Displaying publications 61 - 80 of 992 in total

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  1. Sucinda EF, Abdul Majid MS, Ridzuan MJM, Sultan MTH, Gibson AG
    Int J Biol Macromol, 2020 Jul 15;155:241-248.
    PMID: 32240733 DOI: 10.1016/j.ijbiomac.2020.03.199
    Cellulose nanowhisker (NWC) was extracted by hydrolysing Pennisetum purpureum (PP) fibres with acid and alkali. They were subjected to different periods of acid hydrolysis; 30, 45, and 60 min. NWC morphology and physicochemical properties were characterised by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), particle size analyser, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and thermogravimetric analysis. NWC3, which underwent the longest hydrolysis time, showed the smallest width and length, under TEM. All samples presented a needle-like shape under TEM and AFM; uneven lengths and irregular shapes under FESEM; and a broad range of distribution, with the particle size analyser. All samples exhibited a good crystallinity index (CrI)-72.0 to 74.6%. The highest CrI% corresponded to 60 min of acid hydrolysis. Thermogravimetric analysis showed thermal stability between 310.72 °C and 336.28 °C. Thus, cellulose nanowhisker from PP fibres, have high potential as bio-nanocomposites.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  2. Haroun M, Idris A, Omar S
    J Hazard Mater, 2009 Jun 15;165(1-3):111-9.
    PMID: 18990495 DOI: 10.1016/j.jhazmat.2008.09.092
    The major limitation of direct application of tannery sludge compost in agriculture is the total heavy metal contents and their bioavailability to the soil-plant system. This study focused on the heavy metal characterization and the influence of changing the physicochemical properties of the medium throughout the composting on the concentrations, bioavailability or chemical forms of Cr, Cu, Zn, Pb and Cd in tannery sludge. The study shows that throughout the 60 days of composting, physicochemical analysis and Fourier-transformed infrared (FTIR) spectroscopic characterization show that all parameters elaborated and reached relatively stable levels reflecting the stability and maturity of the final product, and revealed the biodegradation of components that can be easily assimilated by microorganism. The C/N ratio reaches the optimal range of stable compost; inorganic nitrogen is transformed into stable organic forms. The total concentration of Cr, Zn, Cu, Pb and Cd is very low rendering final compost acceptable for agricultural use. The germination index for both Chinese cabbage and lettuce was 97% after 60 days of composting, showing that the final compost was not phytotoxic. Furthermore, in using a sequential extraction method in sludge compost at different phases of treatment, a less than 2% of metals bound to bioavailable fractions X-(KNO(3)+H(2)O). A large proportion of the heavy metals were associated to the residual fraction (75-85%) and more resistant fractions to extraction X-NaOH, X-EDTA, X-HNO(3) (15-25%). Mobile fractions of metals are poorly predictable from the total content. Bioavailability of all fractions of elements tends to decrease.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  3. Krisnaiah, Duduku, Yan, Yan Farm, Awang Bono, Noor Maizura Ismail, Lee, Muei Chng
    MyJurnal
    Synthesis of carboxymethylcellulose (CMC) from natural cellulose is an important industrial process. The effect of process parameters on the synthesis process is important information for the efficiency improvement of production process. Most of the previous studies on the effect of process parameters
    on the synthesis of CMC are based on the One-Factor-At-Time (OFAT); therefore, in this work, the response surface methodology (RSM) was used. Here, the cellulose was converted to CMC through
    carboxymethylation process using a technique of William etherification in heterogeneous system. The process parameters studied include the solvent ratio, reaction temperature and reactant ratio (molar ratio of NaOH to SMCA). Meanwhile, the analysis and optimization of the responses of the process, degree of substitution (DS) and yield were also performed using the response surface methodology. The validity of the synthesis process was identified by the determination of CMC spectrum using the fast Fourier infrared spectrometer (FTIR). The analysis of the results shows that carboxymethylation is strongly affected by combination of process parameters studied. The results obtained also show that the optimum responses, degree of substitution (DS) is 0.87 and yield is 1.80, whereas the optimum process parameters, solvent ratio is 0.70v/v, reaction temperature at 56.03oC, and molar ratio of NaOH to SMCA at 1.00mol/mol. These findings conclude that the DS and yield of carboxymethylation of cellulose are strongly affected by the combination of the process parameters.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  4. Eff ARY, Huri HZ, Radji M, Mun'im A, Suyatna FD, Eden Y
    BMC Complement Med Ther, 2023 Feb 20;23(1):56.
    PMID: 36803524 DOI: 10.1186/s12906-023-03889-x
    BACKGROUND: Mahkota Dewa [Phaleria macrocarpa (Scheff) Boerl.] fruit in vitro and in- vivo can decrease and prevent elevation of the blood pressure, lower plasma glucose levels, possess an antioxidant effect, and recover liver and kidney damage in rats. This study aimed to determine the structure and inhibitory activity of angiotensin-converting enzyme inhibitors (ACE) from the Mahkota Dewa fruit.

    METHODS: The fruit powder was macerated using methanol and then partitioned by hexane, ethyl acetate, n-butanol, and water. The fractions were chromatographed on the column chromatography and incorporated with TLC and recrystallization to give pure compounds. The structures of isolated compounds were determined by UV-Visible, FT-IR, MS, proton (1H-NMR), carbon (13C-NMR), and 2D-NMR techniques encompassing HMQC and HMBC spectra. The compounds were evaluated for their ACE inhibitory activity, and the strongest compound was determined by the kinetics enzyme inhibition.

    RESULTS: Based on the spectral data, the isolated compounds were determined as 6,4-dihydroxy-4-methoxybenzophenone-2-O-β-D-glucopyranoside (1), 4,4'-dihydroxy-6-methoxybenzophenone-2-O-β-D-glucopyranoside (2) and mangiferin (3). IC50 values of the isolated compounds 1, 2 and 3 were 0.055, 0.07, and 0.025 mM, respectively.

    CONCLUSION: The three compounds have ACE inhibitor and mangiferin demonstrated the best ACE inhibitory activity with competitive inhibition on ACE with the type of inhibition kinetics is competitive inhibition.

    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  5. Kumar GP, Sanganal JS, Phani AR, Manohara C, Tripathi SM, Raghavendra HL, et al.
    Pharmacol Res, 2015 Oct;100:47-57.
    PMID: 26232590 DOI: 10.1016/j.phrs.2015.07.025
    6-Mercaptopurine is a cytotoxic and immunosuppressant drug. The use of this drug is limited due to its poor bioavailability and short plasma half-life. In order to nullify these drawbacks, 6-mercaptopurine-chitosan nanoparticles (6-MP-CNPs) were prepared and evaluated to study the influence of preparation conditions on the physicochemical properties by using DLS, SEM, XRD and FTIR. The in vitro drug release profile at pH 4.8 and 7.4 revealed sustained release patterns for a period of 2 days. The nanoformulations showed enhanced in vitro anti-cancer activities (MTT assay, apoptosis assay, cell cycle arrest and ROS indices) on HT-1080 and MCF-7 cells. In vivo pharmacokinetics profiles of 6-MP-CNPs showed improved bioavailability. Thus, the results of the present study revealed that, the prepared 6-MP-CNPs have a significant role in increasing anti-cancer efficacy, bioavailability and in vivo pharmacokinetics profiles.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  6. Maizura M, Fazilah A, Norziah MH, Karim AA
    J Food Sci, 2007 Aug;72(6):C324-30.
    PMID: 17995673
    Edible films were prepared from a mixture of partially hydrolyzed sago starch and alginate (SA). Lemongrass oil (0.1% to 0.4%, v/w) and glycerol (0% and 20%, w/w) were incorporated in the films to act as natural antimicrobial agent and plasticizer, respectively. The films were characterized for antimicrobial activity, water vapor permeability (WVP), tensile strength (TS), percent elongation at break (%E), and water solubility (WS). Fourier transform infrared (FTIR) spectroscopy was conducted to determine functional group interactions between the matrix and lemongrass oil. The zone of inhibition was increased significantly (P < 0.05) by addition of lemongrass oil at all levels in the presence and the absence of glycerol. This indicates that the film containing lemongrass oil was effective against Escherichia coli O157:H7 at all levels. In the absence of glycerol, the tensile strength of film decreased as the oil content increased, but there was no significant (P > 0.05) difference in percent elongation. The percent elongation at break and WVP values for film with 20% glycerol was found to be increased significantly (P < 0.05) with an increase in lemongrass oil content. Addition of lemongrass oil did not have any interaction with the functional groups of films as measured by FTIR.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  7. Katas H, Lim CS, Nor Azlan AYH, Buang F, Mh Busra MF
    Saudi Pharm J, 2019 Feb;27(2):283-292.
    PMID: 30766441 DOI: 10.1016/j.jsps.2018.11.010
    A simple, cost-effective, and environmentally friendly method is needed for synthesizing metal nanoparticles, including gold nanoparticles (AuNPs). In this study, AuNPs were synthesized with Lignosus rhinocerotis sclerotial extract (LRE) and chitosan (CS) as reducing and stabilizing agents, respectively. Different LRE concentrations from cold and hot water extraction (CWE and HWE, respectively) were used to reduce chloroauric acid (HAuCl4) to form AuNPs. Positively charged chitosan stabilized AuNPs (CS-AuNPs) mediated by LRE exhibited a surface plasmon resonance (SPR) band at 533 nm. The CS-AuNPs synthesized using CWE had a smaller particle size (49.5 ± 6.7-82.4 ± 28.0 nm) compared to that of the HWE samples (80.3 ± 23.4-125.3 ± 41.5 nm), depending on LRE concentration. FTIR results suggested protein and polysaccharides in LRE were the sources of reducing power, reducing gold ions to AuNPs. CS-AuNPs were mostly spherical with higher LRE concentrations, whereas some triangular, pentagonal, irregular, and rod shaped AuNPs were observed at lower LRE concentrations. CS-AuNPs mediated by LRE displayed effective antibacterial activity against gram-negative (Pseudomonas aeruginosa and Escherichia coli) and gram-positive bacteria (Staphylococcus aureus and Bacillus sp.). Thus, the biosynthesized AuNPs using LRE and chitosan provide opportunities for developing stable and eco-friendly nanoparticles with effective antibacterial properties.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  8. Ismail NA, Shameli K, Wong MM, Teow SY, Chew J, Sukri SNAM
    Mater Sci Eng C Mater Biol Appl, 2019 Nov;104:109899.
    PMID: 31499959 DOI: 10.1016/j.msec.2019.109899
    In this study, a comparative study of effect using honey on copper nanoparticles (Cu-NPs) via simple, environmentally friendly process and inexpensive route was reported. Honey and ascorbic acid act as stabilizing and reducing agents with the assistance of sonochemical method. The products were characterized using UV-visible (UV-vis) spectroscopy, X-Ray Diffraction (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), Field-Emission Scanning Electron Microscopy (FESEM) and Fourier Transform Infrared (FTIR) spectroscopy. The reddish brown colour demonstrated the formation of Cu-NPs and UV-visible proved the plasmon resonance of Cu-NPs. XRD also confirmed a highly pure Cu-NPs obtained with absence of copper oxide in which the structure is crystalline. The spherical size of the Cu-NPs was acquire in the presence of honey which is 3.68 ± 0.78 nm with narrow particle distribution. The antibacterial activity was seen against gram-positive and gram-negative bacteria which are Enterococcus faecalis (E. faecalis) and Escherichia coli (E. coli). At higher concentration of Cu-NPs, they were more effective in killing both bacteria. The Cu-NPs without and with honey exhibited toxicities toward normal and cancerous cells. However, Cu-NPs without honey showed more potent killing activity against normal and cancer cells.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  9. Xu FX, Ooi CW, Liu BL, Song CP, Chiu CY, Wang CY, et al.
    Int J Biol Macromol, 2021 Jun 30;181:508-520.
    PMID: 33775766 DOI: 10.1016/j.ijbiomac.2021.03.151
    This study aimed to develop a novel electrospun polyacrylonitrile (PAN) nanofiber membrane with the enhanced antibacterial property. The PAN nanofiber membrane was first subjected to alkaline hydrolysis treatment, and the treated membrane was subsequently grafted with chitosan (CS) to obtain a CS-modified nanofiber membrane (P-COOH-CS). The modified membrane was then coupled with different dye molecules to form P-COOH-CS-Dye membranes. Lastly, poly(hexamethylene biguanide) hydrochloride (PHMB) was immobilized on the modified membrane to produce P-COOH-CS-Dye-PHMB. Physical characterization studies were conducted on all the synthesized nanofiber membranes. The antibacterial efficacies of nanofiber membranes prepared under different synthesis conditions were evaluated systematically. Under the optimum synthesis conditions, P-COOH-CS-Dye-PHMB was highly effective in disinfecting a high concentration of Escherichia coli, with an antibacterial efficacy of approximately 100%. Additionally, the P-COOH-CS-Dye-PHMB exhibited an outstanding wash durability as its antibacterial efficacy was only reduced in the range of 5%-7% even after 5 repeated cycles of treatment. Overall, the experimental results of this study suggested that the P-COOH-CS-Dye-PHMB is a promising antibacterial nanofiber membrane that can be adopted in the food, pharmaceutical, and textile industries.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  10. Yahya MFZR, Alias Z, Karsani SA
    Folia Microbiol (Praha), 2018 Jan;63(1):23-30.
    PMID: 28540585 DOI: 10.1007/s12223-017-0532-9
    Biofilms are complex microbial communities that tend to attach to either biotic or abiotic surface. Enclosed in a self-produced extracellular polymeric substance (EPS) matrix, the biofilms often cause persistent infections. The objective of this study was to investigate the antibiofilm activity of dimethyl sulfoxide (DMSO) and afatinib against Gram-negative pathogens. Test microorganisms used in this study were Escherichia coli ATCC 1299, Pseudomonas aeruginosa ATCC 10145, and Salmonella typhimurium ATCC 14028. Biofilms were developed in 96-well microplate at 37°C for 24 h. Following removal of non-adherent cells, analysis of biofilm viability, biofilm biomass, and extracellular polymeric substances (EPS) matrix were performed using resazurin assay, crystal violet assay, and attenuated total reflectance fourier transform infrared (ATR-FTIR) spectroscopy, respectively. Bradford protein assay was conducted to determine the total amount of EPS proteins. The results demonstrated that both 32% DMSO alone and its combination with 3.2 μg/mL afatinib were effective in killing biofilm cells and reducing biofilm biomass. IR spectral variations of EPS matrix of biofilms in the range between 1700 and 900 cm-1 were also observed. Reduction in EPS proteins verified the chemical modifications of EPS matrix. In conclusion, 32% DMSO alone and its combination with 3.2 μg/mL afatinib showed remarkable antibiofilm activities against Gram-negative pathogens. It was suggested that the biofilm inhibition was mediated by the chemical modification of EPS matrix.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  11. Azadi S, Azizipour E, Amani AM, Vaez A, Zareshahrabadi Z, Abbaspour A, et al.
    Sci Rep, 2024 Mar 11;14(1):5855.
    PMID: 38467729 DOI: 10.1038/s41598-024-56512-5
    The antifungal efficacy and cytotoxicity of a novel nano-antifungal agent, the Fe3O4@SiO2/Schiff-base complex of Cu(II) magnetic nanoparticles (MNPs), have been assessed for targeting drug-resistant Candida species. Due to the rising issue of fungal infections, especially candidiasis, and resistance to traditional antifungals, there is an urgent need for new therapeutic strategies. Utilizing Schiff-base ligands known for their broad-spectrum antimicrobial activity, the Fe3O4@SiO2/Schiff-base/Cu(II) MNPs have been synthesized. The Fe3O4@SiO2/Schiff-base/Cu(II) MNPs was characterized by Fourier Transform-Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Energy-dispersive X-ray (EDX), Vibrating Sample Magnetometer (VSM), and Thermogravimetric analysis (TGA), demonstrating successful synthesis. The antifungal potential was evaluated against six Candida species (C. dubliniensis, C. krusei, C. tropicalis, C. parapsilosis, C. glabrata, and C. albicans) using the broth microdilution method. The results indicated strong antifungal activity in the range of 8-64 μg/mL with the lowest MIC (8 μg/mL) observed against C. parapsilosis. The result showed the MIC of 32 μg/mL against C. albicans as the most common infection source. The antifungal mechanism is likely due to the disruption of the fungal cell wall and membrane, along with increased reactive oxygen species (ROS) generation leading to cell death. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay for cytotoxicity on mouse L929 fibroblastic cells suggested low toxicity and even enhanced cell proliferation at certain concentrations. This study demonstrates the promise of Fe3O4@SiO2/Schiff-base/Cu(II) MNPs as a potent antifungal agent with potential applications in the treatment of life-threatening fungal infections, healthcare-associated infections, and beyond.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  12. Tevan, R., Govindaraju, Mugilan, Jayakumar, Saravanan, Govindan, Natanamurugaraj, Mohd Hasbi Ab. Rahim, Maniam, Gaanty Pragas, et al.
    MyJurnal
    A biological method was employed to synthesize silver nanoparticles through marine diatom Amphora sp. Antimicrobial efficacy test against different pathogenic bacteria were performed through synthesized silver nanoparticles. The physio-chemical properties of synthesized silver nanoparticles were studied using analytical techniques such as UV-Vis spectrophotometer, Field Emission Scanning Electron Microscopy (FESEM), EnergyDispersive X-ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Powder Diffraction (XRD). UV-Vis color intensity study and higher magnification of the Field Emission Scanning Electron Microscopy image showed the synthesized silver nanoparticles were rod shaped with a size range from 42 nm to 46 nm. The synthesized nanoparticles exhibited antibacterial activities in varying magnitudes. About 10 mg/ml of silver nanoparticles were able to inhibit the growth of gram-negative bacteria while gram-positive bacteria were resistant towards similar concentrations of silver nanoparticles.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  13. Mishra RK, Ramasamy K, Lim SM, Ismail MF, Majeed AB
    J Mater Sci Mater Med, 2014 Aug;25(8):1925-39.
    PMID: 24831081 DOI: 10.1007/s10856-014-5228-y
    The present study investigates the development of methyl cellulose (MC)-sodium alginate (SA)-montmorillonite (MMT) clay based bionanocomposite films with interesting wound healing properties. The differential scanning calorimetry analysis of the composite films revealed presence of single glass transition temperature (Tg) confirming the miscible nature of the ternary blended films. The increase in MMT ratio in the composite films reduced the mobility of biopolymer chains (MC/SA) which increased the Tg of the film. Thermogravimetric analysis showed that dispersion of clay (MMT) at nano level significantly delayed the weight loss that correlated with higher thermal stability of the composite films. It was observed that the developed films were able to exhibit antimicrobial activity against four typical pathogenic bacteria found in the presence of wound. The developed films were able to significantly inhibit (10 mg/ml) the growth of Enterococcus faecium and Pseudomonas aeruginosa. In vitro scratch assay indicated potential wound closure activities of MC-2-4 bionanocomposite films at their respective highest subtoxic doses. In conclusion, these ternary bionanocomposite films were found to be promising systems for wound healing applications.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  14. Dhand C, Balakrishnan Y, Ong ST, Dwivedi N, Venugopal JR, Harini S, et al.
    Int J Nanomedicine, 2018;13:4473-4492.
    PMID: 30122921 DOI: 10.2147/IJN.S159770
    Introduction: In search for cross-linkers with multifunctional characteristics, the present work investigated the utility of quaternary ammonium organosilane (QOS) as a potential cross-linker for electrospun collagen nanofibers. We hypothesized that the quaternary ammonium ions improve the electrospinnability by reducing the surface tension and confer antimicrobial properties, while the formation of siloxane after alkaline hydrolysis could cross-link collagen and stimulate cell proliferation.

    Materials and methods: QOS collagen nanofibers were electrospun by incorporating various concentrations of QOS (0.1%-10% w/w) and were cross-linked in situ after exposure to ammonium carbonate. The QOS cross-linked scaffolds were characterized and their biological properties were evaluated in terms of their biocompatibility, cellular adhesion and metabolic activity for primary human dermal fibroblasts and human fetal osteoblasts.

    Results and discussion: The study revealed that 1) QOS cross-linking increased the flexibility of otherwise rigid collagen nanofibers and improved the thermal stability; 2) QOS cross-linked mats displayed potent antibacterial activity and 3) the biocompatibility of the composite mats depended on the amount of QOS present in dope solution - at low QOS concentrations (0.1% w/w), the mats promoted mammalian cell proliferation and growth, whereas at higher QOS concentrations, cytotoxic effect was observed.

    Conclusion: This study demonstrates that QOS cross-linked mats possess anti-infective properties and confer niches for cellular growth and proliferation, thus offering a useful approach, which is important for hard and soft tissue engineering and regenerative medicine.

    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  15. Al-Majedy YK, Al-Amiery AA, Kadhum AA, Mohamad AB
    PLoS One, 2016;11(5):e0156625.
    PMID: 27243231 DOI: 10.1371/journal.pone.0156625
    The synthesis of derivatives of 4-Methylumbelliferone (4-MUs), which are structurally interesting antioxidants, was performed in this study. The modification of 4-Methylumbelliferone (4-MU) by different reaction steps was performed to yield the target compounds, the 4-MUs. The 4-MUs were characterized by different spectroscopic techniques (Fourier transform infrared; FT-IR and Nuclear magnetic resonance; NMR) and micro-elemental analysis (CHNS). The in vitro antioxidant activity of the 4-MUs was evaluated in terms of their free radical scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH), Nitric oxide radical scavenging activity assay, chelating activity and their (FRAP) ferric-reducing antioxidant power, which were compared with a standard antioxidant. Our results reveal that the 4-MUs exhibit excellent radical scavenging activities. The antioxidant mechanisms of the 4-MUs were also studied. Density Function Theory (DFT)-based quantum chemical studies were performed with the basis set at 3-21G. Molecular models of the synthesized compounds were studied to understand the antioxidant activity. The electron levels, namely HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital), for these synthesized antioxidants were also studied.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  16. Saifullah B, Hussein MZ, Hussein-Al-Ali SH, Arulselvan P, Fakurazi S
    Drug Des Devel Ther, 2013;7:1365-75.
    PMID: 24255593 DOI: 10.2147/DDDT.S50665
    We report the intercalation and characterization of para-amino salicylic acid (PASA) into zinc/aluminum-layered double hydroxides (ZLDHs) by two methods, direct and indirect, to form nanocomposites: PASA nanocomposite prepared by a direct method (PASA-D) and PASA nanocomposite prepared by an indirect method (PASA-I). Powder X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis revealed that the PASA drugs were accommodated within the ZLDH interlayers. The anions of the drug were accommodated as an alternate monolayer (along the long-axis orientation) between ZLDH interlayers. Drug loading was estimated to be 22.8% and 16.6% for PASA-D and PASA-I, respectively. The in vitro release properties of the drug were investigated in physiological simulated phosphate-buffered saline solution of pH 7.4 and 4.8. The release followed the pseudo-second-order model for both nanocomposites. Cell viability (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide [MTT] assays) was assessed against normal human lung fibroblast MRC-5 and 3T3 mouse fibroblast cells at 24, 48, and 72 hours. The results showed that the nanocomposite formulations did not possess any cytotoxicity, at least up to 72 hours.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  17. Mengting Z, Kurniawan TA, Fei S, Ouyang T, Othman MHD, Rezakazemi M, et al.
    Environ Pollut, 2019 Dec;255(Pt 1):113182.
    PMID: 31541840 DOI: 10.1016/j.envpol.2019.113182
    Methylene blue (MB) is a dye pollutant commonly present in textile wastewater. We investigate and critically evaluate the applicability of BaTiO3/GO composite for photodegradation of MB in synthetic wastewater under UV-vis irradiation. To enhance its performance, the BaTiO3/GO composite is varied based on the BaTiO3 weight. To compare and evaluate any changes in their morphologies and crystalline structures before and after treatment, BET (Brunauer-Emmett-Teller), XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy) and TEM (transmission electron microscopy) tests are conducted, while the effects of reaction time, pH, dose of photocatalyst and initial MB concentration on its photodegradation by the composite are also investigated under identical conditions. The degradation pathways and removal mechanisms of MB by the BaTiO3/GO are elaborated. It is evident from this study that the BaTiO3/GO composite is promising for MB photodegradation through ·OH. Under optimized conditions (0.5 g/L of dose, pH 9.0, and 5 mg/L of MB concentration), the composite with 1:2 dose ratio of BaTiO3/GO has the highest MB degradation rate (95%) after 3 h of UV vis irradiation. However, its treated effluents still could not comply with the discharge standard limit of less than 0.2 mg/L imposed by national environmental legislation. This suggests that additional biological treatments are still required to deal with the remaining oxidation by-products of MB, still present in the wastewater samples such as 3,7-bis (dimethyl-amino)-10H-phenothiazine 5-oxide.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  18. Xu D, Gao Y, Lin Z, Gao W, Zhang H, Karnowo K, et al.
    Front Chem, 2019;7:943.
    PMID: 32117859 DOI: 10.3389/fchem.2019.00943
    In this study, biochars derived from waste fiberboard biomass were applied in tetracycline (TC) removal in aqueous solution. Biochar samples were prepared by slow pyrolysis at 300, 500, and 800°C, and were characterized by ultimate analysis, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), etc. The effects of ionic strength (0-1.0 mol/L of NaCl), initial TC concentration (2.5-60 ppm), biochar dosage (1.5-2.5 g/L), and initial pH (2-10) were systemically determined. The results present that biochar prepared at 800°C (BC800) generally possesses the highest aromatization degree and surface area with abundant pyridinic N (N-6) and accordingly shows a better removal efficiency (68.6%) than the other two biochar samples. Adsorption isotherm data were better fitted by the Freundlich model (R2 is 0.94) than the Langmuir model (R2 is 0.85). Thermodynamic study showed that the adsorption process is endothermic and mainly physical in nature with the values of ΔH0 being 48.0 kJ/mol, ΔS0 being 157.1 J/mol/K, and ΔG0 varying from 1.02 to -2.14 kJ/mol. The graphite-like structure in biochar enables the π-π interactions with a ring structure in the TC molecule, which, together with the N-6 acting as electron donor, is the main driving force of the adsorption process.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  19. Van Tran T, Nguyen DTC, Nguyen HT, Nanda S, Vo DN, Do ST, et al.
    Environ Sci Pollut Res Int, 2019 Sep;26(27):28106-28126.
    PMID: 31363978 DOI: 10.1007/s11356-019-06011-2
    The occurrence and fate of antibiotic compounds in water can adversely affect human and animal health; hence, the removal of such substrates from soil and water is indispensable. Herein, we described the synthesis method of mesoporous carbon (MPC) via the pyrolysis route from a coordination polymer Fe-based MIL-53 (or MIL-53, shortly). The MPC structure was analyzed by several physical techniques such as SEM, TEM, BET, FT-IR, VSM, and XRD. The response surface methodology (RSM) was applied to find out the effects of initial concentration, MPC dosage, and pH on the removal efficiency of trimethoprim (TMP) and sulfamethoxazole (SMX) antibiotics in water. Under the optimized conditions, the removal efficiencies of TMP and SMX were found to be 87% and 99%, respectively. Moreover, the adsorption kinetic and isotherm studies showed that chemisorption and the monolayer adsorption controlled the adsorption process. The leaching test and recyclability studies indicated that the MPC structure was stable and can be reused for at least four times without any considerable change in the removal efficiency. Plausible adsorption mechanisms were also addressed in this study. Because of high maximum adsorption capacity (85.5 mg/g and 131.6 mg/g for TMP and SMX, respectively) and efficient reusability, MPC is recommended to be a potential adsorbent for TMP and SMX from water media.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
  20. Mukhopadhyay S, Mukherjee S, Hashim MA, Sen Gupta B
    Chemosphere, 2015 Jan;119:355-362.
    PMID: 25061940 DOI: 10.1016/j.chemosphere.2014.06.087
    Colloidal gas aphron dispersions (CGAs) can be described as a system of microbubbles suspended homogenously in a liquid matrix. This work examines the performance of CGAs in comparison to surfactant solutions for washing low levels of arsenic from an iron rich soil. Sodium Dodecyl Sulfate (SDS) and saponin, a biodegradable surfactant, obtained from Sapindus mukorossi or soapnut fruit were used for generating CGAs and solutions for soil washing. Column washing experiments were performed in down-flow and up flow modes at a soil pH of 5 and 6 using varying concentration of SDS and soapnut solutions as well as CGAs. Soapnut CGAs removed more than 70% arsenic while SDS CGAs removed up to 55% arsenic from the soil columns in the soil pH range of 5-6. CGAs and solutions showed comparable performances in all the cases. CGAs were more economical since it contains 35% of air by volume, thereby requiring less surfactant. Micellar solubilization and low pH of soapnut facilitated arsenic desorption from soil column. FT-IR analysis of effluent suggested that soapnut solution did not interact chemically with arsenic thereby facilitating the recovery of soapnut solution by precipitating the arsenic. Damage to soil was minimal arsenic confirmed by metal dissolution from soil surface and SEM micrograph.
    Matched MeSH terms: Spectroscopy, Fourier Transform Infrared
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