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Monitoring fenitrothion (FNT) residues in food and the environment is crucial due to its high environmental toxicity. In this study, we developed a sensitive, reliable electrochemical method for detecting FNT by using screen-printed carbon electrodes (SPCE) modified with porous graphene oxide (PGO) nanosheets. PGO surface properties have been meticulously characterized using advanced spectroscopic techniques. Electrochemical impedance spectroscopy and cyclic voltammetry were used to test the electrochemical properties of the PGO-modified sensor. The PGO-modified sensor exhibited remarkable sensitivity, achieving a detection limit as low as 0.061 µM and a broad linear range of 0.02-250 µM. Enhanced performance is due to PGO's high surface area and excellent electrocatalytic properties, which greatly improved electron transfer. Square wave voltammetry was used to demonstrate the sensor's efficacy as a real-time, on-site monitoring tool for FNT residues in fruit and water. The outstanding performance of the PGO/SPCE sensor underscores its applicability in ensuring food safety and environmental protection.
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In this study, nanocomposites of AgNPs encapsulated in carboxymethyl chitosan (CMCS) with sulfobetaine methacrylate (SB) hydrogel (AgNPs/CMCS-SB) were synthesized. The UV-Vis spectra indicated the presence of AgNPs, with a broad peak at around 424 nm, while the AgNPs-loaded CMCS-SB nanocomposite exhibited absorption peaks at 445 nm. The size and dispersion of AgNPs varied with the concentration of the AgNO3 solution, affecting swelling rates: 148.37 ± 15.63%, 172.26 ± 18.14%, and 159.17 ± 16.59% for 1.0 mM, 3.0 mM, and 5.0 mM AgNPs/CMCS-SB, respectively. Additionally, water absorption capacity increased with AgNPs content, peaking at 11.04 ± 0.54% for the 3.0 mM AgNPs/CMCS-SB nanocomposite. Silver release from the nanocomposite was influenced by AgNO3 concentration, showing rapid initial release followed by a slower rate over time for the 3.0 mM AgNPs/CMCS-SB. XRD patterns affirmed the presence of AgNPs, showcasing characteristic peaks indicative of a face-centered cubic (fcc) structure. The FTIR spectra highlighted interactions between AgNPs and CMCS-SB, with noticeable shifts in characteristic bands. In addition, SEM and TEM images validated spherical AgNPs within the CMCS-SB hydrogel network, averaging approximately 70 and 30 nm in diameter, respectively. The nanocomposite exhibited significant antibacterial activity against S. aureus and E. coli, with inhibition rates of 98.9 ± 0.21% and 99.2 ± 0.14%, respectively, for the 3.0 mM AgNPs/CMCS-SB nanocomposite. Moreover, cytotoxicity assays showcased the efficacy of AgNPs/CMCS-SB against human colorectal cancer cells (HCT-116 cells), with the strongest cytotoxicity (61.7 ± 4.3%) at 100 µg/mL. These results suggest the synthesized AgNPs/CMCS-SB nanocomposites possess promising attributes for various biomedical applications, including antimicrobial and anticancer activities, positioning them as compelling candidates for further advancement in biomedicine.
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A Schiff-base Ethyl (E)-2-(3-((2-carbamothioylhydrazono)methyl)-4-hydroxyphenyl)-4-methylthiazole-5-carboxylate (TZTS) dual functional colorimetric and photoluminescent chemosensor which includes thiazole and thiosemicarbazide has been synthesized to detect arsenic (As3+) ions selectively in DMSO: H2O (7:3, v/v) solvent system. The molecular structure of the probe was characterized via FT-IR, 1H, and 13C NMR & HRMS analysis. Interestingly, the probe exhibits a remarkable and specific colorimetric and photoluminescence response to As3+ ions when exposed to various metal cations. The absorption spectral changes of TZTS were observed upon the addition of As3+ ions, with a naked eye detectable color change from colorless to yellow color. Additionally, the chemosensor (TZTS) exhibited a new absorption band at 412 nm and emission enhancements in photoluminescence at 528 nm after adding As3+ ions. The limit of detection (LOD) for As3+ ions was calculated to be 16.5 and 7.19 × 10-9 M by the UV-visible and photoluminescent titration methods, respectively. The underlying mechanism and experimental observations have been comprehensively elucidated through techniques such as Job's plot, Benesi-Hildebrand studies, and density functional theory (DFT) calculations. For practical application, the efficient determination of As3+ ions were accomplished using a spike and recovery approach applied to real water samples. In addition, the developed probe was successfully employed in test strip applications, allowing for the naked-eye detection of arsenic ions. Moreover, fluorescence imaging experiments of As3+ ions in the breast cancer cell line (MCF-7) demonstrated their practical applications in biological systems. Consequently, these findings highlight the significant potential of the TZTS sensor for detecting As3+ ions in environmental analysis systems.
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Arsênio , Colorimetria , Teoria da Densidade Funcional , Tiazóis , Colorimetria/métodos , Humanos , Tiazóis/química , Tiazóis/análise , Arsênio/análise , Limite de Detecção , Células MCF-7 , Íons/análise , Imagem ÓpticaRESUMO
Globally, antibiotic resistance is a challenging issue in healthcare sector. The emergence of multiple drug-resistant bacteria has forced us to modify existing medicines and or formulate newer medicines that are effective and inexpensive. In this perspective, this study involves the formation of zinc oxide nanoparticles (ZnO NPs) by utilizing the Lawsonia inermis (Li) leaf extract. The prepared L. inermis leaf extract mediated ZnO NPs (Li-ZnO NPs) were bio-physically characterized. The antibacterial and radical scavenging effects of Li-ZnO NPs were evaluated. In addition, ZnO NPs were conjugated with standard antibiotic (ciprofloxacin) and its drug loading efficiency, drug release and antibacterial efficacy were tested and compared with non-drug loaded ZnO NPs. An absorbance peak at 340 nm was noted for Li-ZnO NPs. After conjugation with the drug, two absorbance peaks- one at 242 nm characteristic of ciprofloxacin and the other at 350 nm characteristics of ZnO NPs were observed. The crystallite size was 18.7 nm as determined by XRD. The antibacterial effect was higher on Gram-positive (S. aureus and S. pyogenes) than the Gram-negative pathogens (E. coli and K. pneumoniae). Inhibition of S. aureus and S. pyogenes biofilm at 100 µg mL-1were, respectively, 97.5 and 92.6%. H2O2 free radicals was inhibited to 90% compared to the standard ascorbic acid at 100 µg mL-1. After drug loading, the FTIR spectrum confirmed the existence of ciprofloxacin peaks at 965 cm-1 and Zn-O bond at 492 cm-1. The drug loading capacity of 15 nm sized ZnO NPs was higher (58, 75, 90 and 95% at 1, 2.5, 5 and 10% drug concentrations, respectively) compared to 20 nm. Similarly, the percentage of drug (ciprofloxacin) released from 15 nm ZnO NPs were increased to 90% at 10% drug-loaded samples, respectively. Also, the antibiotic loaded ZnO NPs had significant antibacterial effects against tested bacteria compared to Li-ZnO NPs and ciprofloxacin alone. This revealed that the antibiotic loaded ZnO NPs offer a sustainable route to treat multi-drug-resistant bacterial infections.
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Antibacterianos , Antioxidantes , Biofilmes , Lawsonia (Planta) , Extratos Vegetais , Folhas de Planta , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Lawsonia (Planta)/química , Folhas de Planta/química , Biofilmes/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Ciprofloxacina/farmacologia , Ciprofloxacina/químicaRESUMO
A newly synthesized Schiff's base 2-(2-([2,2'-bithiophen]-5-ylmethylene)hydrazinyl)benzothiazole (BT) was obtained from the condensation reaction between 2-hydrazinobenzothiazole and 2,2-bithiophene-5-carboxaldehyde. The prepared probe BT was subjected to a confirmation of the structural arrangement through NMR, FTIR, ESI-HRMS, and single-crystal XRD spectral analysis. The BT colorimetric sensor showed selectivity and sensitivity toward the cyanide (CN-) ion over other common anions such as ClO4-, Cl-, Br-, F-, I-, NO2-, OH-, HSO4-, and H2PO4- in a partial aqueous system CH3CN/H2O (8:2, v/v). The probe BT detects CN- with the lowest detection range as low as 1.33 × 10-8 M (3.59 ppm); in comparison to that given by WHO guidelines, it is significantly lower. The stoichiometric interaction between the probe BT and analyte CN- was found to be 1:1 (BT/CN-) binding mode using Jobs plot, and further association binding affinity was calculated to be 6.64 × 10-3 M-1. Additionally, these results were further supported by the FTIR and DFT calculations, as well as the 1H NMR titration analysis, which complemented the binding data. The sensor probe BT was successfully employed in a cotton swab test kit approach and also in smartphone-assisted applications for the determination of CN- ions. Finally, the outstanding sensing properties of probe BT aided the quantitative detection of CN- ions, and it could be further applied to a variety of food samples, including apple seeds, sprouting potatoes, and cassava.
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A facile and convenient protocol for the regioselective construction of functionalized 2-hydroxybenzophenones is described. This protocol involves the Sc(OTf)3/BF3·OEt2-catalyzed benzannulation of 2-vinyloxirans with 3-formylchromone, which involves cascade in situ diene formation, [4 + 2] cycloaddition, elimination, and ring-opening strategies. Moreover, it provides an expedited synthetic pathway to access biologically intriguing 1,4-naphthoquinones and anthraquinones including vitamin K3 and tectoquinone. The synthesized compounds also hold potential for use as UV filters and show promise as chemosensors for Cu2+ and Mg2+ ions.
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Ti3C2-MXene material, known for its strong electronic conductivity and optical properties, has emerged as a promising alternative to noble metals as a cocatalyst for the development of efficient photocatalysts used in environmental cleanup. In this study, we investigated the photodegradation of crystal-violet (CV) dye when exposed to UV light using a newly developed photocatalyst known as Ti3C2-MXene/NiO nanocomposite-decorated CsPbI3 perovskite, which was synthesized through a hydrothermal method. Our research investigation into the structural, morphological, and optical characteristics of the Ti3C2-MXene/NiO/CsPbI3 composite using techniques such as FTIR, XRD, TEM, SEM-EDS mapping, XPS, UV-Vis, and PL spectroscopy. The photocatalytic efficacy of the Ti3C2-MXene/NiO/CsPbI3 composite was assessed by evaluating its ability to degrade CV dye in an aqueous solution under UV-light irradiation. Remarkably, the Ti3C2-MXene/NiO/CsPbI3 composite displayed a significant improvement in both the degradation rate and stability of CV dye when compared to the Ti3C2-MXene/NiO nanocomposite and CsPbI3 perovskite materials. Furthermore, the UV-visible absorption spectrum of the Ti3C2-MXene/NiO/CsPbI3 composite demonstrated a reduced band gap of 2.41 eV, which is lower than that of Ti3C2-MXene/NiO (3.10 eV) and Ti3C2-MXene (1.60 eV). In practical terms, the Ti3C2-MXene/NiO/CsPbI3 composite achieved an impressive 92.8% degradation of CV dye within 90 min of UV light exposure. We also confirmed the significant role of photogenerated holes and radicals in the CV dye removal process through radical scavenger trapping experiments. Based on our findings, we proposed a plausible photocatalytic mechanism for the Ti3C2-MXene/NiO/CsPbI3 composite. This research may open up new avenues for the development of cost-effective and high-performance MXene-based perovskite photocatalysts, utilizing abundant and sustainable materials for environmental remediation.
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Targeted drug delivery to tumor cells may be possible using nanoparticles containing human therapeutic drugs. The present study was carried out to develop cisplatin (CP) and 5-fluorouracil (FA) encapsulated chitosan nanoparticles (CSNPs), crosslinked with sodium tripolyphosphate (TPP) by an ionic gelation method and in vitro release, promoting antibacterial and anticancer activities. The prepared CSNPs, before and after CP and FA encapsulation, have been studied using various characterization techniques such as FTIR, XRD, SEM, and TEM-SAED patterning. The composites were well-dispersed, with an average particle size diameter of about 395.3 ± 14.3 nm, 126.7 ± 2.6 nm, and 82.5 ± 2.3 nm, respectively. In vitro release studies indicated a controlled and sustained release of CP and FA from the CSNPs, with the release amounts of 72.9 ± 3.6% and 94.8 ± 2.9%. The antimicrobial activity of the CSNPs-FA (91.37 ± 4.37% and 89.28 ± 3.19%) showed a significantly better effect against E. coli and S. aureus than that shown by the CSNPs-CP (63.41 ± 3.84% and 57.62 ± 4.28%). The HCT-116 cell lines were selected for in vitro cell cytotoxicity and live/dead assay to evaluate the preliminary anticancer efficacy of the CSNPs-CP and CSNPs-FA towards successfully inhibiting the growth of cancer cells.
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Herein, a simple hydrothermal synthesis is used to prepare multiple heteroatom-doped photoluminescent carbon dots (CDs) from thiourea (N and S source) and boric acid (B source) as precursors. The optical and physicochemical properties of the as-synthesized NSB-CDs were studied using UV-Vis, photoluminescence, TEM, FT-IR, XRD, Raman, and XPS analyses. The NSB-CDs exhibited excellent stability, high photostability, pH, and ionic strength tolerance; they retained their excellent stability independent of excitation. The NSB-CDs featured small sizes of approximately 3.2 ± 0.4 nm (range: 2.0-5.0 nm) as evidenced using TEM measurements. The NSB-CDs were used as a photoluminescent sensing platform to detect Fe3+ as well as cysteine (Cys) molecules. The competitive binding of Cys to Fe3+ resulted in NSB-CDs that retained their photoluminescence. For the rapid identification and quantification of Fe3+ and Cys, NSB-CDs were developed as a "switch-on" dual-function sensing platform. The linear detection range of Fe3+ was 0-20 µM (limit of detection [LOD]: 54.4 nM) and that of Cys was 0-50 µM (LOD: 4.9 nM). We also introduced a smartphone RGB analysis method for detecting low-concentration solutions based on digital images. The NSB-CDs showed no toxicity at 100 µg/mL. Photoluminescent probes for multicolor live-cell imaging can be used with NSB-CDs at this concentration, suggesting that NSB-CDs may be promising photoluminescent probes.
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Cisteína , Pontos Quânticos , Cisteína/análise , Boro/química , Carbono/química , Nitrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Pontos Quânticos/química , Enxofre/química , Corantes Fluorescentes/químicaRESUMO
In this study, we report the synthesis of photoluminescent (PL) nitrogen (N) and sulfur (S) co-doped carbon dots (NS-CDs) from nitazoxanide and 3-mercaptopropionic acid as a precursors via a one-pot hydrothermal methods. N and S co-doped materials allows more active sites in the CDs surface resulting in an enhancement of their PL properties. NS-CDs show bright blue PL, excellent optical properties, good water solubility, and a high quantum yield (QY) of 32.1%. The as-prepared NS-CDs were confirmed by UV-Visible, photoluminescence, FTIR, XRD and TEM analysis. An optimized excitation at 345 nm, the NS-CDs exhibited strong PL emission at 423 nm with an average size of 3.53 ± 0.25 nm. Under optimized conditions, the NS-CDs PL probe shows high selectivity with Ag+/Hg2+ ions detected, while other cations no significant changes the PL signal. The PL intensity of NS-CDs linearly quenching and enhancement with Ag+ and Hg2+ ions from 0 to 50 × 10-6 M, with the detection limit of 2.15 × 10-6 M and 6.77 × 10-7 M (S/N = 3). More interestingly, as-synthesized NS-CDs shows a strong binding to Ag+/Hg2+ ions with the PL quenching and enhancement to precise and quantitative detection of Ag+/Hg2+ ions in living cells. The proposed system was effectively utilized for the sensing of Ag+/Hg2+ ions in real samples resulting in high sensitivity and good recoveries (98.4-109.7%).
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Mercúrio , Pontos Quânticos , Carbono/química , Nitrogênio , Pontos Quânticos/química , Enxofre/química , Íons , Mercúrio/análise , ÁguaRESUMO
Tenofovir (TFR) is an antiviral drug commonly used to fight against viral diseases infection due to its good potency and high genetic barrier to drug resistance. In physiological conditions, TFR is less water soluble, more unstable, and less permeable, limiting its effective therapeutic applications. In addition to their use in treating the Coronavirus disease 2019 (COVID-19), cyclodextrins (CDs) are also being used as a molecule to develop therapies for other diseases due to its enhance solubility and stability. This study is designed to synthesize and characterization of ß-CD:TFR inclusion complex and its interaction against SARS-CoV-2 (MPro) protein (PDB ID;7cam). Several techniques were used to characterize the prepared ß-CD:TFR inclusion complex, including UV-Visible, FT-IR, XRD, SEM, TGA, and DSC, which provided appropriate evidence to confirm the formation. A 1:1 stoichiometry was determined for ß-CD:TFR inclusion complex in aqueous medium from UV-Visible absorption spectra by using the Benesi-Hildebrand method. Phase solubility studies proposed that ß-CD enhanced the excellent solubility of TFR and the stability constant was obtained at 863 ± 32 M-1. Moreover, the molecular docking confirmed the experimental results demonstrated the most desirable mode of TFR encapsulated into the ß-CD nanocavity via hydrophobic interactions and possible hydrogen bonds. Moreover, TFR was validated in the ß-CD:TFR inclusion complex as potential inhibitors against SARS-CoV-2 main protease (Mpro) receptors by using in silico methods. The enhanced solubility, stability, and antiviral activity against SARS-CoV-2 (MPro) suggest that ß-CD:TFR inclusion complexes can be further used as feasible water-insoluble antiviral drug carriers in viral disease infection.
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Heteroatom-doped photoluminescent (PL) carbon dots (CDs) have recently gained attention as optical sensors due to their excellent tunable properties. In this work, we propose a one-pot hydrothermal synthesis of PL nitrogen (N), sulfur (S), and phosphorus (P) co-doped carbon dots (NSP-CDs) using glutathione and phosphoric acid (H3PO4) as precursors. The synthesized NSP-CDs were characterized using different spectroscopic and microscopic techniques, including ultraviolet-visible (UV-Vis) spectroscopy, fluorescence spectroscopy, Fourier-transform infrared (FTIR), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) analysis. The NSP-CDs exhibited excellent PL properties with green emission at 492 nm upon excitation at 417 nm, a high quantum yield of 26.7%, and dependent emission behavior. The as-prepared NSP-CDs were spherical with a well-monodispersed average particle size of 5.2 nm. Moreover, NSP-CDs demonstrate high PL stability toward a wider pH, high salt ionic strength, and various solvents. Furthermore, the NSP-CDs showed a three-state "off-on-off" PL response upon the sequential addition of Al3+ and Fe3+ ions, with a low limit of detection (LOD) of 10.8 nM for Al3+ and 50.7 nM for Fe3+. The NSP-CD sensor can construct an INHIBIT logic gate with Al3+ and Fe3+ ions as the chemical inputs and emissions as the output mode. Owing to an excellent tunable PL property and biocompatibility, the NSP-CDs were applied for sensing Al3+ and Fe3+ ions as well as live cell imaging. Furthermore, NSP-CDs were designed as PL sensors for detecting Al3+ and Fe3+ ions in real water show their potential application.
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Carbono , Pontos Quânticos , Carbono/química , Nitrogênio/química , Pontos Quânticos/química , Enxofre/química , Íons/químicaRESUMO
Hydrogel nanocomposites are attracting increasing attention in field of biology owing to their unique properties. The present work focuses on the fabrication and characterization of novel hydrogel nanocomposite systems in which silver nanoparticles (AgNPs) are embedded in a carrageenan (κ-CGN)-sodium alginate (SA) hydrogel. The performance of the prepared κ-CGN-SA hydrogel and κ-CGN-SA/AgNPs hydrogel nanocomposite was determined by UV-visible spectroscopy, FTIR, XRD, SEM, EDX spectrum, EDX mapping, and TEM analysis. Surface plasmon resonance at 428 nm confirmed the presence of AgNPs in the κ-CGN-SA hydrogel. The results indicate that AgNPs with an average diameter of 30 nm were uniformly dispersed in the κ-CGN-SA hydrogel matrix. The amount of Ag+ ion release kinetic from the κ-CGN-SA hydrogel matrix is very low, showing that AgNPs were well trapped within the κ-CGN-SA/AgNPs hydrogel nanocomposite. The high antibacterial activity of the κ-CGN-SA/AgNPs hydrogel nanocomposite was found to be 89.6 ± 1.4% and 91.4 ± 2.3% against the gram-positive S. aureus and the gram-negative E. coli, respectively. Moreover, the κ-CGN-SA/AgNPs hydrogel nanocomposite showed good biocompatibility by the MTT test. The novel κ-CGN-SA/AgNPs hydrogel nanocomposite low cytotoxicity and antibacterial efficacy is proposed as a potential candidate for biomedical applications.
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Nanopartículas Metálicas , Nanocompostos , Nanogéis , Carragenina/química , Nanopartículas Metálicas/química , Escherichia coli , Alginatos/química , Prata/química , Staphylococcus aureus , Antibacterianos/química , Hidrogéis/química , Nanocompostos/químicaRESUMO
Nitazoxanide (NTZ), a promising antiviral agent, is currently being tested in clinical trials as a potential treatment for novel coronavirus disease 2019 (COVID -19). This paper describes a one-pot hydrothermal synthesis to prepare molybdenum (Mo)-doped manganese tungstate nanocubes (Mo-MnWO4 NCs) for the electrochemical sensing of NTZ. The as-prepared Mo-MnWO4 NCs were characterized using various techniques such as XRD, Raman, FE-SEM, FE-TEM, and XPS to confirm the crystal structure, morphology, and elemental composition. The obtained results demonstrate that Mo doping on MnWO4 generates many vacancy sites, exhibiting remarkable electrochemical activity. The kinetic parameters of the electrode modified with Mo-MnWO4 NCs were calculated to be (Ks) 1.1 × 10-2 cm2 s-1 and (α) 0.97, respectively. Moreover, a novel electrochemical sensor using Mo-MnWO4 NCs was fabricated to detect NTZ, which is used as a primary antibiotic to control COVID-19. Under optimal conditions, the electrochemical reduction of NTZ was determined with a low detection limit of 3.7 nM for a linear range of 0.014-170.2 µM with a high sensitivity of 0.78 µA µM-1 cm-2 and negligible interference with other nitro group-containing drugs, cations, and anions. The electrochemical sensor was successfully used to detect NTZ in the blood serum and urine samples and achieved high recoveries in the range of 94-99.2% and 95.3-99.6%, respectively. This work opens a way to develop high-performance sensing materials by exploring the introduction of defect engineering on metal tungstates to detect drug molecules for practical applications.
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In this study, we report the synthesis of platinum nanoparticles (Cs-PtNPs) using an aqueous extract of Caulerpa sertularioides as a reducing agent. Cs-PtNPs were characterized by UV-Vis spectroscopy, fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDAX), high-resolution transmission electron microscopy (HR-TEM) and dynamic light scattering (DLS) analysis. Cs-PtNPs are spherical with a particle size of 6-22 nm. Cs-PtNPs have been shown to have highly effective antioxidant activities with 74% for DPPH, 63% for reducing power, and 59% for total antioxidant at 1 mg/ml, and results were compared with standard L-ascorbic acid. Furthermore, the Cs-PtNPs demonstrated excellent antibacterial activity against the Gram-negative bacteria, Vibrio parahaemolyticus with the highest zone of inhibition (18 mm) at 50 µg/ml. Moreover, Artemia nauplii showed less toxicity when treated with Cs-PtNPs at 150 µg/ml, indicating that the Cs-PtNPs are less toxic and environment friendly.
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Caulerpa , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Antioxidantes/farmacologia , Antioxidantes/química , Platina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/química , Difração de Raios X , Extratos Vegetais/química , Testes de Sensibilidade MicrobianaRESUMO
During the current outbreak of the novel coronavirus disease 2019 (COVID-19), researchers have examined several antiviral drugs with the potential to inhibit the proliferation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The antiviral drug acyclovir (AVR), which is used to treat COVID-19, in complex with methyl-ß-cyclodextrin (Mß-CD) was examined in the solution and solid phases. UV-visible and fluorescence spectroscopic analyses confirmed that the guest (AVR) was included inside the host (Mß-CD) cavity. A solid inclusion complex of AVR was prepared by co-precipitation, physical mixing, kneading, and bath sonication methods at a 1:1 ratio of Mß-CD:AVR. The prepared Mß-CD:AVR inclusion complex was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) analysis. Phase solubility studies indicated the Mß-CD:AVR inclusion complex exhibited a higher stability constant and linear enhancement in AVR solubility with increasing Mß-CD concentrations. In silico analysis of the Mß-CD/AVR inclusion complex confirmed that AVR drugs show potential as inhibitors of SARS-CoV-2 3C-like protease (3CLpro) receptors. Results obtained using the PatchDock and FireDock servers indicated that the most favorable docking ligand was Mß-CD:AVR, which interacted with SARS-CoV-2 (3CLPro) protease inhibitors with high geometric shape complementarity scores (2522 and 5872) and atomic contact energy (-313.77 and -214.70 kcal mol-1). Our results suggest that the Mß-CD/AVR inclusion complex inhibits the main protease of SARS-CoV-2, although further wet-lab experiments are needed to verify these findings.
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A potentially active water-soluble anti-viral with lesser toxic material from the Oseltamivir (OTV) has been produced by the sonication method. The formed material has been further characterized by UV-visible, FT-IR, powder XRD, SEM, TGA/DTA, ROESY, XPS, AFM and etc., The results of DFT calculation have proven that inclusion complexes (ICs) are theoretically and energetically more advantageous models and structures have also been proposed based on the results. Analysis of drug release has been carried out at three pH levels, and it is revealed the analysis is most helpful at acidic pH levels for the ICs with S-CD over H-CD. Over OTV without CDs, OTV:S-CD-ICs exhibited a very less cytotoxic ability on cancer cell lines than ICs with M-CD. ICs enhanced the coronavirus inactivation nature of OTV. This study provides for the first time a full characterization of ICs of OTV with CDs and highlights the impact of complexation on pharmacological activity.
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Coronavirus , Ciclodextrinas , beta-Ciclodextrinas , Ciclodextrinas/química , Oseltamivir/farmacologia , Pós , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos , Água/química , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologiaRESUMO
A catalyst-free microwave-assisted annulation protocol for the preparation of biologically interesting pyrido-fused quinazolinones and pyrido[1,2-a]benzimidazoles is developed. This reaction involves the [3 + 3] annulation of various quinazolinones or benzimidazoles with 3-formylchromones to yield functionalized 11H-pyrido[2,1-b]quinazolin-11-one and pyrido[1,2-a] benzimidazole derivatives. This approach is successfully extended to the construction of various pyrazolo[4,3-d]pyrido[1,2-a]pyrimidin-10(1H)-ones. The present approach is complementary to the existing synthetic methodologies and offers a rapid and facile approach with a broad substrate scope, good yields, catalyst-free conditions, and a high functional group tolerance. The optimal synthesized compound is also employed as an "on-off" photoluminescent probe for the selective detection of Fe3+ and Ag+ metal ions.
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Benzimidazóis , Micro-Ondas , Benzimidazóis/química , Catálise , QuinazolinonasRESUMO
Herein, we have successfully synthesized a novel nCS-PDMA/AuNPs nanocomposite based on nano-chitosan containing poly(2,5-dimethoxyaniline) capped gold nanoparticle in situ synthesis is reported. The AuNPs were synthesized using the green method without using any harmful chemicals, reducing and stabilizing agents to generate AuNPs, is not needed because these roles are played by nCS. The synthesized nCS-PDMA/AuNPs nanocomposite were characterized by UV-Vis, FT-IR, XRD, SEM, and TEM analysis. The polydispersed nCS-PDMA/AuNPs nanocomposite was observed approximately 25 nm. Furthermore, nCS-PDMA/AuNPs nanocomposite was showed significant antibacterial activity against S. aureus and E. coli. The nCS-PDMA/AuNPs nanocomposite showed strong antioxidant activity by inhibiting the DPPH radicals. In addition, the cytotoxicity of nCS-PDMA/AuNPs nanocomposite was tested in HeLa cells and found to be high toxicity than nCS-PDMA. This work suggests that green synthesized nCS-PDMA/AuNPs nanocomposite may be utilized as an effective antibacterial, antioxidant, and anticancer activity.[Figure: see text]Research highlightsnCS-PDMA capped gold nanoparticles (nCS-PDMA/AuNPs) were prepared.Physical characterization of nCS-PDMA/AuNPs by UV-vis, FTIR, XRD, SEM, and TEM.nCS-PDMA/AuNPs displayed promising inhibitory activity against both bacteria.nCS-PDMA/AuNPs showed significant DPPH radical scavenging activities.nCS-PDMA/AuNPs showed an excellent anticancer activity against HeLa cells.
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Quitosana , Nanopartículas Metálicas , Nanocompostos , Compostos de Anilina , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Quitosana/química , Escherichia coli , Ouro/química , Células HeLa , Humanos , Nanopartículas Metálicas/química , Nanocompostos/química , Polímeros , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureusRESUMO
An effective method for reducing silver ions using gelatin (Gel) and 2-hydroxypropyl-ß-cyclodextrin (HPCD) hydrogels, which stabilize silver at various concentrations is described. The formation of AgNPs in solution, as well as Gel-HPCD nanogels, is confirmed by the surface plasmon resonance (SPR) band at 420-440 nm in the UV-Vis spectrum. The resulting Gel-HPCD and Gel-HPCD/AgNPs composites are characterized using various techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), and thermogravimetric analysis (TGA). SEM images showed that the porous structure and the AgNPs are homogeneously dispersed throughout the Gel-HPCD/AgNP composites network. The AgNPs in the Gel-HPCD/AgNPs composite is crystalline, with spherical particles having an average size of 7.0 ± 2.5 nm, as determined by TEM. The Gel-HPCD/AgNPs composites are strongly effective against both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. The assembled antibacterial Gel-HPCD/AgNPs composites are also assessed for their cytotoxic and anticancer activities using HCT-116 cancer cells. The results suggest that Gel-HPCD/AgNPs composites could be used as effective therapeutics in the future in tissue engineering applications, as their bactericidal properties and low toxicity make them ideal for clinical use.