Current molecular diagnostics assays for SARS-CoV-2 and emerging variants.

Since the SARS-CoV-2 virus triggered the beginning of the COVID-19 pandemic, scientists, government officials, and healthcare professionals around the world recognized the need for accessible, affordable, and accurate testing to predict and contain the spread of COVID-19. In the months that followed, research teams designed, tested, and rolled out hundreds of diagnostic assays, each with different sampling methods, diagnostic technologies, and sensitivity levels. However, the contagious virus continued to spread; SARS-CoV-2 travelled through airborne particles and spread rapidly, despite the widening use of diagnostic assays. As the pandemic continued, hundreds of millions of people contracted COVID-19 and millions died worldwide. With so many infections, SARS-CoV-2 received many opportunities to replicate and mutate, and from these mutations emerged more contagious, deadly, and difficult-to-diagnose viral mutants. Each change to the viral genome presented potential added challenges to containing the virus, and as such, researchers have continued developing and improving testing methods to keep up with COVID-19. In this chapter, we examine several SARS-CoV-2 variants that have emerged during the pandemic. Additionally, we discuss a few major COVID-19 diagnostic technique categories, including those involving real-time PCR, serology, CRISPR, and electronic biosensors. Finally, we address SARS-CoV-2 variants and diagnostic assays in the age of COVID-19 vaccines.

Honey-based trap for Pseudomonas: a sustainable prototype for water disinfection.

This paper introduces a novel prototype for the removal of Pseudomonas from water samples. Bacterial cells have the tendency to get attracted towards specific chemicals (chemotaxis); a 'honey-based trap' (henceforth, addressed as 'honey-trap') strip was conceptualized by integrating a combination of serine, pseudomonas-specific chemoattractant and honey to attract and inhibit the bacteria in situ. Honey, a natural antimicrobial agent, has garnered the attention as an effective inhibitor for Pseudomonal biofilms and wound infections. Dipping serine side of the strip attracted bacteria towards honey-trap, whereby the porous nature of the strip facilitated the 'trapping' and subsequent diffusion of the bacterial cells towards honey-adsorbed end of the strip. This 'honey-trap' reportedly leads to the targeted elimination of Pseudomonas, hence facilitating its removal. The percentage efficacy of this 'honey-trap' device is 96% with a log reduction equivalent to 1.6 within a time frame of 2 h. Pseudomonas aeruginosa, although, not a natural contaminant of potable water, enters circulation due to improperly maintained plumbing fixtures and storage facilities. Honey-trap strip is an easy to use, biodegradable and cost-effective sustainable solution, and thus a scaled-up version of this device may enable substantial improvement in quality of potable water. Schematics showing the preparation and working of the Pseudomonas Honey-trap. Serine as an attractant and honey as an inhibitor was absorbed on filter strips (HT) for use. The strip was dipped in culture from serine end. After different time period of incubation, difference in bacterial load was confirmed by measuring the electrical conductivity and OD600nm of the culture. Additionally, inhibitory effect of HS was confirmed by placing the strip incubated with culture on agar plates and differences in bacterial lawn were monitored. Removal of bacterial cells from the suspension was also confirmed using absorption spectroscopy.

Emerging Protein Biomarkers in Epithelial Ovarian Cancer Prognosis: An Aid for Multivariate Indexing.

Epithelial ovarian cancer (EOC) is a chronic and degenerative disease propelled by a mutation in BRCA1/2 genes, familial history, smoking and polycystic ovary syndrome. Although the lifetime risk of ovarian cancer is low, yet it is the fifth leading cause of cancer-related deaths. Surprisingly, EOC represents 90% of all ovarian cancers, out of which 70% of women are diagnosed with the malignancy at its advanced III-IV stages. Early detection may increase the life expectancy up to 5 years. Thus, it has become the need of the hour to attain improvement of clinical outcomes of EOC and improve the life expectancy of patients. A plethora of proteins in different biological fluids may serve as prospective identifiers for the disease. Over the years, accurate identification of proteins secreted by EOC cells has been perfected by in vitro and in silico state-of-theart technologies. Multivariate test, consisting of histo-pathological data in combination with protein biomarker panel has paved way for enhanced and accurate assessment of EOC; still, there is a chance of further improvement. This review encompasses the advances made in ovarian cancer biomarker discovery and demonstrates their potential usefulness for the design of early diagnostics of EOC.

Predicting Diagnostic Potential of Cathepsin in Epithelial Ovarian Cancer: A Design Validated by Computational, Biophysical and Electrochemical Data.

BACKGROUND: Epithelial ovarian cancer remains one of the leading variants of gynecological cancer with a high mortality rate. Feasibility and technical competence for screening and detection of epithelial ovarian cancer remain a major obstacle and the development of point of care diagnostics (POCD) may offer a simple solution for monitoring its progression. Cathepsins have been implicated as biomarkers for cancer progression and metastasis; being a protease, it has an inherent tendency to interact with Cystatin C, a cysteine protease inhibitor. This interaction was assessed for designing a POCD module. METHODS: A combinatorial approach encompassing computational, biophysical and electron-transfer kinetics has been used to assess this protease-inhibitor interaction. RESULTS: Calculations predicted two cathepsin candidates, Cathepsin K and Cathepsin L based on their binding energies and structural alignment and both predictions were confirmed experimentally. Differential pulse voltammetry was used to verify the potency of Cathepsin K and Cathepsin L interaction with Cystatin C and assess the selectivity and sensitivity of their electrochemical interactions. Electrochemical measurements indicated selectivity for both the ligands, but with increasing concentrations, there was a marked difference in the sensitivity of the detection. CONCLUSIONS: This work validated the utility of dry-lab integration in the wet-lab technique to generate leads for the design of electrochemical diagnostics for epithelial ovarian cancer.