This work concentrates on the design and implementation of aptamer-based electrochemical biosensors using a layer-by-layer approach for precise tracking of mucin-1 (MUC1), an important biomarker linked to breast cancer. The electrochemical biosensor was created by modifying a screen-printed carbon electrode (SPCE) with V2C MXene booster and gold nanoparticles (Au-NPs), along with Cd2+ integrated aptamer (AP) (SPCE/V2C-MXene/Au NPs/Cd2+-AP). This biosensor demonstrated high specificity and affinity for MUC1, establishing a sensitive quantification mechanism. The MXene nanolayer was produced and analyzed via TEM, XPS, SEM, AFM, BET, and MAP techniques. It served as a supportive material that enhanced electrochemical conductivity and allowed for the integration of the aptamer (AP) as the biological recognition component. The biosensor was constructed by immobilizing MUC1-specific aptamers onto the surfaces of SPCE/V2C-MXene/Au NPs, enabling selective recognition and binding with MUC1. The recorded signal, corresponding to Cd2+ integrated with AP at SPCE/V2C-MXene/Au NPs/Cd2+-AP, enabled quantitative assessment of MUC1 levels. The findings showed a linear concentration span of 1.0–500 pg/mL for detecting MUC1, achieving a detection limit of 3.45 fg/mL utilizing the SPCE/ V2C-MXene/Au NPs/Cd2+-AP biosensor. The SPCE/V2C-MXene/Au NPs/Cd2+-AP biosensor exhibited a good affinity for the detection of MUC1 in the presence of other breast cancer biomarkers, confirming its selectivity.

Enhancing cancer biomarker identification: precise monitoring of MUC1 using V2CAu nanocomposite-amplified electrochemical biosensor
    Abstract
    1 Introduction
    2 Experimental part
        2.1 Components and reactants
        2.2 V2C-MXene synthesis
        2.3 Biosensor preparation and fabrication protocol
    3 Results and discussions
        3.1 Analysis of MXene catalyst
        3.2 Electrochemistry of work
            3.2.1 Biosensor modification investigation
            3.2.2 Role of effective factors in biosensor application
        3.3 Analytical performance evaluation of the biosensor
    4 Conclusions
    References

• Najmeh Zare(School of Resources and Environment, University of Electronic Science and Technology of China, Xiyuan Ave, Chengdu 611731, China)
• Hassan Karimi‑Maleh(The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou 324000, China)
• Zhouxiang Zhang(Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, China)
• Li Fu(College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, People’s Republic of China)
• Jalal Rouhi(Department of Physics, University of Tabriz, Tabriz, Iran)
• Nianbing Zhong(Chongqing Engineering Research Center of Intelligent Optical Fiber Sensing Technology, Chongqing University of Technology, Chongqing 400054, China)
• Yangping Wen(Institute of Functional Materials and Agricultural Applied Chemistry, Jiangxi Agricultural University, Nanchang 330045, China)
• Masoumeh Ghalkhani(Electrochemical Sensors Research Laboratory, Department of Chemistry, Faculty of Science, Shahid Rajaee Teacher Training University, Lavizan, Tehran, Iran)