor in order to detect miRNA or intracellular hydrogen peroxide.This is of great significance for the study of cell biology and pathology.This paper is divided into the following parts:?1?The DNA signal amplification technique was preliminarily studied,an environmentally and sensitively method for the detection of miRNA was designed.Ru?bpy?₃²⁺-functionalized metal organic framework materials were prepared by hydrothermal method.After adding a small amount of mercury ions,the framework of the material was disassembled and a large amount of Ru?bpy?₃²⁺was released from the framework,generating strong electrochemicalluminescence signal.Once the target miRNA is added,the two hairpin probes will undergo a hybridization chain reaction on the sensing surface and form double strand DNA on the sensing surface.An electrochemicalluminescence sensor was constructed based on the above principles to quantitatively detect the target,so as to sensitively detect miRNA.?2?Combine metal nanomaterials with low-cost paper microfluidic control,a paper based electrochemicalluminescence sensor was designed,which in order to sensitive detection of intracellular hydrogen peroxide.The electrochemicalluminescence technology,signal amplification strategy of metal nanomaterials and the inhibition of ferrocene on luminescent group were combined in an experimental system.Gold nanoparticles were loaded onto the ruthenium@silica nanomaterials to obtain stronger optical signal.The ferrocene molecule then inhibits the electrochemicalluminescence signal,resulting“signal-off”.AuPd nanoparticles catalyzed intracellular hydrogen peroxide to generate hydroxyl radicals,which could break the DNA strand.Finally,ferrocene molecules leaved the system and“signal-on”.The above mechanism can be detected the intracellular hydrogen peroxides.