Isothermal DNA amplification with functionalized graphene and nanoparticle assisted electroanalysis for rapid detection of Johne's disease
Chand, Rohit ; Wang, Yi Lan ; Kelton, David ; Neethirajan, Suresh - \ 2018
Sensors and Actuators B: Chemical 261 (2018). - ISSN 0925-4005 - p. 31 - 37.
Biosensor - Electrochemical detection - Graphene - Johne's disease - LAMP - ZrO nanoparticles
Johne's disease (JD), which is caused by Mycobacterium avium subspecies paratuberculosis (MAP), is a bacterial infection of the intestinal tract of ruminants. JD is a cause of significant economic and animal loss throughout the world. Sensitive, selective, and on-site detection of MAP in clinical samples has always been a problem. This study outlines a loop-mediated isothermal DNA amplification (LAMP) and electrochemical analysis-based point-of-care (POC) detection methodology for MAP. LAMP contributed to the selective amplification of MAP DNA, and electrochemical analysis assisted in the rapid and sensitive analysis of LAMP products. A graphene and tetracycline (TET)-functionalized screen printed carbon electrode was used for the selective detection of magnesium pyrophosphate (Mg2P2O7) produced during the LAMP. The Mg2P2O7 obtained from the LAMP was sandwiched on the electrode between TET and zirconium dioxide nanoparticles (ZrO2). The complexation of Mg2P2O7 triggered an electrochemical change that was monitored using electrochemical techniques. The complexation mechanism and functionalized electrodes were characterized using several microscopic, spectroscopic, and electrochemical techniques. The optimized MAP biosensor was employed to detect a range of MAP DNA concentrations. Using electrochemical impedance spectroscopy, a detection limit of 6.37 aM (20 fg/μL) with a detection range of 6.37 aM (20 fg/μL) to 6.37 pM (20 ng/μL) for MAP DNA was obtained. The application of the biosensor was also assessed by MAP detection in clinical fecal samples. The biosensor could easily detect the presence of MAP in bovine fecal samples and showed good co-relation with other conventional techniques. Therefore, the developed biosensor has the potential to be used for POC detection of JD in animals.
Agro-defense: Biosensors for food from healthy crops and animals
Neethirajan, Suresh ; Ragavan, K.V. ; Weng, Xuan - \ 2018
Trends in Food Science and Technology 73 (2018). - ISSN 0924-2244 - p. 25 - 44.
Agro-defense - Animal health - Biosensor - Human food - Infectious pathogen - Plant health
Background: Infectious diseases are a leading cause of death in humans, animals, and plants globally. Pathogen infections can reduce food production and endanger biodiversity. Viruses, bacteria, and fungi are therefore scientifically and economically important in food production. Even outbreaks of a pathogen infection in plants or animals have direct consequences for the food chain and human health. Scope and approach: Microorganisms such as bacteria, fungi and virus invade plant cells and utilize the host resources for their survival disturbing the plant or animal metabolism leading to diseases. Advance diagnosis and effective detection of pathogens, infectious diseases, and other parameters affecting the health of animals and plants in agro-defense will assist in reducing financial costs, increasing food production, and improving the global economy. In this article, common pathogens and infectious diseases in animals and plants, along with the point-of-care technologies that address them, are reviewed. Key findings and conclusions: The synthesis and discovery of novel nanomaterials and the fabrication of highly specific and sensitive biosensors have expanded the scope for effective agro-defense biosensors. Progress in biosensor development and the existing challenges are reviewed to provide future directions in this field.
Nano-biosensor platforms for detecting food allergens – New trends
Neethirajan, S. ; Weng, X. ; Tah, A. ; Cordero, J.O. ; Ragavan, K.V. - \ 2018
Sensing and Bio-Sensing Research 18 (2018). - ISSN 2214-1804 - p. 13 - 30.
Aptamer - Biosensor - Food allergen - Food allergy - Nanomaterial - Point-of-care
Food allergies are a type I hypersensitivity immune responses that can be life threatening. While exposure therapy and urgent care interventions can limit the damage of an allergic episode, there is currently no cure for food hypersensitivities. Many patients will experience an accidental exposure to a known allergen due to the complexity of food preparation methods in the modern diet. One method of avoidance is to monitor food with point of care (POC) biosensors that can detect known allergens. These detectors are categorized according to their sensor mechanism, such as optical, electromechanical, and electrochemical biosensors. More innovations that are recent combine biosensors with genosensors and cell assays. Major challenges to allergen monitoring include the introduction of new allergens into modern diets, the rising incidence hypersensitivities, lack of clinical understanding of the types and causes of food allergies, limited commercial availability of biosensors, and the lack of international standards or agreement on threshold detection levels. Public health leaders are taking on these challenges, and their efforts will reduce the incidence of preventable exposures and improve overall food safety management.
BIOFOS: micro-ring resonator-based biophotonic system for food analysis. Nut mycotoxin detection
Romero, A. ; Ninot, A. ; Hermoso, J.F. ; Zergioti, I. ; Kouloumentas, Ch. ; Avramopoulos, H. ; Leeuwis, H. ; Schreuder, E. ; Graf, S. ; Knapp, H. ; Barthelmebs, L. ; Noguer, T. ; Tsekenis, G. ; Scheres, L. ; Smulders, M. ; Zuilhof, H. ; Heesink, G. ; Reguillo, L. ; Risquez, A. - \ 2018
In: Proceedings of the 7th International Symposium on Almonds and Pistachios. - International Society for Horticultural Science (Acta Horticulturae ) - ISBN 9789462612167 - p. 339 - 343.
Analysis of aflatoxin B1 - Biosensor - Food safety
BIOFOS aims to further develop and validate a reusable and high-added value Lab-on-Chip (LoC) based, micro-biophotonic sensor platform for in situ monitoring of food contaminants. The Lab-on-Chip was tested on milk (aflatoxin M1, antibiotics and lactose), olive oil (pesticides and metals), nuts (aflatoxin B1) and dehydrated fruits (ochratoxin A). BIOFOS combines the most promising concepts from the photonic, biological, nanochemical and fluidic parts of Lab-on-Chip systems, aiming to achieve low sensitivity and high specificity, excellent reliability and compactness. Current methodologies for detection of food contamination based on heavy analytical tools cannot guarantee a safe and stable food supply. The reasons are the complexity, the long time-to-result (2-3 days) and the cost of these tools, which limit the number of samples that can be practically analyzed at food processing and storage sites. Preliminary results for almonds spiked with aflatoxin B1 are presented. First results suggest that BIOFOS has sensitivity enough for AFB1, even that the concentration is at ppb level. More data are still required, and many analyses are ongoing in the laboratory. Results are not enough to conclude about any characteristics of the device performance, even then repeatability seems very good (variation less than 3% at 25 ppb) and recovery is acceptable (78.4%), while decision limit and detection capability are still uncertain.
Aptamer-based fluorometric determination of norovirus using a paper-based microfluidic device
Weng, Xuan ; Neethirajan, Suresh - \ 2017
Microchimica acta 184 (2017)11. - ISSN 0026-3672 - p. 4545 - 4552.
Aptamer - Biosensor - Graphene oxide - Multi-walled carbon nanotubes - Nitrocellulose membrane - Norovirus - Paper-based microfluidic device
The authors describe a rapid and highly sensitive point-of-care device for rapid determination of noroviruses, a leading cause of acute gastroenteritis. The assay is based on the use of a norovirus-specific aptamer labeled with 6-carboxyfluorescein, and of multi-walled carbon nanotubes (MWCNT) and graphene oxide (GO). The fluorescence of the 6-FAM labeled aptamer is quenched by MWCNT or GO. In the presence of norovirus, fluorescence is recovered due to the release of the labeled aptamer from MWCNT or GO. An easy-to-make paper-based microfluidic platform was developed using a nitrocellulose membrane. The quantitation of norovirus was successfully performed. The linear range extends from 13 ng·mL−1 to 13 μg·mL−1 of norovirus. The detection limits are 4.4 ng·mL−1 and 3.3 ng·mL−1, respectively, when using MWCNT or GO. The device is simple and cost-effective, and holds the potential of rapid in-situ visual determination of noroviruses with remarkable sensitivity and specificity. Hence, it provides a new method for early identification of norovirus and a tool for early intervention when preventing the spread of an outbreak. [Figure not available: see fulltext.].
Recent advances in biosensor development for foodborne virus detection
Neethirajan, Suresh ; Ahmed, Syed Rahin ; Chand, Rohit ; Buozis, John ; Nagy, Éva - \ 2017
Nanotheranostics 1 (2017)3. - p. 272 - 295.
Biosensor - Foodborne virus - Microfluidics - Nanomaterials - Point-of-care
Outbreaks of foodborne diseases related to fresh produce have been increasing in North America and Europe. Viral foodborne pathogens are poorly understood, suffering from insufficient awareness and surveillance due to the limits on knowledge, availability, and costs of related technologies and devices. Current foodborne viruses are emphasized and newly emerging foodborne viruses are beginning to attract interest. To face current challenges regarding foodborne pathogens, a point-of-care (POC) concept has been introduced to food testing technology and device. POC device development involves technologies such as microfluidics, nanomaterials, biosensors and other advanced techniques. These advanced technologies, together with the challenges in developing foodborne virus detection assays and devices, are described and analysed in this critical review. Advanced technologies provide a path forward for foodborne virus detection, but more research and development will be needed to provide the level of manufacturing capacity required.
Dietary supplement for energy and reduced appetite containing the β-agonist isopropyloctopamine leads to heart problems and hospitalisations
Bovee, Toine F.H. ; Mol, Hans G.J. ; Bienenmann-Ploum, Monique E. ; Heskamp, Henri H. ; Bruchem, Gerard D. van; Ginkel, Leendert A. van; Kooijman, Martin ; Lasaroms, Johan J.P. ; Dam, Ruud van; Hoogenboom, Ron L.A.P. - \ 2016
Food Additives & Contaminants. Pt. A, Chemistry, Analysis, Control, Exposure & Risk Assessment 33 (2016)5. - ISSN 1944-0049 - p. 749 - 759.
Biosensor - enforcement - health risks - internet - supplements - web shops
In 2013 the Dutch authorities issued a warning against a dietary supplement that was linked to 11 reported adverse reactions, including heart problems and in one case even a cardiac arrest. In the UK a 20-year-old woman, said to have overdosed on this supplement, died. Since according to the label the product was a herbal mixture, initial LC-MS/MS analysis focused on the detection of plant toxins. Yohimbe alkaloids, which are not allowed to be present in herbal preparations according to Dutch legislation, were found at relatively high levels (400–900 mg kg–1). However, their presence did not explain the adverse health effects reported. Based on these effects the supplement was screened for the presence of a β-agonist, using three different biosensor assays, i.e. the validated competitive radioligand β2-adrenergic receptor binding assay, a validated β-agonists ELISA and a newly developed multiplex microsphere (bead)-based β-agonist assay with imaging detection (MAGPIX®). The high responses obtained in these three biosensors suggested strongly the presence of a β-agonist. Inspection of the label indicated the presence of N-isopropyloctopamine. A pure standard of this compound was bought and shown to have a strong activity in the three biosensor assays. Analysis by LC-full-scan high-resolution MS confirmed the presence of this ‘unknown known’ β3-agonist N-isopropyloctopamine, reported to lead to heart problems at high doses. A confirmatory quantitative analysis revealed that one dose of the preparation resulted in an intake of 40–60 mg, which is within the therapeutic range of this compound. The case shows the strength of combining bioassays with chemical analytical techniques for identification of illegal pharmacologically active substances in food supplements.