ABSTRACT
A rapid and accurate diagnostic modality is essential to prevent the spread of SARS-CoV-2. In this study, we proposed a SARS-CoV-2 detection sensor based on surface-enhanced Raman scattering (SERS) to achieve rapid and ultrasensitive detection. The sensor utilized spike protein deoxyribonucleic acid aptamers with strong affinity as the recognition entity to achieve high specificity. The spherical cocktail aptamers-gold nanoparticles (SCAP) SERS substrate was used as the base and Au nanoparticles modified with the Raman reporter molecule that resonates with the excitation light and spike protein aptamers were used as the SERS nanoprobe. The SCAP substrate and SERS nanoprobes were used to target and capture the SARS-CoV-2 S protein to form a sandwich structure on the Au film substrate, which can generate ultra-strong "hot spots"to achieve ultrasensitive detection. Analysis of SARS-CoV-2 S protein was performed by monitoring changes in SERS peak intensity on a SCAP SERS substrate-based detection platform. This assay detects S protein with a LOD of less than 0.7 fg mL-1 and pseudovirus as low as 0.8 TU mL-1 in about 12 min. The results of the simulated oropharyngeal swab system in this study indicated the possibility of it being used for clinical detection, providing a potential option for rapid and accurate diagnosis and more effective control of SARS-CoV-2 transmission. © 2023 Author(s).
ABSTRACT
In the current situation of the global coronavirus disease 2019 (COVID-19) pandemic, there is a worldwide demand for the protection of regular handling surfaces from viral transmission to restrict the spread of COVID-19 infection. To tackle this challenge, researchers and scientists are continuously working on novel antiviral nanocoatings to make various substrates capable of arresting the spread of such pathogens. These nanocoatings systems include metal/metal oxide nanoparticles, electrospun antiviral polymer nanofibers, antiviral polymer nanoparticles, graphene family nanomaterials, and etched nanostructures. The antiviral mechanism of these systems involves depletion of the spike glycoprotein that anchors to surfaces by the nanocoating and makes the spike glycoprotein and viral nucleotides inactive;however, the nature of the interaction between the spike proteins and virus depends on the type of nanostructure and a surface charge over the coating surface. In this article, the current scenario of COVID-19 and how it can be tackled using antiviral nanocoatings from the further transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), along with their different mode of action, are discussed. Additionally, it is also highlighted different types of nanocoatings developed for various substrates to encounter transmission of SARS-CoV-2, future research areas along with the current challenges related to it, and how these challenges can be resolved. © 2022 Wiley-VCH GmbH.
ABSTRACT
The rapid transmission of contagious viruses responsible for global pandemic and various extraordinary risk to precious human life including death. For instance, the current ongoing worldwide COVID-19 pandemic caused by novel coronavirus (SARS-CoV-2) is a communicable disease which is transmitted via touching the contaminated surfaces and then nosocomial route. In absence of effective vaccines and therapies, antiviral coatings are essential in order to prevent or slowdown rapid transmission of viruses. In this prospective, sustainable nanotechnology and material engineering have provided substantial contribution in development of engineered nanomaterial based antiviral coated surfaces to the humanity. In the recent past, nanomaterials based on silver (Ag), titanium oxide (TiO2), copper sulfide (CuS) and copper oxide (CuO) have been modified in the form of engineered nanomaterials with effective antiviral efficacy against SARS-CoV-2. In this review, various recent fundamental aspects for fabrication of metallic nanoparticles (Ag, Ti, Cu etc.) based coated surfaces on various substrates and their antiviral efficacy to inhibit viral transmission of SARS-CoV-2 are discussed along with their respective conceptual mechanisms. The antiviral mechanism based on chemistry of engineered nanomaterials is the key outcome of this review that would be useful for future research in designing and development of more advance antiviral materials and coated surfaces in order to control of future epidemics. © 2022 Elsevier B.V.
ABSTRACT
Nanostructured surfaces enhance ion yields in matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS). The spike protein complex, S1, is one fingerprint signature of Sars-CoV-2 with a mass of 75 kDa. Here, we show that MALDI-MS yields of Sars-CoV-2 spike protein ions in the 100 kDa range are enhanced 50-fold when the matrix-analyte solution is placed on substrates that are coated with a dense forest of multi-walled carbon nanotubes, compared to yields from uncoated substrates. Nanostructured substrates can support the development of mass spectrometry techniques for sensitive pathogen detection and environmental monitoring. © 2023 Author(s).
ABSTRACT
Aquaculture is regarded as one of the fastest methods for preparing food and may be relied upon more and more in the future. Production can be seeded from fish caught in the wild and can be maintained with imported fish food however, aquaculture output and quality is limited by cost and resources, and there is an incentive to make it more environmentally sustainable. If these goals can be achieved, we will produce better quality fish and in higher volumes. Microbial protein feed (MPF) offers a sustainable feedstuff solution for the aquaculture industry in China, with the net benefits of taking less time to prepare, using less water and land, being recyclable and also reducing carbon emissions. MPF provides stable and high quality proteins and is produced through the fermentation of microorganisms by utilizing agricultural and industrial waste as substrates and been extensively used in fish and shrimp production in China. This review describes the microorganisms, raw materials, fermentation processes and nutritional components used in MPF production in aquaculture. We shall discuss also MPF large-scale production processes in detail and then finally, what opportunities and challenges are faced by MPF in Chinese aquaculture in the context of "double carbon"targets and Covid-19. High-efficiency biosynthesis technology using mono-carbon gases to produce protein will become an important field in the future, as it shall facilitate sustainable and healthy feedstocks for the aquaculture industry, and allow China to achieve the goal of lower carbon emissions. © 2023 Elsevier Ltd.
ABSTRACT
The hormone hepcidin present in saliva is a hyperinflammation markers for COVID-19 and other pathological states. Here we present DFT-based vibrational calculations that enabled assign the experimental vibrational spectra of hepcidin and predict its SERS-activiy. © Optica Publishing Group 2022 The Authors.
ABSTRACT
Antiviral compounds are important for generating sterile surfaces. Here, two extremely short peptides, DOPA-Phe-NH2 and DOPA-Phe(4F)-NH2 that can self-assemble into spherical nanoparticles with antiviral activity are presented. The peptide assemblies possess excellent antiviral activity against bacteriophage T4 with antiviral minimal inhibitory concentrations of 125 and 62.5 µg mL−1, for DOPA-Phe-NH2 and DOPA-Phe(4F)-NH2, respectively. When the peptide assemblies are applied on a glass substrate by drop-casting, they deactivate more than 99.9% of bacteriophage T4 and Canine coronavirus. Importantly, the peptide assemblies have low toxicity toward mammalian cells. Overall, the findings can provide a novel strategy for the design and development of antiviral coatings for a decreased risk of viral infections. © 2023 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.
ABSTRACT
Non-metallic materials have emerged as a new family of active substrates for surface-enhanced Raman scattering (SERS), with unique advantages over their metal counterparts. However, owing to their inefficient interaction with the incident wavelength, the Raman enhancement achieved with non-metallic materials is considerably lower with respect to the metallic ones. Herein, we propose colourful semiconductor-based SERS substrates for the first time by utilizing a Fabry-Pérot cavity, which realize a large freedom in manipulating light. Owing to the delicate adjustment of the absorption in terms of both frequency and intensity, resonant absorption can be achieved with a variety of non-metal SERS substrates, with the sensitivity further enhanced by ≈100â times. As a typical example, by introducing a Fabry-Pérot-type substrate fabricated with SiO2 /Si, a rather low detection limit of 10-16 â M for the SARS-CoV-2S protein is achieved on SnS2 . This study provides a realistic strategy for increasing SERS sensitivity when semiconductors are employed as SERS substrates.
ABSTRACT
Non-metallic materials have emerged as a new family of active substrates for surface-enhanced Raman scattering (SERS), with unique advantages over their metal counterparts. However, owing to their inefficient interaction with the incident wavelength, the Raman enhancement achieved with non-metallic materials is considerably lower with respect to the metallic ones. Herein, we propose colourful semiconductor-based SERS substrates for the first time by utilizing a Fabry-Pérot cavity, which realize a large freedom in manipulating light. Owing to the delicate adjustment of the absorption in terms of both frequency and intensity, resonant absorption can be achieved with a variety of non-metal SERS substrates, with the sensitivity further enhanced by ≈100â times. As a typical example, by introducing a Fabry-Pérot-type substrate fabricated with SiO2 /Si, a rather low detection limit of 10-16 â M for the SARS-CoV-2S protein is achieved on SnS2 . This study provides a realistic strategy for increasing SERS sensitivity when semiconductors are employed as SERS substrates.
ABSTRACT
OBJECTIVES: Therapy failure caused by complex population-drug-drug (PDDI) interactions including CYP3A4 can be predicted using mechanistic physiologically-based pharmacokinetic (PBPK) modeling. A synergy between ritonavir-boosted lopinavir (LPVr), ivermectin, and chloroquine was suggested to improve COVID-19 treatment. This work aimed to study the PDDI of the two CYP3A4 substrates (ivermectin and chloroquine) with LPVr in mild-to-moderate COVID-19 adults, geriatrics, and pregnancy populations. METHODS: The PDDI of LPVr with ivermectin or chloroquine was investigated. Pearson's correlations between plasma, saliva, and lung interstitial fluid (ISF) levels were evaluated. Target site (lung epithelial lining fluid (ELF)) levels of ivermectin and chloroquine were estimated. RESULTS: Upon LPVr coadministration, while the chloroquine plasma levels were reduced by 30, 40, and 20%, the ivermectin plasma levels were increased by a minimum of 425, 234, and 453% in adults, geriatrics, and pregnancy populations, respectively. The established correlation equations can be useful in therapeutic drug monitoring (TDM) and dosing regimen optimization. CONCLUSIONS: Neither chloroquine nor ivermectin reached therapeutic ELF levels in the presence of LPVr despite reaching toxic ivermectin plasma levels. PBPK modeling, guided with TDM in saliva, can be advantageous to evaluate the probability of reaching therapeutic ELF levels in the presence of PDDI, especially in home-treated patients.