Self-circulating electrochemiluminescence chip for sensitive detection of circulating tumour nucleic acids in blood

Abstract

Circulating tumour nucleic acids (CTNAs), cell-free nucleic acids released from tumour cells, have been employed as potential markers for the diagnosis and prognosis management of tumours. It is important to develop highly sensitive and reliable methods for the detection of CTNAs. Herein, a self-circulating electrochemiluminescence (ECL) chip was constructed for recognizing the point mutations of CTNAs in serum. This strategy relies on a magnet-controlled self-circulating chip for enrichment of CTNAs in blood samples, and autologous blood transfusion was performed for feedback. Meanwhile, the strategy of base stacking was employed as an effective indicator for the point mutation detection of CTNAs. Furthermore, an amplified ECL assay was employed as a highly efficient signal generation mode, and a low detection limit of 100 amol and desirable specificity were achieved. The performance evaluations for the analysis of clinical CTNA samples indicated that the self-circulating ECL chip reliably responded to CTNAs from the blood. Hence, this platform satisfied the strict clinical requirements for CTNA detection and thus has the potential to serve as a new paradigm for liquid tumour biopsy.