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1.
ACS Omega ; 9(13): 15239-15250, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38585078

ABSTRACT

A novel integrated electrochemical oxidation (EO) and bacterial degradation (BD) technique was employed for the remediation of the chloropyridinyl and chlorothiazolyl classes of neonicotinoid (NEO) insecticides in the environment. Imidacloprid (IM), clothianidin (CL), acetamiprid (AC), and thiamethoxam (TH) were chosen as the target NEOs. Pseudomonas oleovorans SA2, identified through 16S rRNA gene analysis, exhibited the potential for BD. In EO, for the selected NEOs, the total percentage of chemical oxygen demand (COD) was noted in a range of 58-69%, respectively. Subsequently, in the biodegradation of EO-treated NEOs (BEO) phase, a higher percentage (80%) of total organic carbon removal was achieved. The optimum concentration of NEOs was found to be 200 ppm (62%) for EO, while for BEO, the COD efficiency was increased up to 79%. Fourier-transform infrared spectroscopy confirms that the heterocyclic group and aromatic ring were degraded in the EO and further utilized by SA2. Gas chromatography-mass spectroscopy indicated up to 96% degradation of IM and other NEOs in BD (BEO) compared to that of EO (73%). New intermediate molecules such as silanediamine, 1,1-dimethyl-n,n'-diphenyl produced during the EO process served as carbon sources for bacterial growth and further mineralized. As a result, BEO enhanced the removal of NEOs with a higher efficiency of COD and a lower consumption of energy. The removal efficiency of the NEOs by the integrated approach was achieved in the order of AC > CL > IM > TH. This synergistic EO and BD approach holds promise for the efficient detoxification of NEOs from polluted environments.

2.
Front Microbiol ; 15: 1297721, 2024.
Article in English | MEDLINE | ID: mdl-38544856

ABSTRACT

Background: Cooling towers are specialized heat exchanger devices in which air and water interact closely to cool the water's temperature. However, the cooling water contains organic nutrients that can cause microbial corrosion (MC) on the metal surfaces of the tower. This research explores the combined wastewater treatment approach using electrochemical-oxidation (EO), photo-oxidation (PO), and photoelectrochemical oxidation (PEO) to contain pollutants and prevent MC. Methods: The study employed electro-oxidation, a process involving direct current (DC) power supply, to degrade wastewater. MC studies were conducted using weight loss assessments, scanning electron microscopy (SEM), and x-ray diffraction (XRD). Results: After wastewater is subjected to electro-oxidation for 4 h, a notable decrease in pollutants was observed, with degradation efficiencies of 71, 75, and 96%, respectively. In the wastewater treated by PEO, microbial growth is restricted as the chemical oxygen demand decreases. Discussion: A metagenomics study revealed that bacteria present in the cooling tower water consists of 12% of Nitrospira genus and 22% of Fusobacterium genus. Conclusively, PEO serves as an effective method for treating wastewater, inhibiting microbial growth, degrading pollutants, and protecting metal from biocorrosion.

3.
Environ Geochem Health ; 46(3): 81, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38367190

ABSTRACT

This study presents an environmentally sustainable method for minimizing sludge production in the textile effluent sector through the combined application of electrokinetic (EK) and electrooxidation (EO) processes. AAS and XRF analyses reveal that utilizing acidic electrolytes in the EK method successfully eliminates heavy metals (Cu, Mn, Zn, and Cr) from sludge, demonstrating superior efficiency compared to alkaline conditions. In addition, the total removal efficiency of COD contents was calculated following the order of EK-3 (60%), EK-1 (51%) and EK-2 (34%). Notably, EK-3, leveraging pH gradient fluctuations induced by anolyte in the catholyte reservoir, outperforms other EK systems in removing COD from sludge. The EK process is complemented by the EO process, leading to further degradation of dye and other organic components through the electrochemical generation of hypochlorite (940 ppm). At an alkaline pH of 10.0, the color and COD removal were effectively achieved at 98 and 70% in EO treatment, compared to other mediums. In addition, GC-MS identified N-derivative residues at the end of the EO. This study demonstrates an integrated approach that effectively eliminates heavy metals and COD from textile sludge, combining EK with EO techniques.


Subject(s)
Metals, Heavy , Sewage , Sewage/chemistry , Metals, Heavy/analysis , Textiles
4.
Environ Res ; 242: 117753, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38008204

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are potentially hazardous compounds that could cause a severe impact on many ecosystems. They are very challenging to remove using conventional methods due to their hydrophobic nature. However, this issue can be resolved by utilizing surface-active molecules to increase their bioavailability. In this study, pyrene was chosen as the PAH compound to explore its degradability by the effect of individual bacterial strains (Pseudomonas stutzeri NA3 and Acinetobacter baumannii MN3) and mixed consortia (MC) along with natural surfactant derived from Sapindus mukorossi and iron oxide nanoparticles (NPs). Additionally, fatty acids esters, dipeptides, and sugar derivative groups were identified as potent bioactive components of natural surfactants. Various techniques, such as XRD, VSM, TEM, and FE-SEM with EDX, were utilized to characterize the pristine and Fenton-treated iron oxide NPs. The analytical results confirmed that the Fe3O4 crystal phase and spherical-shaped NPs exhibited excellent magnetic properties. The impact of natural surfactants and iron oxide NPs has significantly contributed to the biodegradation process, resulting in a prominent decrease in chemical oxygen demand (COD) levels. Gas chromatography-mass spectrometry (GC-MS) analysis showed that biodegradation systems produced primary hydrocarbon intermediates, which underwent oxidative degradation through Fenton treatment. Interestingly, synthesized iron oxide NPs effectively produced hydroxyl radical (•OH) during the Fenton reaction, which was confirmed by electron paramagnetic resonance (EPR) spectra, and the pristine iron oxide NPs underwent a material transformation observed. The study demonstrated an integrated approach for biodegradation and the Fenton reaction process to enhance the pyrene degradation efficiency (90%) compared to other systems. Using natural surfactants and iron oxide NPs in aquatic environments serves as a crucial platform at the interface of microorganisms and contaminated oil products. This interaction offers a promising solution for PAHs bioremediation.


Subject(s)
Ferric Compounds , Polycyclic Aromatic Hydrocarbons , Soil Pollutants , Surface-Active Agents/chemistry , Biodegradation, Environmental , Ecosystem , Soil Pollutants/analysis , Pyrenes/metabolism , Polycyclic Aromatic Hydrocarbons/metabolism , Bacteria/metabolism , Magnetic Iron Oxide Nanoparticles
5.
Environ Res ; 244: 117911, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38104919

ABSTRACT

Poly aromatic hydrocarbons (PAHs) are considered as hazardous compounds which causes serious threat to the environment dua to their more carcinogenic and mutagenic impacts. In this study, Pseudomonas aeruginosa PP4 strain and synthesized iron nanoparticles were used to evaluate the biodegradation efficiency (BE %) of residual anthracene. The BE (%) of mixed degradation system (Anthracene + PP4+ FeNPs) was obtained about 67 %. The FTIR spectra result revealed the presence of functional groups (C-H, -CH3, CC, =C-H) in the residual anthracene. The FESEM and TEM techniques were used to determine the surface analysis of the synthesized FeNPs and the average size was observed by TEM around 5-50 nm. The crystalline nature of the synthesized iron nanoparticles was confirmed by the observed different respective peaks of XRD pattern. The various functional constituents (OH, C-H, amide I, CH3) were identified in the synthesized iron nanoparticles by FTIR spectrum. In conclusion, this integrated nano-bioremediation approach could be an promising and effective way for many environmental fields like cleanup of hydrocarbon rich environment.


Subject(s)
Anthracenes , Pseudomonas aeruginosa , Anthracenes/metabolism , Iron , Biodegradation, Environmental , Magnetic Iron Oxide Nanoparticles
6.
J Pharm Sci ; 2023 Dec 24.
Article in English | MEDLINE | ID: mdl-38147911

ABSTRACT

In today's context, prolonged exposure to sunlight is widely recognized as a threat to human health, leading to a range of adverse consequences, including skin cancers, premature skin aging, and erythema. To mitigate these risks, preventive actions mainly focus on advocating the application of sunscreen lotions and minimizing direct exposure to sunlight. This research study specifically centered on ensulizole (ENS), a prominent ingredient in sunscreens. The objective was to create inclusion complexes (ICs) with Beta-cyclodextrin (B-CD) and its hydroxypropyl derivatives (H-CD). Using phase solubility measurements, we determined that both B-CD and H-CD form 1:1 stoichiometric ICs with ENS. Proton nuclear magnetic resonance spectral (1H NMR) analysis confirmed that the phenyl portion of ENS is encapsulated within the B-CD cavity. Significant changes in surface morphology were observed during the formation of these ICs compared to ENS and CDs alone. Quantum mechanical calculations were employed to further support the formation of ICs by providing energy data. Particularly, the photostability of the ENS:B-CD ICs remained intact for up to four hours of UV exposure, with no significant alterations in the structure of ENS. Furthermore, comprehensive biocompatibility assessments yielded encouraging results, suggesting the potential application of these inclusion complexes in cosmetics as a UVB sunscreen. In summary, our research underscores the successful creation of inclusion complexes characterized by enhanced photostability and safe biocompatibility.

7.
Chemosphere ; 345: 140516, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37879370

ABSTRACT

Azo dyes are the most varied class of synthetic chemicals with non-degradable characteristics. They are complex compounds made up of many different parts. It was primarily utilized for various application procedures in the dyeing industry. Therefore, it's crucial to develop an economical and environmentally friendly approach to treating azo dyes. Our present investigation is an integrated approach to the electrooxidation (EO) process of azo dyes using RuO2-IrO2-TiO2 (anode) and titanium mesh (cathode) electrodes, followed by the biodegradation process (BD) of the treated EO dyes. Chemical oxygen demand (COD) removal efficiency as follows MB (55%) ≥ MR (45%) ≥ TB (38%) ≥ CR (37%) correspondingly. The fragment generated during the degradation process which was identified with high-resolution mass spectrometry (HRMS) and its degradation mechanism pathway was proposed as demethylation reaction and N-N and C-N/C-S cleavage reaction occurs during EO. In biodegradation studies by Aeromonas hydrophila AR1, the EO treated dyes were completely mineralized aerobically which was evident by the COD removal efficiency as MB (98%) ≥ MR (92.9%) ≥ TB (88%) ≥ CR (87%) respectively. The EO process of dyes produced intermediate components with lower molecular weights, which was effectively utilized by the Aeromonas hydrophila AR1 and resulted in higher degradation efficiency 98%. We reported the significance of the enhanced approach of electrochemical oxidation with biodegradation studies in the effective removal of the pollutants in dye industrial effluent contaminated water environment.


Subject(s)
Aeromonas hydrophila , Water Pollutants, Chemical , Azo Compounds/chemistry , Oxidation-Reduction , Titanium/chemistry , Coloring Agents/chemistry , Electrodes , Water Pollutants, Chemical/analysis
8.
Chemosphere ; 344: 140340, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37778647

ABSTRACT

Biosurfactants are surface active molecules generated by various microorganisms, including bacteria, actinobacteria, algae, and fungi. In this study, bacterial strains are isolated from soil contaminated with used motor oil and examined for potential biosurfactant production. A minimum salt medium (MSM), with crude oil as the only carbon source, is used to isolate potential biosurfactant-producing bacterial strains. About 23 strains are isolated, and all are subjected to the primary screening methods for biosurfactant production. Based on the emulsification index, oil displacement, and drop collapse screening methods, two isolates with potential biosurfactant-producing ability are selected for further studies. The synthesis of biosurfactants, crude oil and anthracene biodegradation is carried out with strains DTS1 and DTS2. Both strains show significant outcomes in crude oil degradation. In addition, both strains can utilize anthracene as the sole carbon source. During the degradation course, changes in the growth conditions are continuously monitored by measuring turbidity and pH. In this degradation study, the biosurfactant production aptitude of the isolated strains plays an essential role in increasing the bioavailability of hydrophobic hydrocarbons. These strains are identified down to the molecular level by employing 16S rRNA gene sequencing, and the acquired sequences are submitted to get the accession numbers. These prospective strains can be utilized to remediate hydrocarbon-contaminated environments.


Subject(s)
Bacillus , Petroleum , Bacillus/metabolism , Petroleum/analysis , RNA, Ribosomal, 16S/genetics , Prospective Studies , Surface-Active Agents/chemistry , Bacteria/metabolism , Hydrocarbons/metabolism , Biodegradation, Environmental , Anthracenes/metabolism , Carbon/metabolism
9.
Micromachines (Basel) ; 14(7)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37512663

ABSTRACT

Quercetin (QRC), a flavonoid found in foods and plants such as red wine, onions, green tea, apples, and berries, possesses remarkable anti-inflammatory and antioxidant properties. These properties make it effective in combating cancer cells, reducing inflammation, protecting against heart disease, and regulating blood sugar levels. To enhance the potential of inclusion complexes (ICs) containing ß-cyclodextrin (ß-CD) in cancer therapy, they were transformed into nano-inclusion complexes (NICs). In this research, NICs were synthesized using ethanol as a reducing agent in the nanoprecipitation process. By employing FT-IR analysis, it was observed that hydrogen bonds were formed between QRC and ß-CD. Moreover, the IC molecules formed NICs through the aggregation facilitated by intermolecular hydrogen bonds. Proton NMR results further confirmed the occurrence of proton shielding and deshielding subsequent to the formation of NICs. The introduction of ß-CDs led to the development of a distinctive feather-like structure within the NICs. The particle sizes were consistently measured around 200 nm, and both SAED and XRD patterns indicated the absence of crystalline NICs, providing supporting evidence. Through cytotoxicity and fluorescence-assisted cell-sorting analysis, the synthesized NICs showed no significant damage in the cell line of MCF-7. In comparison to QRC alone, the presence of high concentrations of NICs exhibited a lesser degree of toxicity in normal human lung fibroblast MRC-5 cells. Moreover, the individual and combined administration of both low and high concentrations of NICs effectively suppressed the growth of cancer cells (MDA-MB-231). The solubility improvement resulting from the formation of QRC-NICs with ß-CD enhanced the percentage of cell survival for MCF-7 cell types.

10.
Biomolecules ; 13(7)2023 07 20.
Article in English | MEDLINE | ID: mdl-37509190

ABSTRACT

Recently, researchers have employed metal-organic frameworks (MOFs) for loading pharmaceutically important substances. MOFs are a novel class of porous class of materials formed by the self-assembly of organic ligands and metal ions, creating a network structure. The current investigation effectively achieves the loading of adenosine (ADN) into a metal-organic framework based on cyclodextrin (CD) using a solvent diffusion method. The composite material, referred to as ADN:ß-CD-K MOFs, is created by loading ADN into beta-cyclodextrin (ß-CD) with the addition of K+ salts. This study delves into the detailed examination of the interaction between ADN and ß-CD in the form of MOFs. The focus is primarily on investigating the hydrogen bonding interaction and energy parameters through the aid of semi-empirical quantum mechanical computations. The analysis of peaks that are associated with the ADN-loaded ICs (inclusion complexes) within the MOFs indicates that ADN becomes incorporated into a partially amorphous state. Observations from SEM images reveal well-defined crystalline structures within the MOFs. Interestingly, when ADN is absent from the MOFs, smaller and irregularly shaped crystals are formed. This could potentially be attributed to the MOF manufacturing process. Furthermore, this study explores the additional cross-linking of ß-CD with K through the coupling of -OH on the ß-CD-K MOFs. The findings corroborate the results obtained from FT-IR analysis, suggesting that ß-CD plays a crucial role as a seed in the creation of ß-CD-K MOFs. Furthermore, the cytotoxicity of the MOFs is assessed in vitro using MDA-MB-231 cells (human breast cancer cells).


Subject(s)
Cyclodextrins , Metal-Organic Frameworks , Neoplasms , beta-Cyclodextrins , gamma-Cyclodextrins , Humans , Metal-Organic Frameworks/chemistry , Spectroscopy, Fourier Transform Infrared , Cyclodextrins/chemistry , beta-Cyclodextrins/chemistry , Neoplasms/drug therapy
11.
Molecules ; 28(9)2023 Apr 23.
Article in English | MEDLINE | ID: mdl-37175077

ABSTRACT

The loading of drugs or medicinally active compounds has recently been performed using metal-organic frameworks (MOFs), which are thought to be a new type of porous material in which organic ligands and metal ions can self-assemble to form a network structure. The quercetin (QRC) loading and biofilm application on a cyclodextrin-based metal-organic framework via a solvent diffusion approach is successfully accomplished in the current study. The antibacterial plant flavonoid QRC is loaded onto ß-CD-K MOFs to create the composite containing inclusion complexes (ICs) and denoted as QRC:ß-CD-K MOFs. The shifting in the chemical shift values of QRC in the MOFs may be the reason for the interaction of QRC with the ß-CD-K MOFs. The binding energies and relative contents of MOFs are considerably changed after the formation of QRC:ß-CD-K MOFs, suggesting that the interactions took place during the loading of QRC. Confocal laser scanning microscopy (CLSM) showed a reduction in the formation of biofilm. The results of the cell aggregation and hyphal growth are consistent with the antibiofilm activity that is found in the treatment group. Therefore, QRC:ß-CD-K MOFs had no effect on the growth of planktonic cells while inhibiting the development of hyphae and biofilm in C. albicans DAY185. This study creates new opportunities for supramolecular ß-CD-based MOF development for use in biological research and pharmaceutical production.


Subject(s)
Metal-Organic Frameworks , beta-Cyclodextrins , Metal-Organic Frameworks/pharmacology , Metal-Organic Frameworks/chemistry , Antifungal Agents/pharmacology , Quercetin/pharmacology , beta-Cyclodextrins/pharmacology , Biofilms
12.
J Biomater Sci Polym Ed ; 34(14): 1911-1927, 2023 10.
Article in English | MEDLINE | ID: mdl-37042185

ABSTRACT

In the past 15 years or more, interest in polymer-mediated nanofibers (NFs), a significant class of nanomaterials, has grown. Although fibers with a diameter of less than 1 mm are frequently commonly referred to as NFs, and are typically defined as having a diameter of less than several hundreds of nanometers. Due to the increased antibiotic resistance of many diseases nowadays, NFs with antibacterial activity are quite important. A flexible technique for creating NFs with the desired characteristics is called electrospinning. This research article describes how to make electrospun NFs of tannic acid (TA) with polyvinylidene fluoride (PVDF) as the template. As a result, the absorbance of the obtained NFs has been raised without forming any additional peaks in the spectral ranges. The obtained NF has a gradual increase in intensity, and the FT-IR data show that the TA is present in the NFs. FE-SEM images show that the NFs are discovered to be completely bead-free. Since TA reduced the viscosity of the spinning solution while marginally increasing solution conductivity, PVDF NFs have a greater average fiber diameter (AFD) than NFs of TA with PVDF, which is likely a result of the TA solutions in it. The findings showed that TA greatly decreased S. aureus and E. coli's ability to attach. The acquired NFs created in this work may have significant potential for reducing the pathogenicity of S. aureus and E. coli as well as their ability to build biofilms.


Subject(s)
Nanofibers , Staphylococcus aureus , Escherichia coli , Spectroscopy, Fourier Transform Infrared , Anti-Bacterial Agents/pharmacology
13.
Micromachines (Basel) ; 14(2)2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36838156

ABSTRACT

The exceptional characteristics of bio-synthesized copper oxide nanoparticles (CuO NPs), including high surface-to-volume ratio and high-profit strength, are of tremendous interest. CuO NPs have cytotoxic, catalytic, antibacterial, and antioxidant properties. Fruit peel extract has been recommended as a valuable alternative method due to the advantages of economic prospects, environment-friendliness, improved biocompatibility, and high biological activities, such as antioxidant and antimicrobial activities, as many physical and chemical methods have been applied to synthesize metal oxide NPs. In the presence of apple peel extract and microwave (MW) irradiation, CuO NPs are produced from the precursor CuCl2. 2H2O. With the help of TEM analysis, and BET surface area, the average sizes of the obtained NPs are found to be 25-40 nm. For use in antimicrobial applications, CuO NPs are appropriate. Disk diffusion tests were used to study the bactericidal impact in relation to the diameter of the inhibition zone, and an intriguing antibacterial activity was confirmed on both the Gram-positive bacterial pathogen Staphylococcus aureus and Gram-negative bacterial pathogen Escherichia coli. Moreover, CuO NPs did not have any toxic effect on seed germination. Thus, this study provides an environmentally friendly material and provides a variety of advantages for biomedical applications and environmental applications.

14.
J Pharm Biomed Anal ; 221: 115057, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36126612

ABSTRACT

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.


Subject(s)
Coronavirus , Cyclodextrins , beta-Cyclodextrins , Cyclodextrins/chemistry , Oseltamivir/pharmacology , Powders , Solubility , Spectroscopy, Fourier Transform Infrared , Sulfates , Water/chemistry , beta-Cyclodextrins/chemistry , beta-Cyclodextrins/pharmacology
15.
J Biomater Sci Polym Ed ; 33(10): 1256-1268, 2022 07.
Article in English | MEDLINE | ID: mdl-35263238

ABSTRACT

With the thought and strong hope of uniqueness and challenging characteristic highlights and importance of nanofibrous mats (NFMs) along with cyclodextrins (CDs) that having a significant opportunity, chances and handling a vital role in hostile to bacterial activities. For the most part, CDs are utilized to upgrade the antibacterial activity through the improvement of solubility, stability, and etc., to any molecule which can bring inside the CDs cavity via the formation of inclusion complexes. Polymer-mediated electrospun nanofibrous mats (PAN NFMs) are utilized as a nanocarrier for antibacterial activity in this article, utilizing nortriptyline (NP) as a reference molecule. As a result, NP forms an inclusion complex with ß-Cyclodextrin (ß-CD). As a result, the PAN NFMs are able to absorb it, thereby consolidating the complex NP on the nanofibrous surface. Additionally, the soaking of PAN NFMs in NP solution without ß-CD was performed for comparison. To characterize the nanofibrous mats of NP/PAN and NP:ß-CD-ICs/PAN NFMs, UV absorption, FTIR, Raman, XRD, and SEM techniques were used. The antibacterial activity of NP and NP:ß-CD-ICs have been tried against positive control antibiotics by the disc diffusion method. Thus, the action has been improved for NP:ß-CD-ICs/PAN NFMs over NP/PAN NFMs because of the solubility upgraded for the NP by the complexation of ß-CD.


Subject(s)
Cyclodextrins , Nanofibers , beta-Cyclodextrins , Anti-Bacterial Agents/pharmacology , Nortriptyline/pharmacology , Polymers , Solubility
16.
Materials (Basel) ; 16(1)2022 Dec 26.
Article in English | MEDLINE | ID: mdl-36614555

ABSTRACT

The unique semiconductor and optical properties of copper oxides have attracted researchers for decades. However, using fruit waste materials such as peels to synthesize the nanoparticles of copper oxide (CuO NPs) has been rarely described in literature reviews. The main purpose of this part of the research was to report on the CuO NPs with the help of apple peel extract under microwave irradiation. Metal salts and extracts were irradiated at 540 W for 5 min in a microwave in a 1:2 ratio. The crystallinity of the NPs was confirmed by the XRD patterns and the crystallite size of the NPs was found to be 41.6 nm. Elemental mapping of NPs showed homogeneous distributions of Cu and O. The NPs were found to contain Cu and O by EDX and XPS analysis. In a test involving two human pathogenic microbes, NPs showed antibacterial activity and the results revealed that the zone of inhibition grew significantly with respect to the concentration of CuO NPs. In a biofilm, more specifically, NPs at 25.0 µg/mL reduced mean thickness and biomass values of S. aureus and E. coli biofilms by >85.0 and 65.0%, respectively, with respect to untreated controls. In addition, environmentally benign materials offer a number of benefits for pharmaceuticals and other biomedical applications as they are eco-friendly and compatible.

17.
J Fluoresc ; 27(2): 689-699, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27957712

ABSTRACT

The formation of stable inclusion complexes between neutral and monocationic species of 2-aminobenzothiazole (2ABT) with ß-CDx is observed with significant enhancement in absorbance and fluorescence intensity. The stoichiometry of the 2ABT and 2ABTH⊕ with ß-CDx is found to be 1:1 at pH 6.8 and 1.1. Their binding constant values for neutral and monocationic species are found to be 1239.3 and 1259.2 M-1, respectively. Lifetime analysis, FT-IR spectral and SEM image analysis strongly supports the formation of the inclusion complex between 2ABT and ß-CDx. Photoprototropic study shows that there is no remarkable difference in the pK a and pK a* in aqueous and ß-CDx media, which is rules out the formation of the inclusion complex with -NH2 group of 2ABT inside the cavity of ß-CDx i.e., the -NH2 group of 2ABT is in aqueous environment. Based on stoichiometry, binding constant and acidity constant values, the structure of the 1:1 complex is proposed.

18.
Article in English | MEDLINE | ID: mdl-25829161

ABSTRACT

Inosine is a nucleoside that is formed when hypoxanthine is attached to a ribose ring (also known as a ribofuranose) via a ß-N9-glycosidic bond. Inosine is commonly found in tRNAs. Inosine (INS) has been used widely as an antiviral drug. The inclusion complex of INS with ß-CDx in solution phase is studied by ground and excited state with UV-visible and fluorescence spectroscopy, respectively. A binding constant and stoichiometric ratio between INS and ß-CDx are calculated by BH equation. The lifetime and relative amplitude of INS is increases with increasing the concentrations of ß-CDx, confirms the formation of inclusion complex in liquid state. The solid complexes are prepared by kneading method (KM) and co-precipitation method (CP). The solid complex is characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and differential scanning colorimetry (DSC). CP method gives the solid product with good yield than that of physical mixture and KM method. The structure of complex is proposed based on the study of Patch - Dock server.


Subject(s)
Antiviral Agents/administration & dosage , Inosine/administration & dosage , beta-Cyclodextrins/chemistry , Antiviral Agents/chemistry , Calorimetry, Differential Scanning , Inosine/chemistry , Microscopy, Electron, Scanning , Molecular Docking Simulation , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
19.
Article in English | MEDLINE | ID: mdl-21900038

ABSTRACT

Spectral characteristics of diphenylamine (DPA) have been investigated in ß-cyclodextrin (ß-CDx) solution. The formation of the complex was revealed by UV, steady state and time-resolved fluorescence spectroscopy. The stoichiometry of DPA:ß-CDx complex, determined using Benesi-Hildebrand equation and Job's continuous variation method is 1:1. The binding constants calculated from various methods are reported. This inclusion complex formation from DPA and ß-CDx was also confirmed by the FT-IR spectral study and SEM image analysis of solid complex prepared by co-precipitation method.


Subject(s)
Diphenylamine/chemistry , beta-Cyclodextrins/chemistry , Spectrometry, Fluorescence , Spectroscopy, Fourier Transform Infrared
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 77(2): 473-7, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20634124

ABSTRACT

The photophysical and photoprototropic properties of 3,3'-diaminodiphenylsulphone (3DADPS) in aqueous beta-cyclodextrin (beta-CDx) solution have been investigated using absorption and fluorescence spectral techniques. beta-CDx forms 1:1 inclusion complex with 3DADPS as revealed by steady state and time-resolved fluorescence spectroscopy. This inclusion complex formation was also confirmed by the FT-IR and SEM image analysis of solid complex prepared by co-precipitation method. The existence of twisted intramolecular charge transfer state and the unusual red shift observed during inclusion complexation were analyzed and discussed. The ground and excited state acidity constants in beta-CDx are reported. Based on the photophysical and photoprototropic characteristics of 3DADPS in beta-CDx, the structure of the 1:1 inclusion complex is proposed.


Subject(s)
Dapsone/chemistry , Fluorometry/methods , beta-Cyclodextrins/chemistry , Microscopy, Electron, Scanning , Molecular Structure , Spectrometry, Fluorescence/methods , Spectroscopy, Fourier Transform Infrared
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