Colorimetric Aptasensor for Sensitive Glypican-3 Detection based on Hemin-reduced oxide graphene-platinum@palladium Nanoparticles with Peroxidase-like Activity

• Published in: IEEE sensors journal Vol. 23; no. 1; p. 1
• Main Authors: Li, Guiyin, Li, Haimei, Wang, Chaoxian, Li, Xinhao, Chen, Jiejing, Liang, Jintao, Zhou, Zhide
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antibodies; Biomarkers; colorimetric aptasensor; Colorimetry; Free radicals; Glypican-3; Graphene; Hydrogen peroxide; Hydroxyl radicals; Liver cancer; Nanoparticles; nanozymes; Palladium; Peroxidase; peroxidase-like activity; Platinum; Sandwich structures; Selectivity
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2022.3224554

In recent years, nanozymes-based sensing platforms have been attracted for their excellent performances in practical applications. Glypican-3 (GPC3) has been extensively regarded as a sensitive biomarker for hepatocellular carcinoma (HCC). In this work, the Hemin-reduced oxide graphene-platinum@palladium NPs (H-R-Pt@Pd NPs) with the peroxidase-like activity has been used to construct a facile colorimetric aptasensor for GPC3 detection. GPC3 aptamer (Apt) conjugated to the surface of H-R-Pt@Pd NPs serves as a signal probe, and GPC3 antibody (Ab) uses as a capture probe. In the presence of GPC3, it was recognized by the Ab and the Apt on the H-R-Pt@Pd NPs and initiated the formation of an H-R-Pt@Pd NPs-Apt/GPC3/Ab sandwich structure complex. Taking advantage of the excellent enzymatic catalytic properties, H-R-Pt@Pd NPs can oxidase colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue oxTMB with the presence of H 2 O 2 , the absorbance of the system at 652 nm changed consequently, which realize the sensitive colorimetric detection of GPC3. In addition, the catalytic mechanism of H-R-Pt@Pd NPs was confirmed by free radical experiments to be induced by hydroxyl radicals (∙OH). Under optimal conditions, the aptasensor has a linear range of 10.0 to 300.0 ng/mL, and a limit of detection (LOD) of 5.06 ng/mL. Furthermore, the aptasensor is employed to detect GPC3 in human serum samples with the recoveries of 105.94%-116.33% and RSDs of 0.93%-3.08%. Overall, this assay possesses high selectivity and operability, and good sensitivity, indicating the potential for GPC3 detection in the field of clinical HCC diagnosis.