Rapid and sensitive detection of Vibrio parahaemolyticus in sea foods by electrochemiluminescence polymerase chain reaction method

Electrochemical DNA Biosensors with Dual-Signal Amplification Strategy for Highly Sensitive HPV 16 Detection

Cervical cancer is an important topic in the study of global health issues, ranking fourth among women's cancer cases in the world. It is one of the nine major cancers that China is focusing on preventing and treating, and it is the only cancer that can be prevented through vaccination. Systematic and effective screening for human papilloma (HPV) infection, which is closely linked to the development of cervical cancer, can reduce cervical cancer incidence and mortality. In this paper, an electrochemical sensor was designed to detect HPV 16 using dual-signal amplification. An APTES-modified glassy carbon electrode was used for improved stability. Gold nanoparticles and a chain amplification reaction were combined for signal amplification. The limit of detection (LOD) of this electrochemical sensor was 1.731 × 10-16 mol/L, and the linear response of the target detector range was from 1.0 × 10-13 mol/L to 1.0 × 10-5 mol/L (R2 = 0.99232). The test of serum sample recovery showed that it has good anti-interference, and the performance of all aspects was improved to different degrees compared with the previous research from the team. The designed sensor is centered around the principles of low cost, high sensitivity and stability, which provides new ideas for the future development of cervical cancer prevention and electrochemical biosensors.

Recent Advances in Electrochemiluminescence Sensors for Pathogenic Bacteria Detection

Pathogenic bacterial contamination greatly threats human health and safety. Rapidly biosensing pathogens in the early stage of infection would be helpful to choose the correct drug treatment, prevent transmission of pathogens, as well as decrease mortality and economic losses. Traditional techniques, such as polymerase chain reaction and enzyme-linked immunosorbent assay, are accurate and effective, but are greatly limited because they are complex and time-consuming. Electrochemiluminescence (ECL) biosensors combine the advantages of both electrochemical and photoluminescence analysis and are suitable for high sensitivity and simple pathogenic bacteria detection. In this review, we summarize recent advances in ECL sensors for pathogenic bacteria detection and highlight the development of paper-based ECL platforms in point of care diagnosis of pathogens.

Visual and sensitive detection of viable pathogenic bacteria by sensing of RNA markers in gold nanoparticles based paper platform

Food-borne pathogens have been recognized as a major cause of human infections worldwide. Their identification needs to be simpler, cheaper and more reliable than the traditional methods. Here, we constructed a low-cost paper platform for viable pathogenic bacteria detection with the naked eye. In this study, an effective isothermal amplification method was used to amplify the hlyA mRNA gene, a specific RNA marker in Listeria monocytogenes. The amplification products were applied to the paper-based platform to perform a visual test using sandwich hybridization assays. When the RNA products migrated along the platform by capillary action, the gold nanoparticles accumulated at the designated area. Under optimized experimental conditions, as little as 0.5 pg/μL genomic RNA from L. monocytogenes could be detected. It could also be used to specifically detect 20 CFU/mL L. monocytogenes from actual samples. The whole assay process, including RNA extraction, amplification, and visualization, can be completed within several hours. This method is suitable for point-of-care applications to detect food-borne pathogens, as it can overcome the false-positive results caused by amplifying nonviable L. monocytogenes. Furthermore, the results can be imaged and transformed into a two-dimensional bar code through an Android-based smart phone for further analysis or in-field food safety tracking.

Rapid and sensitive electrochemiluminescence detection of rotavirus by magnetic primer based reverse transcription-polymerase chain reaction

A novel method for detection of rotavirus has been developed by integrating magnetic primer based reverse transcription-polymerase chain reaction (RT-PCR) with electrochemiluminescence (ECL) detection. This is realized by accomplishing RT of rotavirus RNA in traditional way and performing PCR of the resulting cDNA fragment on the surface of magnetic particles (MPs). In order to implement PCR on MPs and achieve rapid ECL detection, forward and reverse primers are bounded to MPs and tris-(2,2'-bipyridyl) ruthenium (TBR), respectively. After RT-PCR amplification, the TBR labels are directly enriched onto the surface of MPs. Then the MPs-TBR complexes can be loaded on the electrode surface and analyzed by magnetic ECL platform without any post-modification or post-incubation process. So some laborious manual operations can be avoided to achieve rapid yet sensitive detection. In this study, rotavirus in fecal specimens was successfully detected within 1.5 h. Experimental results showed that the detection limit of the assay was 0.2 pg μL(-1) of rotavirus. The ECL intensity was linearly with the concentration from 0.2 pg μL(-1) to 400 pg μL(-1). What's more, the specificity of this method was confirmed by detecting other fecal specimens of patients with nonrotavirus-associated gastroenteritis. We anticipate that the proposed magnetic primer based RT-PCR with ECL detection strategy will find numerous applications in food safety field and clinical diagnosis.