Identification and imaging of leukemia cells using dual-aptamer-functionalized graphene oxide complex

Acute lymphoblastic leukemia is the most common malignancy in children. Patient improvement completely depends on the diagnosis of acute lymphoblastic leukemia. So there is a great demand for diagnosis of acute lymphoblastic leukemia. In this study, a novel assay based on dual-aptamer (Sgc8c and ATP aptamers)-functionalized graphene oxide (DAFGO) complex was designed for the identification of Molt-4 cells (human acute lymphoblastic leukemia T-cell). This assay relies on the internalization of DAFGO complex into Molt-4 cells, but not into U266 cells, using Sgc8c aptamer as molecular recognition probe, and release of FAM-labeled ATP aptamer from the complex in the presence of high amounts of ATP in lysosome, leading to a strong fluorescence emission. Formation of DAFGO complex was analyzed by fluorometric analysis and gel retardation assay. The internalization of complex was monitored by flow cytometry and fluorescence microscopy in Molt-4 (target) and U266 cells (nontarget) with DAFGO complex. Our results showed that the developed complex was efficiently internalized into target cells and induced a strong fluorescence emission.