Ultrasensitive All-Carbon Photoelectrochemical Bioprobes for Zeptomole Immunosensing of Tumor Markers by an Inexpensive Visible Laser Light

Abstract

A novel enzyme-free and all-carbon photoelectrochemical (PEC) bioprobe, based on carboxylated multiwalled carbon nanotube-Congo red-fullerene nanohybrids (MWNTCOOH-CR-C60), for the ultrasensitive immunosensing of carcinoembryonic antigen (CEA) was reported. The MWNTCOOH-CR-C60 nanohybrids, prepared by mechanically grinding a mixture of MWNTCOOH, C60, and CR at a certain mass ratio, had good water dispersibility and high PEC conversion efficiency in visible light ranges. Covalent binding of the detection antibody of CEA on the MWNTCOOH-CR-C60 nanohybrids produced a sensitive PEC bioprobe for detection of CEA by sandwich immunosensing. The corresponding immunosensor, employing an inexpensive and portable green laser light, possessed a wide calibration range of 1.0 pg/mL~100.0 ng/mL and a low detection limit of 0.1 pg/mL (calculated 5 zmol for a 10.0 μL sample solution) (S/N = 3), which was successfully applied to the detection of CEA in serum samples from both healthy people and cancer patients. The present work thus demonstrated the promising application of fullerene-based nanocomposites in developing highly sensitive, environmentally friendly, and cost-effective PEC biosensors.

Plasmonic AuNP/g-C3N4 Nanohybrid-based Photoelectrochemical Sensing Platform for Ultrasensitive Monitoring of Polynucleotide Kinase Activity Accompanying DNAzyme-Catalyzed Precipitation Amplification

“…Unfavorably, the potentially practical application of metallic semiconductors in the PEC sensors is still restricted, e.g., some semiconductors with the wide band-gap (e.g., 3.2 eV for TiO 2 ) are of strong oxidizing properties and require for high-energy excitation light sources (e.g., UV light) or suffer from photo-corrosion under illumination, thus easily resulting in fatal damage toward biomolecules or the instability of the sensors. [11][12][13] Despites some advances in this field, the quest for new PEC sensing platforms continues as both the clinical diagnostic and life science research communities constantly look from assay technologies that are sensitive, robust and easy to implement.…”

A versatile immobilization-free photoelectrochemical biosensor for ultrasensitive detection of cancer biomarker based on enzyme-free cascaded quadratic amplification strategy

“…To date, many approaches have been successfully developed for pursuing the exploration of extreme detection sensitivity toward cancer biomarkers (Chikkaveeraiah et al, 2012;Ding et al, 2015;Wu et al, 2007). Among these approaches, photoelectrochemical (PEC) biosensor is a newly emerged approach for the rapid and sensitive detection of cancer biomarkers (Fan et al, 2014;Hu et al, 2013;Li et al, 2013Li et al, , 2015Wang et al, 2009;Zeng et al, 2014aZeng et al, , 2014bZhang et al, 2014;Zhao et al, 2012a) and has drawn more and more concerns (Yang et al, 2015a(Yang et al, , 2015bZhao et al, 2014). Coupling photo-excitation with a current readout, PEC biosensors have inherited the advantages from both optical and electrochemical methods Ma et al, 2015) and offered a promising analytical platform for cancer biomarkers detection with greatly reduced background signals and strikingly improved sensitivity.…”

Novel Electrochemical Immunoassay for Carcinoembryonic Antigen Using Ferrocenyl Polymer Nanospheres

“…Immunoassays, based on antigen-antibody specific reactions, have been developed due to their specificity, sensitivity, and precision. These methods include fluorescence (Tian et al 2012), surface plasmon resonance (Pal, Rashid, and Bisht 2015), electrochemiluminescence (Feng et al 2015), and photoelectrochemical techniques (Hu et al 2013). Electrochemical immunosensors (Shen et al 2015;Zhang et al 2016) offer advantages of low-cost and light weight analysis.…”