Sensitive sandwich-type voltammetric immunosensor for breast cancer biomarker HER2 detection based on gold nanoparticles decorated Cu-MOF and Cu2ZnSnS4 NPs/Pt/g-C3N4 composite

Abstract

A sandwich-type sensitive voltammetric immunosensor for breast cancer biomarker human epidermal growth factor receptor 2 (HER2) detection was prepared. The electrochemical immunosensor was developed based on gold nanoparticles decorated copper-organic framework (AuNPs/Cu-MOF) and quaternary chalcogenide with platinum-doped graphitic carbon nitride (g-C 3 N 4 ). Cu 2 ZnSnS 4 nanoparticle (CZTS NP) quaternary chalcogenide with platinum (Pt)-doped g-C 3 N 4 composite (Pt/g-C 3 N 4 ) was tagged as CZTS NPs/Pt/g-C 3 N 4 . AuNPs/Cu-MOF composite was successfully synthesized by amidation reaction between AuNPs functionalized with amino group and Cu-MOFs containing carboxylic acid. After the conjugations of primer HER2 antibody and antigen HER2 protein to AuNPs/Cu-MOF as sensor platform, CZTS NPs/Pt/g-C 3 N 4 composite was prepared by one-pot hydrothermal method. After immune reaction of 30 min, the prepared HER2 immunosensor was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD) method, x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The developed immunosensor showed high sensitivity with a detection limit of 3.00 fg mL −1 . Additional properties of the voltammetric immunosensor are high selectivity, stability, reproducibility, and reusability.

Sensitive sandwich-type electrochemical SARS-CoV‑2 nucleocapsid protein immunosensor

“…4A ). Electroactive surface areas of the prepared electrode surfaces were calculated as 0.173 ± 0.002 cm 2 for bare GCE, 0.319 ± 0.001 cm 2 for Bi 2 WO 6 /GCE, 0.647 ± 0.003 cm 2 for Bi 2 S 3 /GCE, and 1.113 ± 0.006 cm 2 for Bi 2 WO 6 /Bi 2 S 3 /GCE in the presence of 1.0 mM [Fe(CN) 6 ] 3− solution by i p = 2.69 × 10 5 A n 3/2 D 1/2 C v 1/2 , where i p was current, C (mol cm −3 ) was [Fe(CN) 6 ] 3− concentration, v was scan rate (10–500 mV s −1 ), and A was surface area (cm 2 ) ( n = 1, D = 7.6 × 10 –6 cm 2 s −1 for [Fe(CN) 6 ] 3− ) [ 67 ]. Thus, Bi 2 WO 6 /Bi 2 S 3 composite was chosen for future sensor platform.…”

“…Firstly, g-C 3 N 4 preparation was performed [ 43 ]. For this aim, the calcination of melamine (20.0 g) was conducted at 500 °C over 90 min.…”

Electrochemical immunosensor development based on core-shell high-crystalline graphitic carbon nitride@carbon dots and Cd0.5Zn0.5S/d-Ti3C2Tx MXene composite for heart-type fatty acid–binding protein detection

“…h-FABP free plasma samples were supplied from Blood Bank in TURKEY. Sample preparation protocol was explained in detail on Supplemantary Data [47].…”

“…Finally, due to significant catalysis effect of Cd 0.5 Zn 0.5 S [41] and important synergistic effect between Cd 0.5 Zn 0.5 S and 7wt%d-Ti 3 C 2 T x MXene, the higher current signals (curve d) on Cd 0.5 Zn 0.5 S/7wt%d-Ti 3 C 2 T x MXene/h-FABP-Ab 2 were found in comparison with 7wt%d-Ti 3 C 2 T x MXene/h-FABP-Ab 2 . In addition, the specific surface areas of developed immunosensors were calculated as 0.170 ± 0.04 cm 2 for bare GCE, 0.389 ± 0.03 cm 2 for h-FABP-Ab 2 /h-FABP/BSA/h-FABP-Ab 1 /hc-g-C 3 N 4 @CDs/GCE, 0.607 ± 0.01 cm 2 for 7wt%d-Ti 3 C 2 T x MXene/h-FABP-Ab 2 /h-FABP/BSA/h-FABP-Ab 1 /hc-g-C 3 N 4 @CDs/GCE, and 0.917 ± 0.03 cm 2 for Cd 0.5 Zn 0.5 S/7wt%d-Ti 3 C 2 T x MXene/h-FABP-Ab 2 /h-FABP/ BSA/h-FABP-Ab 1 /hc-g-C 3 N 4 @CDs/GCE in the presence of 1.0-mM [Fe(CN) 6 ] 3− solution by the equation (Randles-Sevcik) of i p = 2.69 × 10 5 A n 3/2 D 1/2 C v 1/2 , where i p was the current, C (mol cm −3 ) was [Fe(CN) 6 ] 3− concentration, v was the scan rate (10-500 mV s −1 ), and A was surface area (cm 2 ) (n = 1, D = 7.6 × 10 −6 cm 2 s −1 for [Fe(CN) 6 ] 3− ) [47]. Thus, Cd 0.5 Zn 0.5 S/7wt%d-Ti 3 C 2 T x MXene/h-FABP-Ab 2 was preferred for subsequent immunosensor applications.…”

Amorphous carbon nitride microband integrated in a microfluidic device for DNA biosensors applications

“…Additionally, carbon nitride based nanomaterials appears as promising new class for nanosensors. Among them, graphitic carbon nitride (g-C3N4) and ultra-thin graphitic carbon nitride (utg-C3N4) and their hybridized forms: tubular form (C3N4 NTs), metallic (Au, Pt) nanoparticle-functionalized nanosheets (g-C3N4@Au NPs), or dots composite (g-C3N4/NCDS) can drastically enhance electrochemical performances in photocatalysis or sensing applications [19][20][21][22][23].…”