Electrochemical Cytosensor Based on a Gold Nanostar-Decorated Graphene Oxide Platform for Gastric Cancer Cell Detection

Abstract

Effectively capturing and sensitively detecting cancer cells are critical to clinical diagnosis and cancer therapy. In this work, we prepared gold nanostar-decorated graphene oxide (GO-AuNSs) nanocomposites using a ultraviolet (UV)-induced strategy, and then modified them with a layer of bio-complex rBSA-FA (coupled reduced bovine serum albumin with folic acid) to generate GO-AuNSs@rBSA-FA nanocomposites. Herein, the application of GO and AuNSs not only strengthened the conductivity of the sensing platform but also guaranteed nanocomposites with biocompatible performance. Moreover, the adopted rBSA-FA layer could effectively enhance the stability and specificity towards gastric cancer cells (MGC-803). According to a systemic construction procedure, a novel electrochemical cytosensor based on GO-AuNSs@rBSA-FA was fabricated for MGC-803 cell detection. With the assistance of cyclic voltammetry (CV) and differential pulse voltammetry (DPV), the cytosensor reached a detection limit of 100 cell/mL in a wide linear range of 3 × 102~7 × 106 cell/mL towards MGC-803 cells. The good electrochemical characteristics for the cancer cell analysis indicate a promising prospect of this electrochemical cytosensor in clinical cancer diagnosis.

Electrochemical interface based on polydopamine and gold nanoparticles/reduced graphene oxide for impedimetric detection of lung cancer cells

“…This value is comparable with those obtained in previous works (Table S2†). 23,26,43–45 Indeed, PDA has been reported to be a suitable material to develop electrochemical cytosensor for detection of A-549 due to the strong adhesion between PDA and receptor-rich tumor cells. 23 Also, the detection limit was improved by fourteen times compared with sensing platform without AuNPs/rGO ad-layer (Fig S5†).…”

“…Despite of the good adhesive property, 24 the low conductivity and slow electron transfer at PDA layer might still somehow affect to the recorded signals. Thus, some more conductive nanostructures with good biocompatibility such as gold nanoparticles and carbonaceous materials 25,26 should be employed. In this work, we aim to develop an impedimetric cytosensor based on polydopamine in combination with gold nanoparticles (AuNPs) and reduced graphene oxide (rGO).…”

Electrochemical Biosensor Based on l-Arginine and rGO-AuNSs Deposited on the Electrode Combined with DNA Probes for Ultrasensitive Detection of the Gastric Cancer-Related PIK3CA Gene of ctDNA

“…The electrochemical detection of the PIK3CA gene in ctDNA samples was done according to our previous reports. − Briefly, 2 mM ferri-ferrocyanide in 0.1 M KCl was used for performing the EIS measurements. The EIS AC voltage amplitude was set at 5 mV with a 10 000 to 0.1 Hz frequency range.…”

“…The proposed sensor combines the advantages of the polymeric film formation of an l -arginine monomer and a AuNS-rGO-modified GC electrode (GCE/P-arg/rGO-AuNS), and the DNA probes capturing the PIK3CA gene were immobilized directly on the electrode by Van der Waals interaction. The immobilization of the DNA probes was done with a very simple and fast method using a well-known carbodiimide reaction, which formed a covalent bond and enhanced the immobilization performance on the P-arg/rGO-AuNS-modified GCE surface. The resultant electrochemical sensor was applied to detect the PIK3CA gene of ctDNA in the peripheral blood, exhibited high sensitivity and specificity, and has great potential for application in the detection of gene biomarkers of ctDNA for tumor diagnosis.…”

“…The incorporation of AuNSs into graphene oxide on the poly­( l -arg) bedded surface effectively prevents the agglomeration and restacking of the rGO nanosurface by a process of reduction and helps to achieve the target specificity and sensitivity of the biosensor . In our previous works, we developed a gold nanoparticle-decorated graphene oxide platform for gastric cancer cell detection, electrochemical detection of circulating tumor DNA, salivary SERS sensing, and breath analysis to distinguish early and advanced gastric cancer patients from healthy persons …”