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1.
Carbohydr Polym ; 280: 119006, 2022 Mar 15.
Article in English | MEDLINE | ID: covidwho-1588175

ABSTRACT

Caulerpa lentillifera (Bryopsidophyceae, Chlorophyta) is an edible seaweed attracting great attention for its expansion of farming scale and increasing consumption in these years. In the present study, a sulfated polysaccharide (CLSP-2) was isolated and separated from C. lentillifera, and its chemical structure was elucidated by a series of chemical and spectroscopic methods. Among these methods, mild acid hydrolysis and photocatalytic degradation were applied to release mono- and oligo-saccharide fragments which were further identified by HPLC-MSn analysis, affording the information of the sugar sequences and the sulfate substitution in CLSP-2. Results indicated that the backbone of CLSP-2 was constructed of →6)-ß-Manp-(1→ with sulfated branches at C2, which were comprised of prevalent →3)-ß-Galp4S-(1→, →3)-ß-Galp2,4S-(1→, and minor Xyl. In addition, the virus neutralization assay revealed that CLSP-2 could effectively protect HeLa cells against SARS-CoV-2 infection with an IC50 of 48.48 µg/mL. Hence, the present study suggests CLSP-2 as a promising agent against SARS-CoV-2.


Subject(s)
COVID-19/virology , Caulerpa/chemistry , Polysaccharides/chemistry , Polysaccharides/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Chromatography, High Pressure Liquid/methods , HeLa Cells , Humans , Hydrolysis , Magnetic Resonance Spectroscopy/methods , Mass Spectrometry/methods , Molecular Weight , Polysaccharides/analysis , SARS-CoV-2 , Seaweed/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Sulfates/chemistry
2.
Theranostics ; 11(14): 7005-7017, 2021.
Article in English | MEDLINE | ID: covidwho-1524524

ABSTRACT

The tumor suppressor protein p53 remains in a wild type but inactive form in ~50% of all human cancers. Thus, activating it becomes an attractive approach for targeted cancer therapies. In this regard, our lab has previously discovered a small molecule, Inauhzin (INZ), as a potent p53 activator with no genotoxicity. Method: To improve its efficacy and bioavailability, here we employed nanoparticle encapsulation, making INZ-C, an analog of INZ, to nanoparticle-encapsulated INZ-C (n-INZ-C). Results: This approach significantly improved p53 activation and inhibition of lung and colorectal cancer cell growth by n-INZ-C in vitro and in vivo while it displayed a minimal effect on normal human Wi38 and mouse MEF cells. The improved activity was further corroborated with the enhanced cellular uptake observed in cancer cells and minimal cellular uptake observed in normal cells. In vivo pharmacokinetic evaluation of these nanoparticles showed that the nanoparticle encapsulation prolongates the half-life of INZ-C from 2.5 h to 5 h in mice. Conclusions: These results demonstrate that we have established a nanoparticle system that could enhance the bioavailability and efficacy of INZ-C as a potential anti-cancer therapeutic.


Subject(s)
Antineoplastic Agents/pharmacology , Colorectal Neoplasms/drug therapy , Indoles/pharmacology , Lung Neoplasms/drug therapy , Nanoparticles/chemistry , Phenothiazines/pharmacology , Tumor Suppressor Protein p53/metabolism , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Biological Availability , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Humans , Indoles/chemistry , Indoles/pharmacokinetics , Indoles/therapeutic use , Mice , Mice, Inbred C57BL , Microscopy, Electron, Transmission , Nanoparticles/toxicity , Nanoparticles/ultrastructure , Phenothiazines/chemistry , Phenothiazines/pharmacokinetics , Phenothiazines/therapeutic use , Spectroscopy, Fourier Transform Infrared , Tumor Suppressor Protein p53/genetics , Xenograft Model Antitumor Assays
3.
Environ Pollut ; 292(Pt A): 118299, 2022 Jan 01.
Article in English | MEDLINE | ID: covidwho-1525784

ABSTRACT

Microplastics (MPs) have been reported in the outdoor/indoor air of urban centres, raising health concerns due to the potential for human exposure. Since aerosols are considered one of the routes of Coronavirus disease 2019 (COVID-19) transmission and may bind to the surface of airborne MPs, we hypothesize that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be associated with the levels of MPs in the air. Our goal was to quantify the SARS-CoV-2 RNA and MPs present in the total suspended particles (TSP) collected in the area surrounding the largest medical centre in Latin America and to elucidate a possible association among weather variables, MPs, and SARS-CoV-2 in the air. TSP were sampled from three outdoor locations in the areas surrounding a medical centre. MPs were quantified and measured under a fluorescence microscope, and their polymeric composition was characterized by Fourier transform infrared (FT-IR) microspectroscopy coupled with attenuated total reflectance (ATR). The viral load of SARS-CoV-2 was quantified by an in-house real-time PCR assay. A generalized linear model (GzLM) was employed to evaluate the effect of the SARS-CoV-2 quantification on MPs and weather variables. TSP samples tested positive for SARS-CoV-2 in 22 out of 38 samples at the three sites. Polyester was the most frequent polymer (80%) found in the samples. The total amount of MPs was positively associated with the quantification of SARS-CoV-2 envelope genes and negatively associated with weather variables (temperature and relative humidity). Our findings show that SARS-CoV-2 aerosols may bind to TSP, such as MPs, and facilitate virus entry into the human body.


Subject(s)
COVID-19 , SARS-CoV-2 , Aerosols , Humans , Latin America , Microplastics , Plastics , RNA, Viral , Spectroscopy, Fourier Transform Infrared
4.
Anal Chim Acta ; 1188: 339207, 2021 Dec 15.
Article in English | MEDLINE | ID: covidwho-1487555

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, also known as 2019-nCov or COVID-19) outbreak has become a huge public health issue due to its rapid transmission making it a global pandemic. Here, we report fabricated fluorine doped tin oxide (FTO) electrodes/gold nanoparticles (AuNPs) complex coupled with in-house developed SARS-CoV-2 spike S1 antibody (SARS-CoV-2 Ab) to measure the response with Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV). The biophysical characterisation of FTO/AuNPs/SARS-CoV-2Ab was done via UV-Visible spectroscopy, Dynamic Light Scattering (DLS), and Fourier Transform Infrared Spectroscopy (FT-IR). The fabricated FTO/AuNPs/SARS-CoV-2Ab immunosensor was optimised for response time, antibody concentration, temperature, and pH. Under optimum conditions, the FTO/AuNPs/Ab based immunosensor displayed high sensitivity with limit of detection (LOD) up to 0.63 fM in standard buffer and 120 fM in spiked saliva samples for detection of SARS-CoV-2 spike S1 antigen (Ag) with negligible cross reactivity Middle East Respiratory Syndrome (MERS) spike protein. The proposed FTO/AuNPs/SARS-CoV-2Ab based biosensor proved to be stable for up to 4 weeks and can be used as an alternative non-invasive diagnostic tool for the rapid, specific and sensitive detection of SARS-CoV-2 Spike Ag traces in clinical samples.


Subject(s)
Biosensing Techniques , COVID-19 , Metal Nanoparticles , Spike Glycoprotein, Coronavirus/analysis , Electrodes , Fluorine , Gold , Humans , Immunoassay , SARS-CoV-2 , Spectroscopy, Fourier Transform Infrared , Tin Compounds
6.
Sci Rep ; 11(1): 20877, 2021 10 22.
Article in English | MEDLINE | ID: covidwho-1479811

ABSTRACT

Adenovirus vectors offer a platform technology for vaccine development. The value of the platform has been proven during the COVID-19 pandemic. Although good stability at 2-8 °C is an advantage of the platform, non-cold-chain distribution would have substantial advantages, in particular in low-income countries. We have previously reported a novel, potentially less expensive thermostabilisation approach using a combination of simple sugars and glass micro-fibrous matrix, achieving excellent recovery of adenovirus-vectored vaccines after storage at temperatures as high as 45 °C. This matrix is, however, prone to fragmentation and so not suitable for clinical translation. Here, we report an investigation of alternative fibrous matrices which might be suitable for clinical use. A number of commercially-available matrices permitted good protein recovery, quality of sugar glass and moisture content of the dried product but did not achieve the thermostabilisation performance of the original glass fibre matrix. We therefore further investigated physical and chemical characteristics of the glass fibre matrix and its components, finding that the polyvinyl alcohol present in the glass fibre matrix assists vaccine stability. This finding enabled us to identify a potentially biocompatible matrix with encouraging performance. We discuss remaining challenges for transfer of the technology into clinical use, including reliability of process performance.


Subject(s)
Adenoviridae/genetics , Adenovirus Vaccines/chemistry , COVID-19 Vaccines/therapeutic use , COVID-19/prevention & control , Vaccine Potency , Adenoviruses, Simian , Biocompatible Materials , Calorimetry, Differential Scanning , Glass , HEK293 Cells , Humans , Light , Magnetic Resonance Spectroscopy , Materials Testing , Microscopy, Confocal , Microscopy, Electron, Scanning , Polyvinyl Alcohol , Rabies Vaccines , Scattering, Radiation , Spectroscopy, Fourier Transform Infrared , Sugars/chemistry , Temperature , Thermogravimetry , Trehalose/chemistry
7.
Sci Rep ; 11(1): 19980, 2021 10 07.
Article in English | MEDLINE | ID: covidwho-1462034

ABSTRACT

The coronavirus disease 2019 (COVID-19) is the latest biological hazard for the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Even though numerous diagnostic tests for SARS-CoV-2 have been proposed, new diagnosis strategies are being developed, looking for less expensive methods to be used as screening. This study aimed to establish salivary vibrational modes analyzed by attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy to detect COVID-19 biological fingerprints that allow the discrimination between COVID-19 and healthy patients. Clinical dates, laboratories, and saliva samples of COVID-19 patients (N = 255) and healthy persons (N = 1209) were obtained and analyzed through ATR-FTIR spectroscopy. Then, a multivariate linear regression model (MLRM) was developed. The COVID-19 patients showed low SaO2, cough, dyspnea, headache, and fever principally. C-reactive protein, lactate dehydrogenase, fibrinogen, D-dimer, and ferritin were the most important altered laboratory blood tests, which were increased. In addition, changes in amide I and immunoglobulin regions were evidenced in the FTIR spectra analysis, and the MLRM showed clear discrimination between both groups. Specific salivary vibrational modes employing ATR-FTIR spectroscopy were established; moreover, the COVID-19 biological fingerprint in saliva was characterized, allowing the COVID-19 detection using an MLRM, which could be helpful for the development of new diagnostic devices.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Saliva/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Adult , Aged , Female , Humans , Immunoglobulins/analysis , Male , Middle Aged , Oxygen/analysis , SARS-CoV-2/isolation & purification
8.
Sci Rep ; 11(1): 15409, 2021 10 11.
Article in English | MEDLINE | ID: covidwho-1462018

ABSTRACT

Early diagnosis of COVID-19 in suspected patients is essential for contagion control and damage reduction strategies. We investigated the applicability of attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy associated with machine learning in oropharyngeal swab suspension fluid to predict COVID-19 positive samples. The study included samples of 243 patients from two Brazilian States. Samples were transported by using different viral transport mediums (liquid 1 or 2). Clinical COVID-19 diagnosis was performed by the RT-PCR. We built a classification model based on partial least squares (PLS) associated with cosine k-nearest neighbours (KNN). Our analysis led to 84% and 87% sensitivity, 66% and 64% specificity, and 76.9% and 78.4% accuracy for samples of liquids 1 and 2, respectively. Based on this proof-of-concept study, we believe this method could offer a simple, label-free, cost-effective solution for high-throughput screening of suspect patients for COVID-19 in health care centres and emergency departments.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Spectroscopy, Fourier Transform Infrared/methods , Adult , Aged , Brazil/epidemiology , COVID-19/epidemiology , Early Diagnosis , Female , Humans , Least-Squares Analysis , Machine Learning , Male , Middle Aged , Time Factors
9.
Sci Rep ; 11(1): 16740, 2021 08 18.
Article in English | MEDLINE | ID: covidwho-1364601

ABSTRACT

The coronavirus pandemic, which appeared in Wuhan, China, in December 2019, rapidly spread all over the world in only a few weeks. Faster testing techniques requiring less resources are key in managing the pandemic, either to enable larger scale testing or even just provide developing countries with limited resources, particularly in Africa, means to perform tests to manage the crisis. Here, we report an unprecedented, rapid, reagent-free and easy-to-use screening spectroscopic method for the detection of SARS-CoV-2 on RNA extracts. This method, validated on clinical samples collected from 280 patients with quantitative predictive scores on both positive and negative samples, is based on a multivariate analysis of FTIR spectra of RNA extracts. This technique, in agreement with RT-PCR, achieves 97.8% accuracy, 97% sensitivity and 98.3% specificity while reducing the testing time post RNA extraction from hours to minutes. Furthermore, this technique can be used in several laboratories with limited resources.


Subject(s)
COVID-19 Testing/methods , RNA, Viral/analysis , Spectroscopy, Fourier Transform Infrared , Humans , RNA, Viral/chemistry , RNA, Viral/isolation & purification , Time Factors
10.
Water Sci Technol ; 84(3): 763-776, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1323037

ABSTRACT

The objective of this work was to evaluate the photocatalytic activity of zinc oxide catalysts supported on natural zeolite clinoptilolite for photocatalytic degradation of the drug hydroxychloroquine, used in the treatment of malaria and which has been tested in the treatment of COVID-19. To synthesize 10%ZnOCP and 15%ZnOCP catalysts, the wet impregnation methodology was used. The raw and synthesized catalysts were characterized by XRD, SEM, XRF, BET, DRS, PCZ, FT-IR and PL. The degradation of hydroxychloroquine was calculated using UV-vis absorption from the samples before and after the photocatalytic process. The maximum percentage of degradation (96%) was obtained with the operational parameters of C0 = 10 mg L-1; Ccat = 2 g L-1 of 15%ZnOCP; pH = 7.5; UV-A radiation. Ecotoxicological tests against the bioindicators Lactuca sativa and Artemia salina confirmed the reduction of effluent toxicity after treatment.


Subject(s)
COVID-19 , Zeolites , Zinc Oxide , COVID-19/drug therapy , Catalysis , Humans , Hydroxychloroquine , SARS-CoV-2 , Spectroscopy, Fourier Transform Infrared
11.
Anal Chem ; 93(30): 10391-10396, 2021 08 03.
Article in English | MEDLINE | ID: covidwho-1316694

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic continues to ravage the world, with many hospitals overwhelmed by the large number of patients presenting during major outbreaks. A rapid triage for COVID-19 patient requiring hospitalization and intensive care is urgently needed. Age and comorbidities have been associated with a higher risk of severe COVID-19 but are not sufficient to triage patients. Here, we investigated the potential of attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy as a rapid blood test for classification of COVID-19 disease severity using a cohort of 160 COVID-19 patients. A simple plasma processing and ATR-FTIR data acquisition procedure was established using 75% ethanol for viral inactivation. Next, partial least-squares-discriminant analysis (PLS-DA) models were developed and tested using data from 130 and 30 patients, respectively. Addition of the ATR-FTIR spectra to the clinical parameters (age, sex, diabetes mellitus, and hypertension) increased the area under the ROC curve (C-statistics) for both the training and test data sets, from 69.3% (95% CI 59.8-78.9%) to 85.7% (78.6-92.8%) and 77.8% (61.3-94.4%) to 85.1% (71.3-98.8%), respectively. The independent test set achieved 69.2% specificity (42.4-87.3%) and 94.1% sensitivity (73.0-99.0%). Diabetes mellitus was the strongest predictor in the model, followed by FTIR regions 1020-1090 and 1588-1592 cm-1. In summary, this study demonstrates the potential of ATR-FTIR spectroscopy as a rapid, low-cost COVID-19 severity triage tool to facilitate COVID-19 patient management during an outbreak.


Subject(s)
COVID-19 , Ataxia Telangiectasia Mutated Proteins , Discriminant Analysis , Humans , Least-Squares Analysis , SARS-CoV-2 , Spectroscopy, Fourier Transform Infrared
12.
Int J Mol Sci ; 22(13)2021 Jul 01.
Article in English | MEDLINE | ID: covidwho-1304670

ABSTRACT

Silk fibroin (SF) has attracted much attention due to its high, tunable mechanical strength and excellent biocompatibility. Imparting the ability to respond to external stimuli can further enhance its scope of application. In order to imbue stimuli-responsive behavior in silk fibroin, we propose a new conjugated material, namely cationic SF (CSF) obtained by chemical modification of silk fibroin with ε-Poly-(L-lysine) (ε-PLL). This pH-responsive CSF hydrogel was prepared by enzymatic crosslinking using horseradish peroxidase and H2O2. Zeta potential measurements and SDS-PAGE gel electrophoresis show successful synthesis, with an increase in isoelectric point from 4.1 to 8.6. Fourier transform infrared (FTIR) and X-ray diffraction (XRD) results show that the modification does not affect the crystalline structure of SF. Most importantly, the synthesized CSF hydrogel has an excellent pH response. At 10 wt.% ε-PLL, a significant change in swelling with pH is observed. We further demonstrate that the hydrogel can be glucose-responsive by the addition of glucose oxidase (GOx). At high glucose concentration (400 mg/dL), the swelling of CSF/GOx hydrogel is as high as 345 ± 16%, while swelling in 200 mg/dL, 100 mg/dL and 0 mg/dL glucose solutions is 237 ± 12%, 163 ± 12% and 98 ± 15%, respectively. This shows the responsive swelling of CSF/GOx hydrogels to glucose, thus providing sufficient conditions for rapid drug release. Together with the versatility and biological properties of fibroin, such stimuli-responsive silk hydrogels have great potential in intelligent drug delivery, as soft matter substrates for enzymatic reactions and in other biomedical applications.


Subject(s)
Drug Delivery Systems/methods , Fibroins/chemistry , Glucose/metabolism , Hydrogels/chemical synthesis , Biocompatible Materials/chemistry , Drug Liberation , Fibroins/metabolism , Glucose/chemistry , Horseradish Peroxidase/chemistry , Hydrogen Peroxide/chemistry , Hydrogen-Ion Concentration , Polylysine/chemistry , Silk/chemistry , Spectroscopy, Fourier Transform Infrared/methods , X-Ray Diffraction
13.
Molecules ; 26(12)2021 Jun 10.
Article in English | MEDLINE | ID: covidwho-1282534

ABSTRACT

Multi-drug resistant pathogens are a rising danger for the future of mankind. Iodine (I2) is a centuries-old microbicide, but leads to skin discoloration, irritation, and uncontrolled iodine release. Plants rich in phytochemicals have a long history in basic health care. Aloe Vera Barbadensis Miller (AV) and Salvia officinalis L. (Sage) are effectively utilized against different ailments. Previously, we investigated the antimicrobial activities of smart triiodides and iodinated AV hybrids. In this work, we combined iodine with Sage extracts and pure AV gel with polyvinylpyrrolidone (PVP) as an encapsulating and stabilizing agent. Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible spectroscopy (UV-Vis), Surface-Enhanced Raman Spectroscopy (SERS), microstructural analysis by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-Ray-Diffraction (XRD) analysis verified the composition of AV-PVP-Sage-I2. Antimicrobial properties were investigated by disc diffusion method against 10 reference microbial strains in comparison to gentamicin and nystatin. We impregnated surgical sutures with our biohybrid and tested their inhibitory effects. AV-PVP-Sage-I2 showed excellent to intermediate antimicrobial activity in discs and sutures. The iodine within the polymeric biomaterial AV-PVP-Sage-I2 and the synergistic action of the two plant extracts enhanced the microbial inhibition. Our compound has potential for use as an antifungal agent, disinfectant and coating material on sutures to prevent surgical site infections.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Aloe/chemistry , Antifungal Agents/chemistry , Gentamicins/chemistry , Microbial Sensitivity Tests , Microscopy, Electron, Scanning/methods , Nystatin/chemistry , Plant Extracts/chemistry , Povidone/chemistry , Salvia/chemistry , Salvia officinalis/chemistry , Spectrometry, X-Ray Emission/methods , Spectroscopy, Fourier Transform Infrared/methods , X-Ray Diffraction/methods
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120006, 2021 Nov 15.
Article in English | MEDLINE | ID: covidwho-1243222

ABSTRACT

Investigation the molecular structure of the system requires a detailed experience in dealing with theoretical computational guides to highlight its important role. Molecular structure of three heterocyclic compounds 8,10-diphenylpyrido[3,2-e][1,2,4]triazolo[4,3-c]pyrimidine-3(2H)-thione (HL), 8-phenyl-10-(p-tolyl)pyrido[3,2-e][1,2,4]triazolo[4,3-c]pyrimidine-3(2H)-thione (CH3L) and10-(4-nitrophenyl)-8-phenylpyrido[3,2-e][1,2,4]triazolo[4,3-c]pyrimidine-3(2H)-thione (NO2L) was studied at DFT/B3LYP/6-31G (d,p) level in ethanol solvent. Spectroscopic properties such Infrared (IR, 1H NMR and 13C NMR) and ultraviolet-visible (UV-VIS) analyses were computed. Some quantum and reactivity parameters (HOMO energy, LUMO energy, energy gap, ionization potential, electron affinity, chemical potential, global softness, lipophelicity) were studied, also molecular electrostatic potential (MEP) was performed to indicate the reactive nucleophilic and electrophilic sites. The effects of H-, CH3- and NO2- substituents on heterocyclic ligands were studied and it was found that the electron donation sites concerned with hydrogen and methyl substituents over nitro substituent. Topological analysis using reduced density gradient (RDG) was discussed in details. To predict the relevant antiviral activity of the reported heterocyclic compounds, molecular docking simulation was applied to the crystal structure of SARS-Cov-2 viral Mpro enzyme with 6WTT code and PLpro with 7JRN code. The enzymatic viral protein gives an image about the binding affinity between the target protein receptor and the heterocyclic ligands entitled. The hydrogen bonding interactions were evaluated from molecular docking with different strength for each ligand compound to discuss the efficiency of heterocyclic ligands toward viral inhibition.


Subject(s)
COVID-19 , Thiones , Humans , Molecular Docking Simulation , Molecular Structure , Pyrimidines , SARS-CoV-2 , Spectroscopy, Fourier Transform Infrared
15.
Molecules ; 26(9)2021 May 04.
Article in English | MEDLINE | ID: covidwho-1238922

ABSTRACT

Quercetin is a poorly water-soluble flavonoid with many benefits to human health. Besides the natural food resources that may provide Quercetin, the interest in delivery systems that could enhance its bioavailability in the human body has seen growth in recent years. Promising delivery system candidates are represented by Solid Lipid Nanoparticles (SLNs) which are composed of well-tolerated compounds and provide a relatively high encapsulation efficiency and suitable controlled release. In this study, Quercetin-loaded and negatively charged Solid Lipid Nanoparticles were synthesized based on a coacervation method, using stearic acid as a core lipid and Arabic Gum as a stabilizer. Samples were qualitatively characterized by Dynamic light scattering (DLS), Zeta Potential, Surface infrared spectroscopy (FTIR-ATR), and Time of flight secondary ion mass spectrometry (ToF-SIMS). Encapsulation efficiency, drug release, and antioxidant effect against ABTS•+ were evaluated in vitro by UV-VIS spectrophotometry.


Subject(s)
Drug Carriers/chemistry , Lipids/chemistry , Nanoparticles/chemistry , Quercetin/pharmacology , Antioxidants/pharmacology , Delayed-Action Preparations , Dynamic Light Scattering , Particle Size , Spectrometry, Mass, Secondary Ion , Spectroscopy, Fourier Transform Infrared , Static Electricity , Time Factors
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 259: 119907, 2021 Oct 05.
Article in English | MEDLINE | ID: covidwho-1228158

ABSTRACT

In this work novel antiviral compound 4-(Dimethylamino) Pyridinium 3, 5-dichlorosalicylate was synthesized and characterized by UV-vis, FT-IR, FT-Raman, 1H NMR and 13C NMR spectra. Quantum chemical computations were carried out by Density functional theory methods at B3LYP level. Electronic stability of the compound arising from hyper conjugative interactions and charge delocalization is investigated using natural bond orbital analysis. Assignments of vibrational spectra have been carried out with the aid of Normal coordinate analysis following the SQMFF methodology. TD-DFT approach was applied to assign the electronic transition observed in UV visible spectrum measured experimentally. Frontier molecular orbital energy gap affirms the bioactivity of the molecule and NCI analysis gives information about inter and intra non covalent interactions. ESP recognises the nucleophilic and electrophilic regions of molecule and the chemical implication of molecule was explained using ELF, LOL. The reactive sites of the compound were studied from the Fukui function calculations and chemical descriptors define the reactivity of the molecule. Molecular docking done with SARS and MERS proteins endorses the bioactivity of molecule and drug likeness factors were calculated to comprehend the biological assets of DADS.


Subject(s)
Quantum Theory , Spectrum Analysis, Raman , Models, Molecular , Molecular Docking Simulation , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Thermodynamics , Vibration
17.
Biosens Bioelectron ; 185: 113177, 2021 Aug 01.
Article in English | MEDLINE | ID: covidwho-1206999

ABSTRACT

Rapid diagnosis and case isolation are pivotal to controlling the current pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, a label-free DNA capacitive biosensor for the detection of SARS-CoV-2 that demonstrates real-time, low-cost, and high-throughput screening of nucleic acid samples is presented. Our novel biosensor composed of the interdigitated platinum/titanium electrodes on the glass substrate can detect the hybridization of analyte DNA with probe DNA. The hybridization signals of specific DNA sequences were verified through exhaustive physicochemical analytical techniques such as Fourier transform infrared (FT-IR) spectrometry, contact-angle analysis, and capacitance-frequency measurements. For a single-step hybridized reaction, the fabricated kit exhibited significant sensitivity (capacitance change, ΔC = ~2 nF) in detecting the conserved region of the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) gene with high sensitivity of 0.843 nF/nM. In addition to capacitive measurements, this selective detection was confirmed by the fluorescence image and intensity from a SARS-CoV-2 gene labeled with a fluorescent dye. We also demonstrated that the kits are recyclable by surface ozone treatment using UV irradiation. Thus, these kits could potentially be applied to various types of label-free DNA, thereby acting as rapid, cost-effective biosensors for several diseases.


Subject(s)
Biosensing Techniques , COVID-19 , DNA , Humans , Point-of-Care Systems , RNA, Viral , SARS-CoV-2 , Sensitivity and Specificity , Spectroscopy, Fourier Transform Infrared
18.
Environ Sci Pollut Res Int ; 28(34): 47517-47527, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1198487

ABSTRACT

A possible source of microplastics has started to be released into nature because of the single-use face masks that protect us against the spread of COVID-19 and are being thrown onto the streets and into seas and nature. This study aims to estimate the amount of face mask use during the COVID-19 pandemic in Turkey, thereby expressing our concerns about waste management and plastic pollution and calling on appropriate solid waste management policies and governments to take the necessary measures to formulate their strategies at all levels. In this context, the number of masks in an area of 1 km2 in 3 different cities was determined theoretically and experimentally. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) were also used to evaluate plastic polymer characteristics of the single-use face mask. It was determined that the three cities produce roughly 10 tons of face masks in a day. With the increasing use of single-use plastics, the impact of face masks on microplastic pollution is of great concern. Although studies on the recovery of disposable masks continue, the level is insufficient. Therefore, studies to be carried out on technologies that will enable the repeated use of masks are important.


Subject(s)
COVID-19 , Masks , Humans , Pandemics , Plastics , SARS-CoV-2 , Spectroscopy, Fourier Transform Infrared , Turkey
19.
Inorg Chem ; 60(9): 6585-6599, 2021 May 03.
Article in English | MEDLINE | ID: covidwho-1195597

ABSTRACT

Silver vanadate nanorods (ß-AgVO3) with silver nanoparticles (Ag-NPs) decorated on the surface of the rods were synthesized by using simple hydrothermal technique and later anchored onto nitrogen-doped reduced graphene oxide (N-rGO) to make a novel nanocomposite. Experimental analyses were carried out to identify the electronic configuration by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analysis, which revealed monoclinic patterns of the C12/m1 space group with Wulff construction forming beta silver vanadate (ß-AgVO3) crystals with optical density and phase transformations. Ag nucleation showed consistent results with metallic formation and electronic changes occurring in [AgO5] and [AgO3] clusters. Transmission electron microscopy and field-emission scanning electron microscopy with elemental mapping and EDX analysis of the morphology reveals the nanorod structure for ß-AgVO3 with AgNPs on the surface and sheets for N-rGO. Additionally, a novel electrochemical sensor is constructed by using Ag/AgVO3/N-rGO on screen-printed carbon paste electrodes for the detection of antiviral drug levofloxacin (LEV) which is used as a primary antibiotic in controlling COVID-19. Using differential pulse voltammetry, LEV is determined with a low detection limit of 0.00792 nm for a linear range of 0.09-671 µM with an ultrahigh sensitivity of 152.19 µA µM-1 cm-2. Furthermore, modified electrode performance is tested by real-time monitoring using biological and river samples.


Subject(s)
Dielectric Spectroscopy/instrumentation , Dielectric Spectroscopy/methods , Levofloxacin/analysis , Nanocomposites/chemistry , Antiviral Agents/analysis , Antiviral Agents/blood , Antiviral Agents/urine , Carbon/chemistry , Electrodes , Graphite/chemistry , Humans , Levofloxacin/blood , Levofloxacin/urine , Limit of Detection , Metal Nanoparticles/chemistry , Microscopy, Electron, Transmission , Nanotubes/chemistry , Photoelectron Spectroscopy , Silver/chemistry , Silver Compounds/chemistry , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Tablets , Vanadates/chemistry , X-Ray Diffraction
20.
Int J Nanomedicine ; 16: 2689-2702, 2021.
Article in English | MEDLINE | ID: covidwho-1186650

ABSTRACT

Background: The COVID-19 pandemic is requesting highly effective protective personnel equipment, mainly for healthcare professionals. However, the current demand has exceeded the supply chain and, consequently, shortage of essential medical materials, such as surgical masks. Due to these alarming limitations, it is crucial to develop effective means of disinfection, reusing, and thereby applying antimicrobial shielding protection to the clinical supplies. Purpose: Therefore, in this work, we developed a novel, economical, and straightforward approach to promote antimicrobial activity to surgical masks by impregnating silver nanoparticles (AgNPs). Methods: Our strategy consisted of fabricating a new alcohol disinfectant formulation combining special surfactants and AgNPs, which is demonstrated to be extensively effective against a broad number of microbial surrogates of SARS-CoV-2. Results: The present nano-formula reported a superior microbial reduction of 99.999% against a wide number of microorganisms. Furthermore, the enveloped H5N1 virus was wholly inactivated after 15 min of disinfection. Far more attractive, the current method for reusing surgical masks did not show outcomes of detrimental amendments, suggesting that the protocol does not alter the filtration effectiveness. Conclusion: The nano-disinfectant provides a valuable strategy for effective decontamination, reuse, and even antimicrobial promotion to surgical masks for frontline clinical personnel.


Subject(s)
Anti-Infective Agents/pharmacology , Disinfectants/pharmacology , Masks , Metal Nanoparticles/chemistry , Silver/pharmacology , Animals , Anti-Infective Agents/administration & dosage , Anti-Infective Agents/chemistry , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , COVID-19/prevention & control , COVID-19/transmission , Chick Embryo , Disinfectants/administration & dosage , Disinfectants/chemistry , Disinfection/methods , Dynamic Light Scattering , Equipment Reuse , Humans , Influenza A Virus, H5N1 Subtype/drug effects , Masks/virology , Metal Nanoparticles/administration & dosage , Microbial Sensitivity Tests , Silver/chemistry , Spectroscopy, Fourier Transform Infrared , Textiles , X-Ray Diffraction
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