Currently, 47 million people live with dementia globally, and it is estimated to increase more than threefold (~131 million) by 2050. Alzheimer's disease (AD) is one of the major causative factors to ...induce progressive dementia. AD is a neurodegenerative disease, and its pathogenesis has been attributed to extracellular aggregates of amyloid β (Aβ) plaques and intracellular neurofibrillary tangles made of hyperphosphorylated τ-protein in cortical and limbic areas of the human brain. It is characterized by memory loss and progressive neurocognitive dysfunction. The anomalous processing of APP by β-secretases and γ-secretases leads to production of Aβ
and Aβ
monomers, which further oligomerize and aggregate into senile plaques. The disease also intensifies through infectious agents like HIV. Additionally, during disease pathogenesis, the presence of high concentrations of Aβ peptides in central nervous system initiates microglial infiltration. Upon coming into vicinity of Aβ, microglia get activated, endocytose Aβ, and contribute toward their clearance via TREM2 surface receptors, simultaneously triggering innate immunoresponse against the aggregation. In addition to a detailed report on causative factors leading to AD, the present review also discusses the current state of the art in AD therapeutics and diagnostics, including labeling and imaging techniques employed as contrast agents for better visualization and sensing of the plaques. The review also points to an urgent need for nanotechnology as an efficient therapeutic strategy to increase the bioavailability of drugs in the central nervous system.
On global scale, the current situation of pandemic is symptomatic of increased incidences of contagious diseases caused by pathogens. The faster spread of these diseases, in a moderately short ...timeframe, is threatening the overall population wellbeing and conceivably the economy. The inadequacy of conventional diagnostic tools in terms of time consuming and complex laboratory-based diagnosis process is a major challenge to medical care. In present era, the development of point-of-care testing (POCT) is in demand for fast detection of infectious diseases along with “on-site” results that are helpful in timely and early action for better treatment. In addition, POCT devices also play a crucial role in preventing the transmission of infectious diseases by offering real-time testing and lab quality microbial diagnosis within minutes. Timely diagnosis and further treatment optimization facilitate the containment of outbreaks of infectious diseases. Presently, efforts are being made to support such POCT by the technological development in the field of internet of medical things (IoMT). The IoMT offers wireless-based operation and connectivity of POCT devices with health expert and medical centre. In this review, the recently developed POC diagnostics integrated or future possibilities of integration with IoMT are discussed with focus on emerging and re-emerging infectious diseases like malaria, dengue fever, influenza A (H1N1), human papilloma virus (HPV), Ebola virus disease (EVD), Zika virus (ZIKV), and coronavirus (COVID-19). The IoMT-assisted POCT systems are capable enough to fill the gap between bioinformatics generation, big rapid analytics, and clinical validation. An optimized IoMT-assisted POCT will be useful in understanding the diseases progression, treatment decision, and evaluation of efficacy of prescribed therapy.
•Infectious diseases are serious but manageable using intelligent diagnostics.•Biosensing enables low detection of virus needed for viral infection management.•IoMT-integrated biosensor enable diagnostics at site-of-infection efficiently.•IoMT-supported POC-biosensing enable viral infection management in personalized manner.•POC-biosensing is needed for diseases diagnostics and therapy decision along with investigation.
Effective and efficient management of human betacoronavirus severe acute respiratory syndrome (SARS)-CoV-2 virus infection i.e., COVID-19 pandemic, required sensitive and selective sensors with short ...sample-to-result durations for performing desired diagnostics. In this direction, one appropriate alternative approach to detect SARS-CoV-2 virus protein at low level i.e., femtomolar (fM) is exploring plasmonic metasensor technology for COVID-19 diagnostics, which offers exquisite opportunities in advanced healthcare programs, and modern clinical diagnostics. The intrinsic merits of plasmonic metasensors stem from their capability to squeeze electromagnetic fields, simultaneously in frequency, time, and space. However, the detection of low-molecular weight biomolecules at low densities is a typical drawback of conventional metasensors that has recently been addressed using toroidal metasurface technology. This research is focused on the fabrication of a miniaturized plasmonic immunosensor based on toroidal electrodynamics concept that can sustain robustly confined plasmonic modes with ultranarrow lineshapes in the terahertz (THz) frequencies. By exciting toroidal dipole mode using our quasi-infinite metasurface and a judiciously optimized protocol based on functionalized gold nanoparticles (AuNPs) conjugated with the specific monoclonal antibody specific to spike protein (S1) of SARS-CoV-2 virus onto the metasurface, the resonance shifts for diverse concentrations of the spike protein are monitored. Possessing molecular weight around ~76 kDa allowed to detect the presence of SARS-CoV-2 virus protein with significantly low as limit of detection (LoD) was achieved as ~4.2 fM. We envisage that outcomes of this research will pave the way toward the use of toroidal metasensors as practical technologies for rapid and precise screening of SARS‐CoV‐2 virus carriers, symptomatic or asymptomatic, and spike proteins in hospitals, clinics, laboratories, and site of infection.
•Terahertz plasmonic metasensors for the detection of SARS-CoV-2 clinical diagnosis.•Quantitative and qualitative detection of spike proteins.•Rapid and precise detection of SARS-CoV-2 spike proteins at femtomolar concentrations.•Simple detection approach and compatible for high throughput COVID-19 screening in hospitals and test laboratories.•Early-stage detection of the infection through noninvasive tests.
Since the discovery of biosensor, continuous efforts are being made to design and develop novel biosensing systems of reduced form factor and high performance. State-of-art biosensing technology is ...the least component-based and tunable outcome depends on the selection of bio-sensing materials. Among various smart-electro-active nanostructures sensing materials, liquid crystals (LCs) are emerging as a choice of materials to develop efficient biosensor for targeted biomarkers detection. In the modern world of science and technology, LC materials have exhibited significant importance as promising materials in the various display as well as in non-display (optical devices based on LC) applications. Most of the displays currently used and available in the market are based mainly on LC technology. Besides the parent area of electronic displays, advancements have been made to tune the potentials of LC materials properties to develop biosensors of desired performance. Due to easily perturbed by external stimulation and species including bioactive or analytes project LC-based platform suitable for fabricate simple, efficient and cost-effective biosensors. This review article is an effort to describe the advancements in LC and nanotechnology-assisted LC systems for developing an efficient biosensor of tunable performance. The biosensing mechanism associated with nanotechnology-assisted LC-based sensing systems, challenges in the state-of-art technology, and future direction required to develop a LC-based analytical diagnostics tool are also the focus of this report. We believe that this review will serve as a guideline to researchers who aim to fabricate a nanotechnology-assisted LC materials-based biosensor for rapid, cost-effective, selective diagnostics of a targeted disease for health care management.
•Next generation bio-sensing technology demand least component based approach.•Liquid crystals (LC)-based system is highly sensitive and easy to fabricate.•Nanotechnology assisted LC biosensor enables high loading of bio-actives and amplifies signal.•Nano-assisted LC have exhibited improved sensing performance.•Such systems can be promoted as next generation diagnostics tools.
CRISPR-Cas9/gRNA exhibits therapeutic efficacy against latent human immunodeficiency virus (HIV) genome but the delivery of this therapeutic cargo to the brain remains as a challenge. In this ...research, for the first time, we demonstrated magnetically guided non-invasive delivery of a nano-formulation (NF), composed of Cas9/gRNA bound with magneto-electric nanoparticles (MENPs), across the blood-brain barrier (BBB) to inhibit latent HIV-1 infection in microglial (hμglia)/HIV (HC69) cells. An optimized ac-magnetic field of 60 Oe was applied on NF to release Cas9/gRNA from MENPs surface and to facilitate NF cell uptake resulting in intracellular release and inhibition of HIV. The outcomes suggested that developed NF reduced HIV-LTR expression significantly in comparison to unbound Cas9/gRNA in HIV latent hμglia/HIV (HC69) cells. These findings were also validated qualitatively using fluorescence microscopy to assess NF efficacy against latent HIV in the microglia cells. We believe that CNS delivery of NF (CRISPR/Cas9-gRNA-MENPs) across the BBB certainly will have clinical utility as future personalized nanomedicine to manage neuroHIV/AIDS.
Polarizing optical images of the LC test cells filled with 8CB liquid crystal in (a) a homeotropically aligned reference cell coated with DMOAP/APTMS (b) an enzyme cell (c)-(e) biosensing cell at ...various histamine concentrations as 20 mg/L, 100 mg/L and 500 mg/L respectively.
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•A novel liquid crystal (LC) based biosensor to detect histamine level is presented.•The biosensor is based on the orientational transition of nematic LC.•The self-assembled monolayer of surfactant and silane is made.•The dielectric studies were also performed to provide an impact on the sensitivity of biosensor.•The developed LC based histamine biosensor provides sensing at a limit of 20 mg/L–500 mg/L.
The effects of histamine on blood vessels play a key role in immune response at the time of physical damage or some allergic reaction. The prevalent measurement methods for the detection of histamine are amperometric and capacitive biosensor techniques. Here, we present an easy fabrication and optimization studies of a novel liquid crystal (LC) based biosensor capable of detecting histamine level. The proposed biosensor is based on the orientational transition of nematic LC (NLC), 4′-octyl-4-biphenylcarbonitrile by enzymatic reaction of biomolecules. The sensing mechanism is based on homeotropic-to-planar configurational change of long molecular axes of LC when diamine oxidase/histamine was immobilized on the pretreated glass substrate. The developed LC-based histamine biosensor provides a good optical and dielectric response at a detection limit of 20 mg/L–500 mg/L.
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•2D borophene flatland is emerging suitable for high-performance application.•Developing functionalized borophene is suitable for efficient biosensing prototypes.•These systems can be ...translated for POC application.•IoMT and smartphone supported such systems are required for personalized healthcare.
2D-materials-based biosensing, supported by artificial intelligence (AI) and internet-of-medical things (IoMT), has emerged as a new technological platform for intelligent diagnostics at point-of-care (POC). To achieve a desired biosensing, high performance engineering in smart functionalized opto-electric 2D materials is crucial. Recently, borophene has emerged as one of such advanced platforms due to its high electroactive surface, anisotropic behaviour, high electron transport, controlled optical properties, feasibility of deposition in thin films, and possibility to generate surface functionalities. Although ease of fabrication still stands challenging, borophene could be deposited on flexible substrate, functionalized using chemistries to immobilize bio-actives, and control over electro-optical properties to develop a highly sensitive biosensing systems operated by smartphone to achieve early stage POC diagnosis. This letter is an attempt to project borophene for smart bio-sensing.
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