Functionalized reduced graphene oxide as a lateral flow immunoassay label for one-step detection of Escherichia coli O157:H7

In this study, graphene oxide (GO) and reduced graphene oxide (rGO) were used as visual labels in a lateral flow assay for detection of E. coli O157:H7. The color intensity was employed for the quantitative measurements of the target bacteria. Quantitative results showed that in comparison to GO, rGO can provide higher color intensity owing to enhanced light absorption following chemical reduction. Our results confirm that the visual limit of detection of the target bacteria by rGO is ~105 colony forming unit per milliliter (CFU/ml), which closely compares with current alternative techniques using gold nanoparticles. The performance and practicability of the rGO-based test strips for detection of the target bacteria in milk and drinking water were validated with conventional plating and colony counting techniques. Results suggest that the proposed lateral flow assay is sensitive, specific, and affordable. It has also the potential to become a widely used detection technique for E. coli O157:H7 and a wide variety of other analytes.Graphical abstract
Source: Journal of Pharmaceutical and Biomedical Analysis - Category: Drugs & Pharmacology Source Type: research

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Authors: Savaş Şen Z, Taşar MA, Demirel Kaya F, Güneş A, Vezir E, Hızarcıoğlu Gülşen H Abstract Cryptosporidium spp. is one of the leading causes of parasitic diarrhea. It is the most common parasite in humans all over the world with Giardia. Cryptosporidium is an important cause of chronic diarrhea in Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS) patients. Patients with normal immune system may have an asymptomatic course or clinical presentation such as acute watery diarrhea without blood and persistent diarrhea. The severity and duration of the disease may be a re...
Source: Mikrobiyoloji Bulteni - Category: Microbiology Tags: Mikrobiyol Bul Source Type: research
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Source: Mikrobiyoloji Bulteni - Category: Microbiology Tags: Mikrobiyol Bul Source Type: research
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Source: Mikrobiyoloji Bulteni - Category: Microbiology Tags: Mikrobiyol Bul Source Type: research
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Source: Saudi Medical Journal - Category: Middle East Health Tags: Saudi Med J Source Type: research
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Source: Saudi Medical Journal - Category: Middle East Health Tags: Saudi Med J Source Type: research
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Source: Journal of Biotechnology - Category: Biotechnology Source Type: research
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Source: Journal of Microbiological Methods - Category: Microbiology Source Type: research
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Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research
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Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research
Abstract Escherichia coli O157:H7 and Salmonella enterica are foodborne pathogens with major public health concern in the U.S. These pathogens utilize several virulence factors to initiate infections in humans. The antimicrobial effect of seven glucosinolate hydrolysis compounds against Salmonella and E. coli O157:H7 was investigated by the disc diffusion assay. Among the tested compounds, benzyl isothiocyanate (BIT), which exerted the highest antimicrobial activity, was evaluated for its anti-virulence properties against these pathogens. The effect of BIT on motility of Salmonella and E. coli O157:H7 and Shiga to...
Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research
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