A Label-Free Electrochemical Immunosensor for Detection of the Tumor Marker CA242 Based on Reduced Graphene Oxide-Gold-Palladium Nanocomposite

Abstract

As a tumor marker, carbohydrate antigen 24-2 (CA242) is a highly accurate and specific diagnostic indicator for monitoring pancreatic and colorectal cancers. The goal of this study was to create a novel label-free electrochemical immunosensor using a nanocomposite glassy carbon electrode for the detection of CA242. Graphene oxide (GO) and polyvinyl pyrrolidone were chosen as the dopants for the preparation of a high-performance reduced-GO-gold-palladium (rGO-Au-Pd) nanocomposite. RGO-Au-Pd was characterized using X-ray diffraction and transmission electron microscopy, revealing that the material exhibited superior electrochemical redox activity and electron transfer ability. The effects of the synthesis method, material concentration, reduction cycle, and pH were investigated to optimize the performance of the immunosensor. As a result of the catalytic activity and biocompatibility of rGO-Au-Pd, the prepared CA242 immunosensor displayed a wide linear range of detection from 0.001 U/mL to 10,000 U/mL with a detection limit of 1.54 × 10−3 U/mL and a sensitivity of 4.24 μA (log10CCA242)−1. More importantly, the immunosensor exhibited satisfactory reproducibility and selectivity when detected CA242 in PBS or human serum. The results of our study provide a platform for the development of novel bioassays for use in early cancer diagnosis and promote the application of biosensing technology in the medical field.

Comprehensive Analysis of Immunoinhibitors Identifies LGALS9 and TGFBR1 as Potential Prognostic Biomarkers for Pancreatic Cancer

“…To improve early detection and prognosis and to provide timely and effective treatment for high-risk patients, predictive biomarkers for PC are required [ 3 , 4 ]. To date, carbohydrate antigen 199 (CA199) and CA242, which are currently used in clinical settings as serum biomarkers for PC, are inadequate for early screening and prognosis [ 5 , 6 ]. To uncover the unknown novel biomarker used to indicate early diagnosis and prognosis in the molecular therapeutic field of PC is extremely of importance.…”

A novel electrochemical immunosensor based on PdAgPt/MoS2 for the ultrasensitive detection of CA 242

“…The sensitivity of the electrochemical immunosensor is affected by the catalytic activity of the electrode surface, so the catalytic performance of nanomaterials is a key factor affecting the performance of the immunosensor. According to the references (Van Venrooij and Koper, 1995;Felix and Angnes, 2018;Wu et al, 2019), Amperometric i-t technique is used to detect antigen content through different current signals generated on the electrode surface. The reduction reaction of hydrogen peroxide occurs under the catalysis of the substrate material, and the current generated on the electrode surface is proportional to the concentration of antigen.…”

“…Preoperative detection of CA242 combined with other tumor markers can improve prognostic prediction of patients undergoing colorectal cancer surgery ( Kuang et al, 2020 ; Luo et al, 2020 ). However, there are few studies on CA242 detection methods ( Tang et al, 2017 ; Du et al, 2019 ; Shen et al, 2022 ), so it is very important to develop sensitive and accurate detection methods for CA242.…”

Nanostructure-Based Electrochemical Immunosensors as Diagnostic Tools

“…Different applications also concern the use of multimetallic nanocomposites that involve high catalytic ability and large surface/volume ratio. An example is the one reported by Xi Du et al concerning a label-free electrochemical immunosensor for detection of the tumor marker CA242 (cut-off 20 U/mL [107]) investigated in pancreatic and colorectal cancers [108], the first one based on the redox-active rGO-Au-Pd nanocomposite. This immunosensor exhibits a linear range of 0.001-10,000 U/mL with a LOD of 1.54 × 10 −3 U/mL and it could be used in early diagnosis.…”