The Research Of Electrochemical Cytosensor Based On Aptamer Functionalized Nanoprobe

Leukemia is a class of malignant clonal hematopoietic stem cell disease, and is one of the top ten high incidence of malignant tumors in our country. Rapid and sensitive detection of leukemia cells, for timely diagnosis and effective treatment of leukemia has a very important significance. Electrochemical cytosensor, with its good selectivity, high sensitivity, low cost and rapid detection, has become one of the most powerful tools in medical research. The introduction of aptamer as target recognition molecule into electrochemical cytosensor, can achieve the goal of significantly improved detection specificity.In this paper, based on the above research background, we use aptamers, nanomaterials and electrochemical sensing technology to build new electrochemical cytosensors. Content is as follows:1. Aptamer-based competitive strategy for the ultrasensitive electrochemical detection of leukemia cellsIn order to achieve the ultrasensitive detection of leukemia cells, we constructed an aptamer-based competition electrochemical cytosensor. The cytosensor which utilized the unique structure and specific target recognition of the aptamers, and the competitive strategy, had high specificity and sensitivity. Meanwhile, with the dual signal amplification method:using Fe3O4 magnetic nanoparticles as carriers to load gold nanoparticles and AuNP-catalyzed silver deposition, the electrochemical detection sensitivity had been further improved. The electrochemical cytosensor exhibited a wide linear response to leukemia cells ranging from 1.0×102 to 1.0×106 cells mL-1 with a detection limit of 1.0×102 cells mL-1. This simple and economical electrochemical cytosensor can achieve ultrasensitive detection of clinical sample leukemia cells, which can provide accurate and reliable test results for the clinical diagnosis and treatment of leukemia.2. Electrochemical and colorimetric detection of leukemia cells using a competitive cytosensor based on aptamer and hemin/G-quadruplex DNAzymeWe constructed an aptamer and hemin/G-quadruplex DNAzyme-based competitive cytosensor, in order to achieve the simultaneously electrochemical and colorimetric detection of leukemia cells. The cytosensor which utilized the unique structure and specific target recognition of the aptamers, the catalysis of the HRP-mimicking hemin/G-quadruplex DNAzyme, and the competitive strategy, had high specificity and sensitivity. The electrochemical cytosensor exhibited a wide linear response to leukemia cells ranging from 1.0×102 to 1.0×107 cells mL-1 with a detection limit of 1.0×102 cells mL-1. This new electrochemical cytosensor has the advantages of simple, rapid, sensitive and accurate, will provide a new approach for the detection of leukemia cells, and will provide effective help for the diagnosis and treatment of leukemia.