Lipid–Lipid Interactions in Aminated Reduced Graphene Oxide Interface for Biosensing Application

Abstract

A label-free biosensor based on antiapolipoprotein B 100 functionalized-aminated reduced graphene oxide interface has been fabricated for detection of low density lipoprotein (LDL or lipid) cholesterol. The aminated reduced graphene oxide (NH2-rGO) based electrode surface is covalently functionalized with antiapolipoprotein B 100 (AAB or lipid) using EDC/NHS coupling chemistry. The lipid-lipid interactions at the NH2-rGO electrode surface have been investigated using electrochemical impedance spectroscopic technique. The structural and morphological investigations of NH2-rGO based immunosensor have been accomplished via transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV-visible, and electrochemical techniques. The impedimetric response of the proposed immunosensor shows excellent sensitivity (612 Ω mg(-1) dL cm(-2)), a response time of 250 s, and a low detection limit of 5 mg/dL of LDL molecules. The association, dissociation, and equilibrium rate constants for this immunoelectrode are found to be 1.66 M(-1) s(-1), 0.6 s(-1), and 2.77 M(-1), respectively. The long-term stability and excellent reproducibility of the proposed immunosensor indicates a suitable platform for detection of LDL or lipid molecules. This immunosensor provides an efficient platform for analysis of the antigen-antibody interactions of lipid molecules.

A SERS microfluidic platform for targeting multiple soluble immune checkpoints

“…The GO functionalized device was then bonded to the PDMS containing the channels and the device was sandwiched between custom-built holders and fixed into a microfluidic platform. This step was then followed by HA antibody functionalization in separate channels of the device using standard EDC-NHS chemistry (EDC: 0.2 M; NHS: 0.05 M; mixing volume ratio of 1: 1) (Ali et al 2014). NY-scFv specific anti-PD-1 affinity agents (10 μg/mL) was immobilized with the use of a human influenza hemagglutinin (HA) antigen tag cloned into the recombinant scFv construct at room temperature for 1h leading to the immobilization of the antibody onto the GO functionalized gold surface.…”

Strong hydrophobic interaction between graphene oxide and supported lipid bilayers revealed by AFM

“…Graphene‐related nanomaterials are believed to have great potential in applications in the fields of biology and biomedicine (Liu et al, , ; Sanchez et al, ; Sun et al, ; Wang et al, ; Yi and Gao, ), and have been used for biosensors (Ali et al, ; Ang et al, ; Liu et al, ; Qing et al, ), antibacterials (Dallavalle et al, ; Duan et al, ; Li et al, ; Mao et al, ; Pham et al, ; Pykal et al, ; Tu et al, ), bioimaging (Qian et al, ; Shi et al, ; Sun et al, ; Wang et al, ), regulation of cell growth and differentiation (Lee et al, ; Ruiz et al, ). Recently, the interaction between graphene oxide (GO) and cell membranes, including supported lipid bilayers (SLBs), has become the focus of many researchers (Frost et al, ; Furukawa and Hibino, ; Lei et al, ; Li et al, a,b; Okamoto et al, ; Phan et al, ; Rui et al, ; Wu et al, ) not only because cell membrane is the first barrier when GO interacts with intracellular components, but also it can provide us valuable information on physicochemical nature of GO.…”

Carbon Nanomaterials‐based Electrochemical Immunoassay with β‐Galactosidase as Labels for Carcinoembryonic Antigen

“…The GO‐NH 2 were prepared by using the reported method with some modifications and the process was shown in Scheme A. Typically, 10 mg of GO was dispersed into 100 mL of SOCl 2 under ultrasonication for 40 min.…”