Electrochemical biosensor for detection of BCR/ABL fusion gene based on isorhamnetin as hybridization indicator

A facile electrochemical DNA biosensor using isorhamnetin (ISO) indicator for detection of the sequence-specific detection of BCR/ABL fusion gene related to chronic myelogenous leukemia was developed. Results revealed that ISO bound to DNA via the intercalative binding mode with binding number of 2 and binding constant β = 13.2. In the simulated interference background system, the block action of proteins in serum resulted to the increase of peak current difference between the probe modified GCE and after hybridization with target sequence. Under the optimal experimental condition, the proposed method could respond to target concentrations with a linear calibration range from 10 pmol L−1 to 500 nmol L−1, with a detection limit of 3 pmol L−1. This biosensor exhibited high sensitivity and selectivity, and was successfully used in determining the BCR/ABL fusion which was added in simulated interference background system with a relative standard deviation (n = 6) <5.5%. This new biosensor served as a significant step toward the practical application in clinical diagnosis and prognosis monitor.