Sandwich-Type Electrochemical Sensor for Mucin-1 Detection Based on a Cysteine–Histidine–Cu@Cuprous Oxide Nanozyme

Abstract

The sensitive detection of biomarkers is crucial for the early identification and treatment of cancer. In this study, a cysteine–histidine–Cu-modified jujube-like Cu2O (CH-Cu@J-Cu2O) nanozyme was synthesized and used to fabricate an electrochemical sensor for mucin-1 (MUC1) sensitive detection. Gold-modified reduced graphene oxide and CH-Cu@J-Cu2O for the sensor were prepared and also characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The CH-Cu@J-Cu2O nanozyme was used as a signal probe, containing two catalytic units of cysteine–histidine–Cu and jujube-like Cu2O. The CH-Cu@J-Cu2O nanozyme can potently catalyze the H2O2-driven oxidation of dopamine to aminochrome, leading to a high-level electrochemical signal. This electrochemical sensor was used to detect MUC1 with a linear range from 0.5 to 5000 pg·mL–1, and the limit of detection was 0.085 pg·mL–1, owing to the excellent catalytic activity of CH-Cu@J-Cu2O. The expression of MUC1 on the surface of MCF-7 cells was further analyzed, and the results indicate that the proposed strategy is practical for the detection of biomarkers.

Nanozyme‐Enhanced Electrochemical Biosensors: Mechanisms and Applications

“…[150] In a seminal endeavor, Wang et al have engineered a novel nanozyme designated as thiol-histidine-Cu-modified date-like Cu 2 O (CH-Cu@J-Cu 2 O), illuminating the path toward an electrochemical sensor finely attuned for the discernment of MUC1 with striking sensitivity. [151] The structure of the sensor ingeniously consists of a signaling probe, artfully weaving together the catalytic constituents thiolhistidine-Cu and date-like Cu 2 O, where the CH-Cu@J-Cu 2 O nanozyme unfurls its multifaceted persona as both a catalyst and a carrier. In this orchestration, the Cu 2 O element assumes the mantle of a catalytic linchpin in the dopamine oxidation process.…”

“…Against this backdrop, the innovation of a dual-modal PEC and EC sensing framework assumes paramount importance in the realm of urease detection. [151] Copyright 2022, American Chemical Society. b) Mechanism of dual-modal PEC and EC biosensor based on AuPtPd nanozymes and BiVO 4 for urease detection.…”

“…have engineered a novel nanozyme designated as thiol‐histidine‐Cu‐modified date‐like Cu 2 O (CH‐Cu@J‐Cu 2 O), illuminating the path toward an electrochemical sensor finely attuned for the discernment of MUC1 with striking sensitivity. [ 151 ]…”

“…a) Fabrication process of the sandwich-type electrochemical MUC1 sensor. Reproduced with permission [151]. Copyright 2022, American Chemical Society.…”

Ultrathin Cu–TCPP Nanosheet-Based Electrochemical Microsensor for Detecting the Immunosuppressive Drug Mycophenolic Acid

“…These methods generally require large-scale instruments, multiple treatment stages, and professionally trained staff and cannot guarantee the avoidance of cross-reactivity due to interfering substances. Electrochemical sensing technology can be used for target analysis because it has the advantages of good repeatability and accuracy, high sensitivity, convenience, and real-time detection. − Additionally, the integration, intelligence, and miniaturization of electrochemical sensors can be achieved by combining them with the micro-electromechanical system (MEMS) or printed electronics technology . Electrochemical microsensors can not only be used to detect biological macromolecules but also directly detect molecules with electrochemical activity based on the electrochemical catalytic principle. , With the advantages of miniaturization, rapid response, convenience, and portability, electrochemical microsensors would also have great application prospects for continuously monitoring immunosuppressive drugs …”