Ultrasensitive interferon-gamma sensor with a bifunctionalized conducting polymer nanobioconjugate for therapy-progress monitoring of cancer patients

• Published in: Sensors and actuators. B, Chemical Chemical, 2024-01, Vol.398, p.134739, Article 134739
• Main Authors: Saputra, Heru Agung, Chung, Jae Heun, Kwon, Ryuk Jun, Jannath, Khatun A., Park, Deog-Su, Shim, Yoon-Bo
• Format: Article
• Language: English
• Subjects: Aptamer; Bifunctional conducting polymer; Cancer immunotherapy; Ferrocene; Interferon-gamma; Nanobioconjugate
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2023.134739

An ultrasensitive electrochemical aptasensor was designed with a bifunctionalized conducting polymer nanobioconjugate to monitor patients’ progress in cancer immunotherapy by detecting IFN-γ. The sensing probe was fabricated by covalently immobilizing aptamer on a polyterthiophene benzoic acid composited with multi-walled carbon nanotube/Au nanoparticles. The nanobioconjugate was prepared through the self-assembly of bifunctionalized terthiophene aminobenzoic acid (TABA) onto AuNPs then covalently attached with a redox indicator and an antibody on the amine and carboxyl groups of TABA, respectively. At the optimized condition, the sensor detected IFN-γ in the concentration range of 0.5 fM-100 pM with a detection limit of 0.46 ± 0.006 fM (RSD ≤5.1%). The sensor was applied to monitor the extracellular release of IFN-γ by peripheral blood mononuclear cells and the IFN-γ levels in patients’ serum before and after immunotherapy. We observed a low concentration of 0.07 ± 0.004 pM (RSD ≤5.6%) before therapy, which increased significantly to 0.43 ± 0.02 pM (RSD ≤5.1%) after immunotherapy. Meanwhile, a high IFN-γ level of 0.67 ± 0.04 pM (RSD ≤6.2%) was detected in healthy controls. In addition, our study showed IFN-γ is a more effective biomarker for predicting patients’ response to blockade therapy as compared to granzyme B. [Display omitted] •An ultrasensitive electroaptasensor was developed for interferon-gamma detection.•The probe was fabricated using the MWCNT-composited polyterthiophene on an Au nanoparticle layer.•The nanobioconjugate was synthesized with a bifunctionalized conducting polymer self-assembled on Au nanoparticles.•The cancer progressions before and after targeted immunotherapy were monitored using the proposed method.•Interferon-gamma is an effective biomarker for predicting patients’ response to blockade therapy.