Kirigami tripod-based electrode for the development of highly stretchable dengue aptasensor.

Kirigami is one of the interesting paper art forms and the modified sub-class of origami. Kirigami paper art is widely employed in a variety of applications, and it is currently being used in biosensors because of its outstanding advantages. This is the first study on the use of a Kirigami-based aptasensor for DENV (Dengue virus)-antigen detection. In this study, the kirigami approach has been utilized to develop a stretchable, movable, and flexible sensor. The constructed stretchable-kirigami electrode helps in adjusting the connection of electrodes without disturbing the electrochemical cell zone during the experiment. To increase the sensitivity of this biosensor we have synthesized Ag-NPs (Silver nanoparticles) via chemical methods and characterized their results with the help of TEM & UV-Vis Spectroscopy. Different electrochemical approaches were used to validate the sensor response i.e., CV (Cyclic voltammetry) and LSV (Linear sweep voltammetry), which exhibited great detection capability towards dengue virus with the range of 0.1 µg/ml to 1000 µg/ml along with a detection limit of 0.1 µg/ml and showing no reactivity to the chikungunya virus antigen, making it more specific to the DENV antigen. Serum (healthy-human) was also successfully applied to validate the results of the constructed aptasensor. Integration of the Kirigami approach form with the electrochemical aptasensor that utilizes a 3-E setup (three-electrode setup) which is referred to as a tripod and collectively called Kirigami-tripod-based aptasensor. Thus, the developed integrated platform improves the sensors capabilities in terms of cost efficiency, high stretchability, and sensitivity.

Smartphone-Integrated Wireless Portable Potentiostat to Develop 5th-Generation Dengue Pocket Aptasensor toward Portronicx-Approach.

Smartphones' widespread availability and worldwide connection are advancing the idea of mobile-based healthcare and promise to transform the business of biosensors. Biosensors based on smartphones have been investigated in several ways, including employing a smartphone in place of a detector or as an instrumental interface. The current work demonstrates the first successful detection of dengue virus using a smartphone-based pocket sensor combined with a wireless potentiostat. The platform developed comprises a smartphone, a wireless portable potentiostat, an Android app, and a three-electrode setup. The combination of portable diagnostic with electronic application is referred to as "Portronicx", and this is the first time that the term "Portronicx" has been used in a dengue sensor, so the current study has the potential to be commercialized in the market with the tag line "Portronicx-commercialization" in the future. Miniaturization improves alternative setup options in terms of instrument size, affordability, mobility, touch-mobile display, and design versatility. The current work proved the excellent combination of a wireless potentiostat with an aptasensor to detect dengue antigen within 20 s with good LOD (0.1 µg/mL) and easy to carry in their pockets. The created platform also performed effectively in human serum. This study replaced all of the instruments with a lightweight touch smartphone, paving the way for the production of fifth-generation electrochemical aptasensors, with potential implications for healthcare applications on the verge of commercialization.

Ternary Nanostructure Coupling Flip-Flap Origami-Based Aptasensor for the Detection of Dengue Virus Antigens.

There is currently a lot of interest in the construction of point-of-care devices stemming from paper-based origami biosensors. These devices demonstrate how paper's foldability permits the construction of sensitive, selective, user-friendly, intelligent, and maintainable analytical devices for the detection of several ailments. Herein, the first example of the electrochemical aptasensor-based polyvalent dengue viral antigen detection using the origami paper-folding method is presented. Coupling it with an aptamer leads to the development of a new notation known as OBAs, or origami-based aptasensor, that presents a multitude of advantages to the developed platform, such as assisting in safeguarding the sample from air-dust particles, providing confidentiality, and providing a closed chamber to the electrodes. In this paper, gold-decorated nanocomposites of zinc and graphene oxide (Au/ZnO/GO) were synthesized via the chemical method, and characterization was conducted by Scanning Electron Microscope, Transmission Electron Microscope, UV-Vis, and XRD which reveals the successful formation of nanocomposites, mainly helping to enhance the signal and specificity of the sensor by employing aptamers, since isolation and purification procedures are not required. The biosensor that is being demonstrated here is affordable, simple, and efficient. The reported biosensor is an OBA detection of polyvalent antigens of the dengue virus in human serum, presenting a good range from 0.0001 to 0.1 mg/mL with a limit of detection of 0.0001 mg/mL. The reported single-folding ori-aptasensor demonstrates exceptional sensitivity, specificity, and performance in human serum assays, and can also be used for the POC testing of various viral infections in remote areas and underdeveloped countries, as well as being potentially effective during outbreaks. Highlights: (1) First report on origami-based aptasensors for the detection of polyvalent antigens of DENV; (2) In-house construction of low-cost origami-based setup; (3) Gold-decorated zinc/graphene nanocomposite characterization was confirmed via FESEM/UV-Vis/FTIR; (4) Cross-reactivity of dengue-aptamer has been deduced; (5) Electrochemical validation was conducted through CV.

Mitigation of the Deleterious Effect of Heavy Metals on the Conformational Stability of Ubiquitin through Osmoprotectants.

The Ubiquitin-Proteasome System (UPS) is important in protein homeostasis and is involved in many cell processes. UPS's wide range of regulatory activities is based on the unique and diverse signals transmitted through all-encompassing processes. Cells need a fully functional UPP to cope with oxidative stress, so cellular redox status modulates ubiquitin activity. However, these protein quality control systems are compromised under adverse conditions such as heavy metal stress, resulting in pathological conditions. Heavy metals disrupt the physiological action of sensitive proteins by forming complexes with side-chain functional groups or by dislocating critical metal ions in metalloproteins. In addition, perturbation in the structure of Ubiquitin may affect the ubiquitin-proteasome pathway. In this study, it has been investigated the effects of heavy metals likewise chromium (Cr), cadmium (Cd), and mercury chloride (HgCl2) on the conformational stability of Ubiquitin as well as overcome their hazardous effect, the interaction of osmo-protectants such as Sesamol, gallic acid, Glycine, and ascorbic acid have also been explored in the study. The near and far UV-circular dichroism measurements deduced the secondary and tertiary structural changes. The size of the Ubiquitin before and after exposure to heavy metals was measured by DLS (dynamic light scattering). Docking research was also used to investigate the interaction of Ubiquitin with various heavy metals. Near and far UV-circular dichroism (CD) measurements revealed that mercury, chromium, and cadmium disrupt Ubiquitin's secondary and tertiary structure. The effect of chromium, even at low concentrations, was significantly deleterious compared to cadmium and mercury chloride. Ubiquitin's far-UV circular dichroism spectra subjected to heavy metals were recorded in several osmo-protectants, such as ascorbic acid, Glycine, gallic acid, and Sesamol, which offset the adverse effects of heavy metals. DLS studies revealed a noteworthy change in the hydrodynamic radius of Ubiquitin in the presence of heavy metals. Docking analysis revealed a significant binding affinity of mercury and cadmium ions with Ubiquitin. This study can infer the heavy metals' disruption of Ubiquitin's secondary and tertiary structure. Osmo-protectants produced by animal cells are more effective against heavy metals than plant antioxidants.

Papertronics: Marriage between Paper and Electronics Becoming a Real Scenario in Resource-Limited Settings.

Integrating electronic applications with paper, placed next to or below printed images or graphics, can further expand the possible uses of paper substrates. Consuming paper as a substrate in the field of electronics can lead to significant innovations toward papertronics applications as paper comprises various advantages like being disposable, inexpensive, biodegradable, easy to handle, simple to use, and easily available. All of these advantages will definitely spur the advancement of the electronics field, but unfortunately, putting electronics on paper is not an easy task because, compared to plastics, the paper surface is not just rough but also porous. For example, in the case of lateral flow assay testing the sensor response is delayed if the pore size of the paper is enormous. This might be a disadvantage for most electrical devices printed directly on paper. Still, some methods make it compatible when fit with a rough, absorbent surface of the paper. Building electronic devices on a standard paper substrate have sparked much interest because of its lightweight, environmental friendliness, minimal cost, and simple fabrication. A slew of improvements have been achieved in recent years to make paper electronics perform better in various applications, including transistors, batteries, and displays. In addition, flexible electronics have gained much interest in human-machine interaction and wireless sensing. This review briefly examines the origins and fabrication of paper electronics and then moves on to applications and exciting possible paths for paper-based electronics.

Electrochemical Aptasensor Developed Using Two-Electrode Setup and Three-Electrode Setup: Comprising Their Current Range in Context of Dengue Virus Determination.

We present, for the very first time, the fabrication and electrochemical characterization of a paper-based experimental platform for dengue virus analysis. The paper-based device incorporates a screen-printing technology with the help of black carbon conductive ink. The paper-based device utilizes two styles of electrode setups, i.e., the two-electrode system and three-electrode system, and both setups effectively detected the dengue virus with an LOD of 0.1 µg/mL; however, these paper electrodes exhibit various current ranges, and the created sensor was encompassed and compared in this research based on current response. It is observed that the three-electrode system has a substantially higher current range, ranging from 55.53 µA to 322.21 µA, as compared to the two-electrode system, which has a current range of 0.85 µA to 4.54 µA. According to this study, the three-electrode system displayed a good range of current amplification that is roughly 50 times higher than the two-electrode system, which had a weak current response. As a result, the three-electrode method has emerged as a viable option for the very sensitive detection of the dengue virus, as well as for the diagnosis of other diseases.

Borderline microscopic organism and lockdown impacted across the borders-global shakers.

Viruses are the potential cause of several diseases including novel corona virus-19, flu, small pox, chicken pox, acquired immunodeficiency syndrome, severe acute respiratory syndrome etc. The objectives of this review article are to summarize the reasons behind the epidemics caused by several emerging viruses and bacteria, how to control the infection and preventive strategies. We have explained the causes of epidemics along with their preventive measures, the impact of lockdown on the health of people and the economy of a country. Several reports have revealed the transmission of infection during epidemic from the contact of an infected person to the public that can be prevented by implementing the lockdown by the government of a country. Though lockdown has been considered as one of the significant parameters to control the diseases, however, it has some negative consequences on the health of people as they can be more prone to other ailments like obesity, diabetes, cardiac problems etc. and drastic decline in the economy of a country. Therefore, the transmission of diseases can be prevented by warning the people about the severity of diseases, avoiding their public transportation, keeping themselves isolated, strictly following the guidelines of lockdown and encouraging regular exercise.

Analytical techniques for the detection of glycated haemoglobin underlining the sensors.

The increase in concentrations of blood glucose results arise in the proportion of glycated haemoglobin. Therefore, the percentage of glycated haemoglobin in the blood could function as a biomarker for the average glucose level over the past three months and can be used to detect diabetes. The study of glycated haemoglobin tends to be complex as there are about three hundred distinct assay techniques available for evaluating glycated haemoglobin which contributes to some differences in the recorded values from the similar samples. This review outlines distinct analytical methods that have evolved in the recent past for precise recognition of the glycated - proteins.