Emergency sensors and biosensors Dotaz Zobrazit nápovědu
Selective, sensitive and affordable techniques to detect disease and underlying health issues have been developed recently. Biosensors as nanoanalytical tools have taken a front seat in this context. Nanotechnology-enabled progress in the health sector has aided in disease and pandemic management at a very early stage efficiently. This report reflects the state-of-the-art of nanobiosensor-based virus detection technology in terms of their detection methods, targets, limits of detection, range, sensitivity, assay time, etc. The article effectively summarizes the challenges with traditional technologies and newly emerging biosensors, including the nanotechnology-based detection kit for COVID-19; optically enhanced technology; and electrochemical, smart and wearable enabled nanobiosensors. The less explored but crucial piezoelectric nanobiosensor and the reverse transcription-loop mediated isothermal amplification (RT-LAMP)-based biosensor are also discussed here. The article could be of significance to researchers and doctors dedicated to developing potent, versatile biosensors for the rapid identification of COVID-19. This kind of report is needed for selecting suitable treatments and to avert epidemics.
Polyamines (PAs) are involved in a variety of fundamental physio-pathologic processes. The concentration of these polycations in organs and tissues depends on their endogenous production and oxidation rates, and on their intake from foods. Besides being largely accepted as markers for the progress of several pathologies, PAs may exert themselves different effects on humans, ranging from being positive to be drastically detrimental depending on the organism conditions. Thus, if the determination of polyamines content in tissue samples is of great importance as they could be indicators of several diseases, their quantification in food is fundamental for modulating the diet to respond to a specific human health status. Thus, the determination of PA content in food is increasingly urgent. Standard analytical methods for polyamine quantification are mainly based on chromatography, where high-performance liquid chromatography and gas chromatography are the most often used, involving pre-column or post-column derivatization techniques. Driven by the growing need for rapid in situ analyses, electrochemical biosensors, comprising various combinations of different enzymes or nanomaterials for the selective bio-recognition and detection, are emerging as competitors of standard detection systems. The present review is aimed at providing an up-to-date overview on the recent progresses in the development of sensors and biosensors for the detection of polyamines in human tissues and food samples. Basic principles of different electrochemical (bio)sensor formats are reported and the applications in human tissues and in foods was evidenced.
Polymer brushes are frequently used as surface-tethered antifouling layers in biosensors to improve sensor surface-analyte recognition in the presence of abundant non-target molecules in complex biological samples by suppressing nonspecific interactions. However, because brushes are complex systems highly responsive to changes in their surrounding environment, studying their properties remains a challenge. Electrochemical impedance spectroscopy (EIS) is an emerging method in this context. In this mini review, we aim to elucidate the potential of EIS for investigating the physicochemical properties and structural aspects of polymer brushes. The application of EIS in brush-based biosensors is also discussed. Most common principles employed in these biosensors are presented, as well as interpretation of EIS data obtained in such setups. Overall, we demonstrate that the EIS-polymer brush pairing has a considerable potential for providing new insights into brush functionalities and designing highly sensitive and specific biosensors.
- MeSH
- biosenzitivní techniky * MeSH
- impedanční spektroskopie * MeSH
- polymery MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Tumor Necrosis Factor Alpha (TNFα) is an important marker of inflammatory processes in human body. In the current healthcare, determination of TNFα blood or plasma level is done by Enzyme Linked Immuno-Sorbent Assay (ELISA) as a primary choice method. Piezoelectric immunosensors are analytical platform recording affinity interactions on their surface. It is inferred that the immunosensors would be a functional alternative to the ELISA. In this study, antibody against TNFα was immobilized on Quartz Crystal Microbalance (QCM) sensor and the same was made on magnetic particles. Human TNFα was measured in a way of interaction with QCM surface and then the particles were applied. The assay exerted sufficient limit of detection equal to 1.62pg/ml and it also fully correlated with standard ELISA tests. No interference by interleukin 6 or albumin was observed. Long term stability of the immunosensors lasting for at least three months was found. The immunosensors appears to be readily for practical performance and it would be an alternative to the standard ELISA especially when diagnoses made in field, homecare conditions or conditions of small hospitals as an emergency test.
With the increased demand for beef in emerging markets, the development of quality-control diagnostics that are fast, cheap and easy to handle is essential. Especially where beef must be free from pork residues, due to religious, cultural or allergic reasons, the availability of such diagnostic tools is crucial. In this work, we report a label-free impedimetric genosensor for the sensitive detection of pork residues in meat, by leveraging the biosensing capabilities of graphene acid - a densely and selectively functionalized graphene derivative. A single stranded DNA probe, specific for the pork mitochondrial genome, was immobilized onto carbon screen-printed electrodes modified with graphene acid. It was demonstrated that graphene acid improved the charge transport properties of the electrode, following a simple and rapid electrode modification and detection protocol. Using non-faradaic electrochemical impedance spectroscopy, which does not require any electrochemical indicators or redox pairs, the detection of pork residues in beef was achieved in less than 45 min (including sample preparation), with a limit of detection of 9% w/w pork content in beef samples. Importantly, the sample did not need to be purified or amplified, and the biosensor retained its performance properties unchanged for at least 4 weeks. This set of features places the present pork DNA sensor among the most attractive for further development and commercialization. Furthermore, it paves the way for the development of sensitive and selective point-of-need sensing devices for label-free, fast, simple and reliable monitoring of meat purity.
Surface plasmon resonance (SPR) biosensors capable of in real time detection of Cronobacter at concentrations down to 10⁶ cells mL⁻¹ in samples of consumer fresh-whole fat milk, powder whole-fat milk preparation, and powder infant formulation were developed for the first time. Antibodies against Cronobacter were covalently attached onto polymer brushes of poly(2-hydroxyethyl methacrylate) (poly(HEMA)) grafted from the SPR chip surface. The lowest detection limit, 10⁴ cells mL⁻¹, was achieved in phosphate buffered saline (pH 7.4) with sensors prepared by covalent immobilization of the same antibodies onto a self assembled monolayer (SAM) of hexa(ethylene glycol) undecanethiol (EG₆). However, when the EG₆ based sensors were challenged with milk samples the non-specific response due to the deposition of non-targeted compounds from the milk samples was much higher than the specific response to Cronobacter hampering the detection in milk. Similar interfering fouling was observed on antifouling polymer brushes of hydroxy-capped oligoethylene glycol methacrylate and even a 10 times higher fouling was observed on the widely used SAM of mixed hydroxy- and carboxy-terminated alkanethiols. Only poly(HEMA) brushes totally suppressed the fouling from milk samples. The robust well-controlled surface initiated atom transfer radical polymerization of HEMA allowed the preparation of highly dense brushes with a minimal thickness so that the capture of antigens by the antibodies immobilized on the brush layer could take place close to the gold SPR surface to provide a stronger optical response while the fouling was still suppressed. A minimum thickness of 19 nm of poly(HEMA) brush layer was necessary to suppress completely non-specific sensor response to fouling from milk.
- MeSH
- Enterobacteriaceae izolace a purifikace patogenita MeSH
- imobilizační protilátky MeSH
- kojenec MeSH
- lidé MeSH
- limita detekce MeSH
- mléko mikrobiologie MeSH
- náhražky mateřského mléka MeSH
- polyhydroxyethylmethakrylát MeSH
- potravinářská mikrobiologie metody statistika a číselné údaje MeSH
- povrchová plasmonová rezonance metody statistika a číselné údaje MeSH
- protilátky bakteriální MeSH
- zlato MeSH
- zvířata MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
