Esterase 2 as a fluorescent biosensor for the detection of organophosphorus compounds: docking and electronic insights from molecular dynamics

In silico engineering of graphitic carbon nitride nanostructures through germanium mono-doping and codoping with transition metals (Ni, Pd, Pt) as sensors for diazinon organophosphorus pesticide pollutants

The extensive use of pesticides has raised concerns about environmental contamination, which poses potential health risks to humans and aquatic life. Hence, the need for a healthy and friendly ecosystem initiated this study, which was modeled through profound density functional theory (DFT) at the B3LYP-D3(BJ)/def2svp level of theory to gain insights into the electronic characteristics of germanium-doped graphitic carbon nitride (Ge@C3N4) engineered with nickel group transition metals (Ni, Pt, and Pd) as sensors for diazinon (DZN), an organophosphorus pesticide pollutant. To effectively sense diazinon, this research employed a variety of methodologies, beginning with the analysis of electronic properties, intermolecular investigations, adsorption studies, and sensor mechanisms. These detailed assessments revealed insightful results, as clearly indicated by their narrow energy gap and other electronic properties. Noncovalent interactions characterized by van der Waals forces were revealed predominantly by quantum atoms in molecules (QTAIM) and noncovalent interaction (NCI) analyses. Furthermore, the results of the adsorption studies, which measured the strength of the interaction between the pesticide molecules and the nanostructures, revealed favorable results characterized by negative adsorption energies of - 1.613, - 1.613, and - 1.599 eV for DZN_Ge@C3N4, DZN_Ni_Ge@C3N4, and DZN_Pd_Ge@C3N4, respectively. The simulated mechanism through which diazinon is sensed revealed favorable results, as observed by the negative Fermi energy and fraction of electron transfer (∆N), as well as a high dipole moment. This study also revealed that the codoping influenced the behavior of the systems, revealing that DZN_Ni_Ge@C3N4 was the best sensing system because of its strongest adsorption (- 1.613 eV), highest dipole moment (8.348 D), most negative Fermi energy (- 1.300 eV), lowest work function (1.300 eV), and good ∆N (- 1.558) values. This study, therefore, proposes these nanostructures for further in vitro studies seeking to sense diazinon and other pesticides to maintain healthy ecosystems.

Recent advances in computational methods for biosensor design

Biosensors are analytical tools with a great application in healthcare, food quality control, and environmental monitoring. They are of considerable interest to be designed by using cost-effective and efficient approaches. Designing biosensors with improved functionality or application in new target detection has been converted to a fast-growing field of biomedicine and biotechnology branches. Experimental efforts have led to valuable successes in the field of biosensor design; however, some deficiencies restrict their utilization for this purpose. Computational design of biosensors is introduced as a promising key to eliminate the gap. A set of reliable structure prediction of the biosensor segments, their stability, and accurate descriptors of molecular interactions are required to computationally design biosensors. In this review, we provide a comprehensive insight into the progress of computational methods to guide the design and development of biosensors, including molecular dynamics simulation, quantum mechanics calculations, molecular docking, virtual screening, and a combination of them as the hybrid methodologies. By relying on the recent advances in the computational methods, an opportunity emerged for them to be complementary or an alternative to the experimental methods in the field of biosensor design.

The research of aptamer biosensor technologies for detection of microorganism

The activities and transmissions of microorganisms are closely related to human, and all kinds of diseases caused by pathogenic microorganisms have attracted attention in the world and brought many challenges to human health and public health. The traditional microbial detection technologies have characteristics of longer detection cycle and complicated processes, therefore, which can no longer meet the detection requirements in the field of public health. At present, it is the focus to develop and design a novel, rapid, and simple microbial detection method in the field of public health. Herein, this article summarized the development of aptamer biosensor technologies for detection of microorganism in the aspect of bacteria, viruses, and toxins in detail, including optical aptamer sensors such as fluorometry and colorimetry, electrochemical aptamer sensors, and other technologies combined with aptamer. KEY POINTS: • Aptamer biosensor is a good platform for microbial detection. • Aptamer biosensors include optical sensors and electrochemical sensors. • Aptamer sensors have been widely used in the detection of bacteria, viruses, and other microorganisms.

Enzyme-based optical biosensors for organophosphate class of pesticide detection

A systematic review of enzyme based optical detection schemes for the detection and analysis of organophosphate pesticides has been presented.

Future Therapeutic Perspectives into the Alzheimer's Disease Targeting the Oxidative Stress Hypothesis

Alzheimer's disease (AD) is a neurodegenerative disease that is usually accompanied by aging, increasingly being the most common cause of dementia in the elderly. This disorder is characterized by the accumulation of beta amyloid plaques (Aβ) resulting from impaired amyloid precursor protein (APP) metabolism, together with the formation of neurofibrillary tangles and tau protein hyperphosphorylation. The exacerbated production of reactive oxygen species (ROS) triggers the process called oxidative stress, which increases neuronal cell abnormalities, most often followed by apoptosis, leading to cognitive dysfunction and dementia. In this context, the development of new therapies for the AD treatment is necessary. Antioxidants, for instance, are promising species for prevention and treatment because they are capable of disrupting the radical chain reaction, reducing the production of ROS. These species have also proven to be adjunctive to conventional treatments making them more effective. In this sense, several recently published works have focused their attention on oxidative stress and antioxidant species. Therefore, this review seeks to show the most relevant findings of these studies.