Studies On Tumor Markers Detection Based On Enzyme Cyclic Technologies

In recent years, the incidence rate of cancer is increasing, more and more peopledied due to cancer, it has become a very serious threat to human health. Due to the lackof sensitive and accurate detection methods of early lesions of tumor, and the price ishigh, the operation is complex of available methods.So it has important research valueto find higher performance and more simple methods for the prevention,diagnosis,treatment and curative effect observationtion of tumor.This paper usesBiological barcode probes with core-shell structure and SERS activity,nanotechnology, RCA cycle enzyme technology, to amplify the detection signal.Through the method of surface-enhanced Raman detection, electrochemical detectionmethods, we achieve high specificity and high sensitivity detection of tumor cells,proteins, genes and biological activity of tumor markers of small molecules. Thefollowing is the content of the paper:1. We use the AuNPs which the DNA modified with CdS aer fixed on as theprobes. Based on the double-stranded-specific nuclease having high selectivity, it canidentify and cut the full matched double-strand DNA, RNA hybridization/DNA thedouble-stranded DNA, the DNA of double-strands. So that the ablity of cutting andspecific selection of the DSN can release the bio-barcodes into the solution.Nanoparticles through biological barcode amplification fixed CdS, combined with acationic anodic stripping voltammetry (ASV) pre-enrichment technique significantlyimproved detection sensitivity. The sensor can also be applied to detection of a samplecontained in the mRNA. Application of this detection method can achieve highsensitivity and mRNA selective measurement to obtain a linear detection range ofmRNA is5.0×10-16~1.0×10-10M. the linear correlation coefficient R2=0.997, the detection limit is1.0×10-16M (3σ) using the sensor is below the detection limitobtained in many times. While the selectivity and reproducibility of the sensor wasstudied by the sensor, and can analyze the detection of mRNA.2. Chapter utilizes the bar code technology and bio-enzymatic amplification cycle,surface enhanced Raman technology to design a highly sensitive detection method fordetection of thrombin. The chapter constructed a novel DNA molecule cyclic signalamplification biosensors, the surface-enhanced Raman spectroscopy detection methodsapplied to DNA amplification cycle. Regard the core-shell structure as signalingmolecules and the substrate enhancing Raman signal and synthetize the Raman signalprobes carrying a large number of Raman signals molecules fixed on the Core-ShellStructure. In the presence of target DNA, causing DNA double loop and rolling circleamplification reaction amplification reaction, resulting in a large number of repeatsequences of DNA containing long chain, with Raman probes, enabling the detectionof circulating DNA amplification and further verified by detecting thrombin andversatility of the method. The linear range for the detection of thrombin concentration1.0×10-9~1.0×10-5M, wide linear range, detection limit of1.0×10-10M (3σ). Themethod is easy to synthesize, simple operation, high sensitivity in the detection oftumor marker protein and good selectivity in other areas,it has broad applicationprospects.