Optimization of Mxene/Pedot:Pss Nanocomposite for Label-Free Aptasensing of Zearalenone Publisher



Eshtiaghi M¹ ; Pishbin F¹ ; Hassani S^{2, 3} ; Ramezanzadeh B⁴ Show Affiliations
Source: Colloids and Surfaces A: Physicochemical and Engineering Aspects Published:2025

Abstract

The implementation of nanomaterials into biosensing platforms offers an innovative solution to sensing challenges in complex systems. This study presents an ultrasensitive electrochemical aptasensor for detecting zearalenone (ZEN), utilizing MXene/PEDOT:PSS nanocomposite (NC). Successful synthesis of the MXene 2D structure is confirmed through XRD, Raman spectroscopy, and FE-SEM results. To optimize sensing performance, the component ratios in the nanocomposite are fine-tuned using EIS and CV measurements. The optimal specimen is selected based on its minimal charge transfer resistance (1.06 × 101 Ω.cm2) and maximum signal output (110.4 μA). The evaluation of chemical bonding and terminal groups in the MXene and PEDOT:PSS components of the NC via FTIR and XPS analyses, along with TEM micrographs, confirming successful fabrication of the multi-layered composite. Following aptamer (APT) loading onto the NC, DPV analyses show that the APT/NC platform successfully detects ZEN over a concentration range of 1 pg/mL to 100 ng/mL, with a LOD of 0.028 pg/mL. Moreover, the aptalyzer selectively detects ZEN in the presence of ochratoxin A (OTA), patulin (PAT), and aflatoxin B1 (AFB1). Evaluations of other critical biosensing aspects, including stability, repeatability, and reproducibility, demonstrate promising sensor performance. Ultimately, accurate and precise measurements of ZEN in spiked maize samples underscore the potential for future applications of this platform in complex media. © 2025 Elsevier B.V.