A nanostructured cerium oxide film-based immunosensor for mycotoxin detection

National Physical Laboratory, New Delhi 110012, India.
Nanotechnology (Impact Factor: 3.82). 03/2009; 20(5):055105. DOI: 10.1088/0957-4484/20/5/055105
Source: PubMed


Rabbit-immunoglobulin antibodies (r-IgGs) and bovine serum albumin (BSA) have been immobilized onto sol-gel-derived nanostructured cerium oxide (nanoCeO(2)) film fabricated onto an indium-tin-oxide (ITO) coated glass plate to detect ochratoxin-A (OTA). Broad reflection planes obtained in x-ray diffraction (XRD) patterns reveal the formation of CeO(2) nanostructures. Electrochemical studies reveal that nanoCeO(2) particles provide an increased electroactive surface area for loading of r-IgGs with desired orientation, resulting in enhanced electron communication between r-IgGs and electrode. BSA/r-IgGs/nano CeO(2)/ITO immunoelectrode exhibits improved characteristics such as linear range (0.5-6 ng dl(-1)), low detection limit (0.25 ng dl(-1)), fast response time (30 s) and high sensitivity (1.27 microA ng(-1) dl(-1) cm(-2)). The high value of the association constant (K(a), 0.9 x 10(11) l mol(-1)) indicates the high affinity of the BSA/r-IgGs/nanoCeO(2)/ITO immunoelectrode to OTA.

Download full-text


Available from: Ajeet Kaushik
    • "Citrinin (CIT) Horseradish Peroxidase (HRP) MWCNTs Amperometry e 63 pg mL À1 Rice [30] AFB 1 Anti-AFB 1 MAb GO Cyclic Voltammetry (CV) 0.125e1.5 ng mL À1 0.15 ng mL À1 e [32] OTA Anti-OTA PAb Au NPs DPV 0.3e8.5 ng mL À1 0.20 ng mL À1 Wheat [38] OTA Anti-OTA MAb Au NPs DPV 0.15e9.9 ng mL À1 0.10 ng mL À1 Wheat [39] OTA Anti-OTA aptamer IrO 2 NPs EIS 4 pg mL À1 e40 ng mL À1 5.65 pg mL À1 White wine [40] OTA IgG CeO 2 NPs DPV 2.5e60 pg mL À1 2.5 pg mL À1 e [41] [42] OTA IgG ZnO NPs EIS 2.5e4.2 pg mL À1 2.5 pg mL À1 e [43] OTA Anti-OTA MAb "
    [Show abstract] [Hide abstract]
    ABSTRACT: The use of nanotechnology in bioanalytical devices has special advantages in the detection of toxins of interest in food safety and environmental applications. The low levels to be detected and the small size of toxins justify the increasing number of publications dealing with electrochemical biosensors, due to their high sensitivity and design versatility. The incorporation of nanomaterials in their development has been exploited to further increase their sensitivity, providing simple and fast devices, with multiplexed capabilities. This paper gives an overview of the electrochemical biosensors that have incorporated carbon and metal nanomaterials in their configurations for the detection of toxins. Biosensing systems based on magnetic beads or integrated into microfluidics systems have also been considered because of their contribution to the development of compact analytical devices. The roles of these materials, the methods used for their incorporation in the biosensor configurations as well as the advantages they provide to the analyses are summarised.
    No preview · Article · Dec 2015 · Analytica chimica acta
  • Source
    • "Advancement in biosensing technique in various fields has led to increased attention towards biosensors (Chauhan, Nagar, Solanki, & Basu, 2013; Pandey, Singh, Sumana, Pandey, & Malhotra, 2011), wherein recognition of specific toxins by the corresponding antibody offers advancement for rapid, reliable and sensitive detection of mycotoxins in food products. Currently, the immunosensors for the AFB1 detection include electrochemical (Kaushik, Solanki, Ansari, Ahmad, & Malhotra, 2009), optical waveguide light mode spectroscopy , micro cantilever (Adyani et al. 2007; Riccardi et al. 2013), surface plasmon resonance (Park, Kim, Kim, & Ko, 2014; Puiu, Istrate, Rotariu, & Bala, 2012), fluorescent (Carlson et al. 2000; Prieto-Sim on, Karube, & Saiki, 2012), and quartz crystal (piezoelectric) microbalance (Liao, 2007; Wang & Gan, 2009). "
    [Show abstract] [Hide abstract]
    ABSTRACT: An electrochemical quartz crystal microbalance (EQCM) based label-free immunosensor has been developed for the quantitative detection of aflatoxin B1 (AFB1) in groundnut. The gold (Au) coated quartz crystal (6 MHz) functionalized with self-assembled monolayer (SAM) of 4-aminothiophenol (4-ATP) has been utilized to immobilize anti-aflatoxin antibodies (aAFB1). The quartz crystal microbalance QCM frequency and EQCM cyclic voltammetry measurements have been used to optimize the deposition of SAM layer on Au electrode (4-ATP/Au), antibody immobilization (aAFB1/4-ATP/Au), bovin serum albumin (BSA) adsorption (BSA/aAFB1/4-ATP/Au) and immuno interaction (AFB1/BSA/aAFB1/4-ATP/Au). Interestingly, the EQCM studies conducted on this immunoelectrode provide wider linear range of 0.1–4.0 ng mL−1 and higher sensitivity than those obtained using under identical condition. The high association constant of 9.4 × 10−2 ng mL−1 of the EQCM immunosensor can be attributed to molecularly oriented self assembled monolayer of 4-ATP on QCM gold electrode that acts as a nanowire between aAFB1 and electrode through amide linkage formed by the NH2 group of 4-ATP and COOH group of Fc part of aAFB1. This linkage also helps to project paratope part of aAFB1 to interact with AFB1. The developed label free EQCM based immunosensor was tested for the AFB1 detection in the extract of contaminated groundnut and the results were compared with Liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. The comparative results demonstrate the suitability of this sensor for routine screening of groundnut and the percent error is found to be ±12%.
    Full-text · Article · Jun 2015 · Food Control
  • Source
    • "Ansari et al. utilized Nano-ZnO film deposited on an indium-tin-oxide (ITO) with immobilized rabbit-immunoglobulin and bovine serum albumin to reach a detection limit of 0.006 nM/dm of the toxin. Similarly, Kaushik et al. used nanostructured cerium oxide to achieve a detection limit of 0.25ng/dL of ochratoxin (Kaushik et al., 2009a "
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract The post-genomics era has brought about new Omics biotechnologies, such as proteomics and metabolomics, as well as their novel applications to personal genomics and the quantified self. These advances are now also catalyzing other and newer post-genomics innovations, leading to convergences between Omics and nanotechnology. In this work, we systematically contextualize and exemplify an emerging strand of post-genomics life sciences, namely, nanoproteomics and its applications in health and integrative biological systems. Nanotechnology has been utilized as a complementary component to revolutionize proteomics through different kinds of nanotechnology applications, including nanoporous structures, functionalized nanoparticles, quantum dots, and polymeric nanostructures. Those applications, though still in their infancy, have led to several highly sensitive diagnostics and new methods of drug delivery and targeted therapy for clinical use. The present article differs from previous analyses of nanoproteomics in that it offers an in-depth and comparative evaluation of the attendant biotechnology portfolio and their applications as seen through the lens of post-genomics life sciences and biomedicine. These include: (1) immunosensors for inflammatory, pathogenic, and autoimmune markers for infectious and autoimmune diseases, (2) amplified immunoassays for detection of cancer biomarkers, and (3) methods for targeted therapy and automatically adjusted drug delivery such as in experimental stroke and brain injury studies. As nanoproteomics becomes available both to the clinician at the bedside and the citizens who are increasingly interested in access to novel post-genomics diagnostics through initiatives such as the quantified self, we anticipate further breakthroughs in personalized and targeted medicine.
    Full-text · Article · Jan 2014 · Omics: a journal of integrative biology
Show more