Design of a Novel Nanobiosensor for the Diagnosis of Acute Lymphoid Leukemia (ALL) by Measurement of miRNA-128

In this work, an aptamer-based electrochemical nano biosensor has been designed that is effective in the early detection of Acute Lymphoid Leukemia (ALL) by microRNA-128 in blood serum samples. In the design of this nanoprobe, Graphitic Carbon Nitride (G-C3N4) has been used. Urea at high temperature is used to prepare graphitic carbon nitride. G-C3N4 has a modifiable surface that can carry metals, so gold nanoparticles were placed on its sheets. Consequently, the resulted nanocomposite obtained a high surface-to-volume ratio and much higher conductivity for aptamer binding. The synthesis method of this nanocomposite is Green using vitamin C and is biocompatible. In this study, electrochemical characterization tests, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) tests and transmission electron microscopy (TEM) technique were used. The Limit Of Detection (LOD) of the nano biosensor was obtained about 0.0034 fM in square wave voltammetry (SWV). It was obtained by performing tests at different concentrations of the analyte for three times. Compared with the other works, this limit of detection is much lower and shows the high ability of the nanobiosensor to early detection of Acute Lymphoid Leukemia. Also, the designed biosensor needed a short time (about 45 minutes) to detect the miRNA-128 as symptoms of the disease. It is the first time that Au/G-C3N4 nanocomposite and this aptamer sequence are used in a biosensor together for gene detection (miRNA-128) as an electrochemical biosensor for diagnosis of acute lymphoid leukemia.