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Nanomaterials and devices for the provision of safe drinking water in rural communities
Published in Manish Kumar, Sanjeeb Mohapatra, Kishor Acharya, Contaminants of Emerging Concerns and Reigning Removal Technologies, 2022
David F. L. Jenkins, Jonathan M. Bloor, Bing Li, Vikram S. Raghaven, Richard D. Handy, Shivaraju Harikaranahalli Puttaiah, Awadhesh N. Jha, Sai S. Gorthi
Modern technologies have emerged for diagnosis of pathogenic microorganisms (Rajapaksha et al., 2019 and Leonard et al., 2003). A class of pathogenic viruses, bacteria and fungi exist in the environment, which can cause potential harm to humans and animals (Pachepsky et al., 2011). Early diagnostics of pathogenic microbes is highly essential to ensure proper therapy. Immunological (Schloter et al., 1995) and molecular diagnostics (Toze, 1999) act as promising tools and are widely used to identify the pathogens. Fluorescence spectroscopy was explored in combination with antibodies and DNA-based detection of pathogenic microbes (Cumberland et al., 2012). This technique typically utilises specific antibodies or DNA sequences to identify microorganisms of interest. Diagnostics methods such as mass spectrometry (Sauer and Kliem, 2010), polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) (Martzy et al., 2017) can replace time-consuming techniques, which also require rigorous sample preparation mechanisms. These techniques can rapidly detect pathogenic microorganisms with high-level accuracy. Integrating automation of sample processing with Fluorescence, PCR, LAMP and mass spectrometry techniques can drastically reduce analysis time and the results can be achieved at high accuracy (Zhang et al., 2018).
Next-Generation Immunoassays
Published in Richard O’Kennedy, Caroline Murphy, Immunoassays, 2017
Valerie Fitzgerald, Paul Leonard
There are a number of characteristics of the LAMP method that make it superior to other similar methods. Firstly, unlike other PCR-based methods, LAMP does not require high-precision thermal cycling equipment due to the use of an isothermal enzyme. Secondly, the simplified reaction, which occurs in one tube, can be monitored and a positive reaction confirmed in a number of ways, either by turbidity or by fluorescence, without complicated or time-consuming post-amplification analysis [52]. These properties make LAMP a very attractive method for diagnosis of disease and infection in instances where sophisticated equipment and highly skilled personnel are not available. A very interesting modification of the LAMP method, described by Lee et al., outlines a reverse-transcription loop-mediated isothermal amplification–enzyme-linked immunosorbant hybridisation (RT-LAMP-ELISA) assay for the detection of Mycobacterium tuberculosis in patient samples. With this technique the authors detail a rapid, ‘one-tube’ method for detection of active tuberculosis in patients as well as the ability to differentiate M. tuberculosis from other Mycobacteria species from a single sputum sample [51].
Aptamers in Medical Diagnosis
Published in Rakesh N. Veedu, Aptamers, 2017
Veli Cengiz Ozalp, Murat Kavruk, Ozlem Dilek, Abdullah Tahir Bayrac
The promising potential of a SOMAmer can be deduced from a recent cooperation between Somalogic and New England Biolabs (NEB) when they announced to develop PCR reagents incorporated with SOMAmers for the reverse transcriptase (RTx) enzyme. By coupling a reversibly bound aptamer that inhibits RTx activity below 40°C, NEB has marketed WarmStart® RTx Reverse Transcriptase in 2014 for RNA detection, and specifically for loop-mediated isothermal amplification (LAMP) reactions with high throughput, room temperature, setup capability, and increased specificity [59]. This invention would open new possibilities to early detection of analytes related with diseases. Potential applications of SOMAmers in protein assays, disease detection, and other biotechnoloy areas have recently been reviewed in detail elsewhere [71, 100].
Pathogen contamination of groundwater systems and health risks
Published in Critical Reviews in Environmental Science and Technology, 2023
Yiran Dong, Zhou Jiang, Yidan Hu, Yongguang Jiang, Lei Tong, Ying Yu, Jianmei Cheng, Yu He, Jianbo Shi, Yanxin Wang
Different isothermal amplification techniques demonstrate enhanced DNA amplification efficacy and sensitivity than conventional PCR. In loop-mediated isothermal amplification (LAMP), DNA synthesis is catalyzed by Bst DNA polymerase through autocycling strand displacement at the constant temperature of 60–65 °C, which can achieve a 109-fold increase of the genes of interest within 15–60 min. This rapid and highly sensitive approach has been employed to monitor ultra-low concentrations of pathogens including the SARS-CoV-2 virus (Huang et al., 2020), E. coli (Hara-Kudoa et al., 2008), and Acinetobacter baumannii (Li et al., 2015). In a recent study, a one-pot loop probe-mediated isothermal amplification scheme (oLAMP) was coupled with concurrent target-specific detection readout, by which as low as 1 copy/μL of SARS-CoV-2 gene and the drug-resistant genes for Salmonella were successfully detected (Lu et al., 2022).
Environmental sampling for disease surveillance: Recent advances and recommendations for best practice
Published in Journal of the Air & Waste Management Association, 2023
Joshua L. Santarpia, Elizabeth Klug, Ashley Ravnholdt, Sean M. Kinahan
Several techniques to determine the presence of an infectious agent are summarized in Table 2. Confident identification of an agent can be made by: i) polymerase chain reaction (PCR) or loop-mediated isothermal amplification (LAMP) (Notomi et al. 2000), where a unique fragment of the organism’s DNA or RNA is recognized by short RNA or DNA strands (Fredricks and Relman 1999); ii) immunoassay, where antigenic proteins of the organism are recognized by antibodies (Andreotti et al. 2003); iii) sequencing, where all or large fragments of the organism’s genome are read and recognized (Duan et al. 2021); and iv) clustered regularly interspaced short palindromic repeats (CRISPR) based assays where guide-RNAs recognize specific segments of the organisms genome and an engineered enzyme reports binding of the guides (Yin et al. 2021). Beyond the advancements of isothermal nucleic acid amplification techniques, like LAMP, and the modification of Cas enzymes enabling CRISPR techniques to be used for detection purposes, there have been interesting advances in PCR techniques, as well. One potentially important advance is in digital droplet PCR (ddPCR) (Hindson et al. 2011). In ddPCR, the PCR reaction is done in an emulsion to create tens of the thousands of individual nanoliter PCR reactions. Shrinking the individual reaction volumes to the point where single copies of the target sequence are in each droplet enables quantification of low-abundance nucleic acids. This technique has been applied to environmental samples with some success (Kokkoris et al. 2021).
Gold nanoparticles as radiosensitizer for radiotherapy and diagnosis of COVID-19: A review
Published in Nanoscale and Microscale Thermophysical Engineering, 2022
Abdul Khaliq Mokhtar, Norsyahidah Mohd Hidzir, Faizal Mohamed, Irman Abdul Rahman, Syazwani Mohd Fadzil, Afifah Mardhiah Mohamed Radzi, Nur Ain Mohd Radzali
The reverse transcription-polymerase chain reaction (RT-PCR) test in molecular testing category is currently the litmus test for pathogen detection, in this case, COVID-19 outbreak [178]. However, RT-PCR possesses a few drawbacks, which include false negatives, existence of asymptomatic carriers, complexity, and concerns associated with its replication, responsiveness, and precision [179, 180]. In addition, there is a lack of RT-PCR kits and insufficient medical personnel to operate and perform testing in numerous developing countries, which raises concerns and burdens for them to adopt RT-PCR testing [181]. Some people may also feel uncomfortable, particularly children, as deep nasal swabs are required. Thus, recent advancements and approaches in nanotechnology-based pathogen detection methods have paved the way for more appropriate and simpler options for detecting pathogens in faster and efficient manners [182, 183]. Table 3 shows the diagnostic of coronavirus by AuNP-based approach. As regards enhancing the performance of detecting virus, AuNP has been used in various virus detection systems such as the colloidal gold immunochromatography assay (GICA) [188, 193], reverse transcription loop-mediated isothermal amplification (RT-LAMP) [194, 195], enzyme-linked immunosorbent assay (ELISA) [188, 196], and lateral flow [186, 197] due to its ultrasmall size and large surface area.