DETECTION OF A CLINICALLY RELEVANT TP53 GENE MUTATION USING DNA LABEL-FREE BIOSENSORS

摘要

The development of piezoelectric and optical DNA-based sensing for the detection of point mutations of the TP53 tumor suppressor gene is presented. The sensing is based on the hybridization reaction between the immobilized probe and the target in solution. The mutation is detected since differences in the hybridization signal can be detected when the probe hybridizes the fully complementary or the mutated sequence. The immobilization chemistry is performed by thiol-dextran-streptavidin coupling and then the biotinylated probe is added. On the gold surface of the quartz crystal used for piezoelectric sensing, the specific probe sequence is immobilized, while the sensor chip of the optical device BIACORE X was modified by immobilizing, on the two flow cells, two different probes, differing only in one base. One probe is the same as in the piezoelectric sensor and the second probe contains the sequence carrying the mutation of interest. The hybridization reaction with two different target sequences (fully complementary and mutated) was performed. The analytical parameters of the systems were studied.