A new system for the amplification of biological signals: RecA and complimentary single strand DNA probes on a leaky surface acoustic wave biosensor

Early detection of cervical cancer based on high-risk HPV DNA-based genosensors: A systematic review

Human papillomavirus type (HPV) is a common cause of sexually transmitted disease (STD) in humans. HPV types 16 and 18 as the highest risk types are related with gynecologic malignancy and cervical cancer (CC) among women worldwide. Recently, considerable development of genosensors, which allows dynamic monitoring of hybridization events for HPV-16 and 18, has been a topic of focus by many researchers. In this systematic review, we highlight the route of development of DNA-based genosensory detection methods for diagnosis of high risk of HPV precancer. Biosensor detection methods of HPV-16 and 18 was investigated from 1994 to 2018 using several databases including PubMed, Cochrane Library, Scopus, Google Scholar, SID, and Scientific Information Database. Manual search of references of retrieved articles were also performed. A total of 50 studies were reviewed. By analyzing the most recent developed electrochemical biosensors for the identification of HPV, we observed that the sensor platform fabricated by Wang et al. holds the lowest detection limit reported in the literature for the DNA of HPV-16. Up to this date, optical, electrochemical, and piezoelectric systems are the main transducers used in the development of biosensors. Among the most sensitive techniques available to study the biorecognition activity of the sensors, we highlight the biosensors based fluorescent, EIS, and QCM. The current systematic review focuses on the sensory diagnostic methods that are being used to detect HPV-16 and 18 worldwide. Special emphasis is given on the sensory techniques that can diagnosis the individuals with CC. © 2018 BioFactors, 45(2):101-117, 2019.

The Application of Lipid Membranes in Biosensing

The exploitation of lipid membranes in biosensors has provided the ability to reconstitute a considerable part of their functionality to detect trace of food toxicants and environmental pollutants. This paper reviews recent progress in biosensor technologies based on lipid membranes suitable for food quality monitoring and environmental applications. Numerous biosensing applications based on lipid membrane biosensors are presented, putting emphasis on novel systems, new sensing techniques, and nanotechnology-based transduction schemes. The range of analytes that can be currently using these lipid film devices that can be detected include, insecticides, pesticides, herbicides, metals, toxins, antibiotics, microorganisms, hormones, dioxins, etc. Technology limitations and future prospects are discussed, focused on the evaluation/validation and eventually commercialization of the proposed lipid membrane-based biosensors.

Highly sensitive detection of lipopolysaccharides using an aptasensor based on hybridization chain reaction

Lipopolysaccharides (LPS), integral components of the outer membrane of all gram-negative bacteria, are closely associated with foodborne diseases such as fever, diarrhea and hypotension, and thus, the early and sensitive detection of LPS is necessary. In this study, an aptasensor assay based on hybridization chain reaction (HCR) was developed to detect LPS. Briefly, two complementary stable species of biotinylated DNA hairpins coexisted in solution until the introduction of a detection probe triggered a hybridization chain reaction cascade. The DNA conjugates specifically reacted with the LPS, which were captured by the ethanolamine aptamer attached to the reaction well surface. After optimizing the key reaction conditions, such as the reaction time of HCR, the amount of the capture probe and detection probes, the increase in the LPS concentration was readily measured by the optical density value, and a relatively low detection limit (1.73 ng/mL) was obtained, with a linear response range of 1–10⁵ng/mL. The approach presented herein introduced the use of an aptasensor for LPS discrimination and HCR for signal amplification, offering a promising option for detecting LPS.

A Sensitive and Selective Label-Free Electrochemical DNA Biosensor for the Detection of Specific Dengue Virus Serotype 3 Sequences

Dengue fever is the most prevalent vector-borne disease in the world, with nearly 100 million people infected every year. Early diagnosis and identification of the pathogen are crucial steps for the treatment and for prevention of the disease, mainly in areas where the co-circulation of different serotypes is common, increasing the outcome of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Due to the lack of fast and inexpensive methods available for the identification of dengue serotypes, herein we report the development of an electrochemical DNA biosensor for the detection of sequences of dengue virus serotype 3 (DENV-3). DENV-3 probe was designed using bioinformatics software and differential pulse voltammetry (DPV) was used for electrochemical analysis. The results showed that a 22-m sequence was the best DNA probe for the identification of DENV-3. The optimum concentration of the DNA probe immobilized onto the electrode surface is 500 nM and a low detection limit of the system (3.09 nM). Moreover, this system allows selective detection of DENV-3 sequences in buffer and human serum solutions. Therefore, the application of DNA biosensors for diagnostics at the molecular level may contribute to future advances in the implementation of specific, effective and rapid detection methods for the diagnosis dengue viruses.

A Review of Membrane-Based Biosensors for Pathogen Detection

Biosensors are of increasing interest for the detection of bacterial pathogens in many applications such as human, animal and plant health, as well as food and water safety. Membranes and membrane-like structures have been integral part of several pathogen detection platforms. Such structures may serve as simple mechanical support, function as a part of the transduction mechanism, may be used to filter out or concentrate pathogens, and may be engineered to specifically house active proteins. This review focuses on membrane materials, their associated biosensing applications, chemical linking procedures, and transduction mechanisms. The sensitivity of membrane biosensors is discussed, and the state of the field is evaluated and summarized.