A novel LiSmZrO3 perovskite-amplified interferon gamma-sensitive electrochemical tuberculosis aptasensor

Abstract

• IFN-γ aptasensor with LiSmZrO 3 perovskite nanomaterial as a novel sensing platform. • LiSmZrO 3 perovskite material exhibits excellent signal amplification properties. • Detection based on the conformation transformation of the MB-hairpin aptamer. • Aptasensor was successfully adopted to determine IFN-γ in different media. • The IFN-γ electrochemical aptasensor showed excellent analytical capabilities. Tuberculosis (TB) is a viral disease caused by Mycobacterium tuberculosis , which poses a significant threat to human life and health worldwide, causing millions of deaths each year. A key biomarker for diagnosing TB is interferon-gamma (IFN-γ), released by T-cells. Herein a new electrochemical aptasensor was developed, where a methylene blue (MB)-tagged thiolated aptamer modified on a perovskite-based electrode platform was used to enable rapid and accurate detection of this biomarker. First, LiSmZrO 3 was used to modify the electrode surface to provide a stable platform for immobilization. Then, the MB-aptamer bioconjugate was introduced for efficient aptamer recognition of IFN-γ, which was bound to the electrode surface via Au-S interactions. When IFN-γ binds to the aptamer, it causes a conformational change, forming a detection basis. Differential pulse voltammetry and cyclic voltammetry were used to characterize the modifications to this sensing system and its response to different IFN-γ concentrations in buffered and human serum solutions. This aptasensor exhibited a linear peak current from 5 – 50 pg/mL IFN-γ, with a detection limit of 14.30 pg/mL. The aptasensor was specifically designed for IFN-γ, even in the presence of 10-fold interfering species. Moreover, the aptasensor was successfully used to analyze the presence of spiked IFN-γ in human serum, with a detection limit of 21.37 pg/mL. These results demonstrate the potential of this novel perovskite-based aptasensor as an efficient tool for diagnosing tuberculosis and other biomedical applications.