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Nanotechnology: A Valuable Asset for Contribution to Positive Impact on Environment
Published in Ram Naresh Bharagava, Sandhya Mishra, Ganesh Dattatraya Saratale, Rijuta Ganesh Saratale, Luiz Fernando Romanholo Ferreira, Bioremediation, 2022
Ved Prakash Giri, Shipra Pandey, Madhuree Kumari, Aradhana Mishra
To detect pathogens at an early stage and at low cost has always been a mammoth task in medical research. Nanosensors because of their high catalytic property provide a low-cost and more accurate alternative to the current techniques available for sensing the pathogen and other chemicals. Glucose nanosensors have been used for the detection of increased glucose level, and triglyceride nanosensors are able to detect increased level of fat (Ansary and Faddah 2010). A nanoparticle hybridization assay has been developed, which involves ubiquitous and specific magnetic DNA probes targeting bacterial 16S rRNAs, to detect amplified target DNAs using a miniaturized NMR device (Chung et al. 2013). Kim et al. (2017) evaluated the potential of metal nanoparticles as the catalysts to establish high-performance sensor arrays for the pattern recognition of biomarkers to monitor their ability as chemosensitive biosensors. Banerjee et al. (2017) emphasized the importance of sensing and detecting pathogenic bacteria before the food reaches our dining table.
Nanosensors for Societal Benefits
Published in Vinod Kumar Khanna, Nanosensors, 2021
V. cholerae detection is done electrochemically, according to the procedure described in Figure 10.20 by differential pulse anodic stripping voltammetry (DPASV) in acidic medium (HBr/Br2) (Sheng et al. 2015). The procedure is subdivided into Parts A and B. For Part A, gold nanoparticles (AuNP)-polystyrene-co-acrylic acid (PSA)-avidin in lyophilized form are rehydrated and functionalized with the reporter probe to obtain the conjugate: AuNP-PSA-avidin-reporter probe. For the sandwich hybridization assay, the target DNA (PCR products amplified from genomic DNA (gDNA) of V. cholerae) is hybridized with the above conjugate, completing Part A. SPE preparation for AuNP/PSA genosensor (Sheng et al. 2015).
Surface engineering with Chemically Modified Graphene
Published in Craig E. Banks, Dale A. C. Brownson, 2D MATERIALS, 2018
Paul Sheehan, D. R. Boris, Pratibha Dev, S. C. Hernandez, Woo-Kyung Lee, Shawn Mulvaney, T. L. Reinecke, J. T. Robinson, Stanislav Tsoi, S. G. Walton, Keith Whitener
The first step in attaching biomolecules to GO begins by reacting ethylenediamine with the epoxy groups present on the GO surface. Amines will react spontaneously to relieve the epoxide ring strain, thereby covalently coupling an amine to the GO. From that point forward commercial products may be used, such as the two halves of the hydrazone reaction122, 163 to place neutravidin on the surface. Figure 10 shows the use of this chemistry to successfully produce both immunoassays and nucleic acid hybridization assays on a diverse set of substrates. Importantly, the assay for RCA atop silicon nitride was performed in beagle serum demonstrating compatibility with real world matrices. The slightly higher background signal due to matrix effects, ~ 10%, was expected and was consistent with previously published FFD assay results atop a glass slide using conventional surface passivation chemistries.161, 162 Finally, a graphene veil was successfully added to a flexible plastic substrate, polystyrene. For this experiment we demonstrated a different functionalization pathway. Neutravidin was covalently linked to the graphene veil through the native carboxyl groups using a carbodiimide crosslinker and a DNA hybridization assay was achieved. While this set of experiments is only a first demonstration, the work towards a universal surface chemistry marks one of the most promising uses of biofunctionalized graphene.
Pesticide exposure and genotoxic effects as measured by DNA damage and human monitoring biomarkers
Published in International Journal of Environmental Health Research, 2021
Jones A. Kapeleka, Elingarami Sauli, Patrick A. Ndakidemi
Different methods had been developed overtime in the analysis of pesticides biomarkers and genotoxicity of pesticides exposure. Biological monitoring had been applied to precisely evaluate human exposure to certain chemical substances because it determines the dose absorbed rather than the potential risk of exposure (Aprea 2012). Of recent, the most widely used methods for the detection of genotoxic effects of pesticides exposure are target the analysis of DNA and chromosome damage carried out by using tests like Sister Chromatic Exchange assay (Stults et al. 2014), Single-cell gel electrophoresis (Comet) assay, which measures DNA strand breaks in eukaryotic cells (Collins 2004) and fluorescent in situ hybridization assay (Hu et al. 2014) which uses fluorescent probes that bind only to chromosome parts with high degree of sequence complementarity. Fluorescently labeled DNA probes used in in situ hybridization techniques allows visualization and localization of specific genes or chromosome regions of interest within the genome of interphase cell (Mladinic et al. 2012).