Nanocellulose-modified electrodes for simultaneous biosensing of microbiome-related oral diseases biomarkers.

The preparation of a dual immunosensor for the simultaneous determination of two important microbiome-related oral disease biomarker matrix metalloproteinases MMP-9 and MMP-13 is reported. Screen-printed dual carbon electrodes (SPdCEs) modified with reduced graphene oxide and crystalline nanocellulose (rGO/CNC) were used for the immobilization of specific capture antibodies and the implementation of sandwich-type immunoassays using biotinylated secondary antibodies. Amperometric detection through the hydroquinone HQ/HO system was employed.

Electrochemical immunosensing of Crohn's disease biomarkers using diazonium salt-grafted crystalline nanocellulose/carbon nanotube-modified electrodes.

The first dual immunosensor is reported for the determination of IL-12 and IL-23, two relevant biomarkers of Crohn's disease (CD). The strategy relies on the selective capture of the targets by the respective antibodies which were covalently immobilized onto SPCEs modified with crystalline nanocellulose (CNC) and multi-walled carbon nanotubes (MWCNTs) followed by conjugation with a detector antibody labelled with poly-HRP-Strept and amperometric transduction using the HO/HQ system. The combination of CNC, a nanomaterial scarcely exploited in immunosensing, with MWCNTs enables the preparation of a novel dual immunosensor for the determination of CD biomarkers in clinical samples, including faeces.

Electrochemical immunoplatform for the determination of multiple salivary biomarkers of oral diseases related to microbiome dysbiosis.

Several diseases of the oral cavity are related to compositional and functional shifts in the oral microbiome. The analysis of saliva is an attractive alternative for the diagnosis and prognosis of these diseases. Samples can be obtained by no invasive procedures and processing is relatively simple.

Label-free electrochemical immunosensing of glial fibrillary acidic protein (GFAP) at synthesized rGO/MoS/AgNPs nanocomposite. Application to the determination in human cerebrospinal fluid.

An electrochemical bioplatform involving screen-printed carbon electrodes modified with rGO/MoS/AgNPs nanocomposites, the covalent immobilization of the specific capture antibody, and label-free detection has been developed for the determination of Glial Fibrillary Acidic Protein (GFAP). The resulting immunosensor profits the benefits of the rGO high conductivity, the pseudo-peroxidase activity of MoS and the electrocatalytic effect provided by AgNPs for improving the reduction current responses of hydrogen peroxide at the electrode surface. GFAP is a biomarker of central nervous system injuries has been proposed for the detection and monitoring of neurological diseases as epilepsy, encephalitis, or multiple sclerosis.

Carbon-Based Enzyme Mimetics for Electrochemical Biosensing.

Natural enzymes are used as special reagents for the preparation of electrochemical (bio)sensors due to their ability to catalyze processes, improving the selectivity of detection. However, some drawbacks, such as denaturation in harsh experimental conditions and their rapid de- gradation, as well as the high cost and difficulties in recycling them, restrict their practical applications. Nowadays, the use of artificial enzymes, mostly based on nanomaterials, mimicking the functions of natural products, has been growing.