Displaying publications 2621 - 2640 of 10390 in total

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  1. Amin F, Khan S, Shah SMH, Rahim H, Hussain Z, Sohail M, et al.
    Drug Des Devel Ther, 2018;12:3855-3866.
    PMID: 30510401 DOI: 10.2147/DDDT.S183534
    Background: The obnoxious bitter taste of orally taken antibiotics is one of the biggest problems in the treatment of children. The pediatric population cannot tolerate the bitter taste of drugs and vomit out which ultimately leads to suboptimal therapeutic value, grimace and mental stress so it is the challenging task for the formulation scientists to formulate a palatable formulation particularly to overcome address the issue.

    Purpose of study: The study aimed to mask and evaluate the unpleasant bitter taste of azithro-mycin (AZ) in the dry suspension dosage form by physisorption technique.

    Materials and methods: AZ was selected as an adsorbent and titanium dioxide nanoparticles as adsorbate. The AZ nanohybrids (AZN) were prepared by treating fixed amount of adsorbent with a varied amount of adsorbate, prepared separately by dispersing it in an aqueous medium. The mixture was sonicated, stirred followed by filtration and drying. The AZN produced were characterized by various techniques including scanning electron microscopy (SEM), energy dispersive X-rays (EDX), powder X-ray diffraction (PXRD), HPLC and Fourier-transformed infrared (FTIR). The optimized nanohybrid was blended with other excipients to get stable and taste masked dry suspension dosage form.

    Results: The results confirmed the adsorption of titanium dioxide nanoparticles on the surface of AZ. The fabricated optimized formulation was subjected for taste masking by panel testing and accelerated stability studies. The results showed a remarkable improvement in bitter taste masking, inhibiting throat bite without affecting the dissolution rate. The product showed an excellent stability both in dry and reconstituted suspension. The optimized formulation of AZN and was found stable when subjected to physical and chemical stability studies, this is because of short and single step process which interns limits the exposure of the product to various environmental factors that could potentially affect the stability of the product. The dissolution rate of the optimized formulation of AZN was compared with its marketed counterpart, showing the same dissolution rate compared to its marketed formulation.

    Conclusion: The current study concludes that, by fabricating AZ-titanium nanohybrids using physisorption can effectively mask the bitter taste of the drug. The palatability and stability of azithromycin formulation was potentially enhanced without affecting its dissolution rate.

    Matched MeSH terms: Anti-Bacterial Agents/chemistry; Titanium/chemistry; Azithromycin/chemistry; Nanoparticles/chemistry*
  2. Garba J, Samsuri AW, Othman R, Ahmad Hamdani MS
    Environ Monit Assess, 2018 Oct 27;190(11):676.
    PMID: 30368595 DOI: 10.1007/s10661-018-7034-3
    This study investigates adsorption-desorption and the leaching potential of glyphosate and aminomethylphosphonic acid (AMPA) in control and amended-addition of cow dung or rice husk ash-acidic Malaysian soil with high oxide mineral content. The addition of cow dung or rice husk ash increased the adsorptive removal of AMPA. The isotherm data of glyphosate and AMPA best fitted the Freundlich model. The constant Kf for glyphosate was high in the control soil (544.873 mg g-1) followed by soil with cow dung (482.451 mg g-1) then soil with rice husk ash (418.539 mg g-1). However, for AMPA, soil with cow dung was high (166.636 mg g-1) followed by soil with rice husk ash (137.570 mg g-1) then the control soil (48.446 mg g-1). The 1/n values for both glyphosate and AMPA adsorptions were
    Matched MeSH terms: Glycine/chemistry; Isoxazoles/chemistry*; Soil/chemistry*; Tetrazoles/chemistry*
  3. Nordin N, Ho LN, Ong SA, Ibrahim AH, Abdul Rani AL, Lee SL, et al.
    Chemosphere, 2020 Apr;244:125459.
    PMID: 31790991 DOI: 10.1016/j.chemosphere.2019.125459
    The hybrid electrochemical system of photocatalytic fuel cell - peroxi-coagulation (PFC-PC) is a combined technology of advanced oxidation process (AOP) which involve the hydroxyl radical formation for simultaneous degradation of organic pollutant and electricity generation. The p-nitrosodimethylaniline (RNO) spin trapping technique was applied by analyzing the RNO bleaching performance to detect the OH at the PFC and PC reactors. The presence of UV light showed higher RNO bleaching rate at the PFC reactor (11.7%) with maximum power density (Pmax = 3.14 mW cm-2). Results revealed that the optimum of maximum power density was observed at iron plate size of 30 cm2. UV light became a limiting factor in the PFC system as a power source in the PFC-PC system. Meanwhile, iron plate plays an important role to supply the soluble Fe2+ ions by oxidation process and become a suitable catalyst for in-situ production of H2O2 and OH through the PC process to degrade the organic molecules.
    Matched MeSH terms: Hydrogen Peroxide/chemistry; Iron/chemistry; Water Pollutants, Chemical/chemistry*; Hydroxyl Radical/chemistry*
  4. Rajapakse S, de Silva NL, Weeratunga P, Rodrigo C, Sigera C, Fernando SD
    BMC Complement Altern Med, 2019 Oct 11;19(1):265.
    PMID: 31601215 DOI: 10.1186/s12906-019-2678-2
    BACKGROUND: Carica papaya (CP) extract is becoming popular as an unlicensed herbal remedy purported to hasten recovery in dengue infection, mostly based on observations that it may increase platelet counts. This systematic review and meta-analysis aims to critically analyze the evidence from controlled clinical trials on the efficacy and safety of CP extract in the treatment of dengue infection.

    METHODS: PubMed, LILACS and Google Scholar were searched for randomized or non-randomized trials enrolling patients with suspected or confirmed dengue where CP extract was compared, as a treatment measure, against standard treatment. Recovery of platelet counts as well as other clinical indicators of favourable outcome (duration of hospital stay, prevention of plasma leakage, life threatening complications, and mortality) were assessed.

    RESULTS: Nine studies (India-6, Pakistan-1, Indonesia-1, Malaysia-1) met the inclusion criteria. Seven studies showed an increase in platelet counts in patients receiving CP extract, while one study showed no significant difference between the two groups, and direct comparison was not possible in the remaining study. Serious adverse events were not reported. CP extract may reduce the duration of hospital stay (mean difference - 1.98 days, 95% confidence interval - 1.83 to - 2.12, 3 studies, 580 participants, low quality evidence), and cause improvement in mean platelet counts between the first and fifth day of treatment (mean difference 35.45, 95% confidence interval 23.74 to 47.15, 3 studies, 129 participants, low quality evidence). No evidence was available regarding other clinical outcomes.

    CONCLUSIONS: The clinical value of improvement in platelet count or early discharge is unclear in the absence of more robust indicators of favourable clinical outcome. Current evidence is insufficient to comment on the role of CP extract in dengue. There is a need for further well designed clinical trials examining the effect of CP on platelet counts, plasma leakage, other serious manifestations of dengue, and mortality, with clearly defined outcome measures.

    Matched MeSH terms: Antiviral Agents/chemistry; Plant Extracts/chemistry; Plant Leaves/chemistry; Carica/chemistry*
  5. Agi A, Junin R, Arsad A, Abbas A, Gbadamosi A, Azli NB, et al.
    Int J Biol Macromol, 2020 Apr 01;148:1251-1271.
    PMID: 31760018 DOI: 10.1016/j.ijbiomac.2019.10.099
    Ascorbic acid was used for the first time to synthesize crystalline starch nanoparticles (CSNP). The physical properties of the CSNP were investigated. Rheological properties of the crystalline starch nanofluid (CSNF) were compared with native cassava starch (CS) and commercial polymer xanthan. Interfacial properties of the CSNF at the interface of oil and water (O/W) were investigated at different concentrations and temperatures. Wettability alteration efficiency of CSNF on oil-wet sandstone surface was investigated using the sessile drop method. Core flooding experiment was conducted at reservoir conditions. The methods were effective in producing spherical and polygonal nanoparticles with a mean diameter of 100 nm and increased in crystallinity of 7%. Viscosity increased with increase in surface area and temperature of the CSNF compared to a decrease in viscosity as the temperature increases for xanthan. Interfacial tension (IFT) decreased with increase in concentration of CSNF, electrolyte and temperature. The results show that CSNF can change the wettability of sandstone at low concentration, high salinity and elevated temperature. Pressure drops data shows stability of CSNF at 120 °C. The formation of oil bank was enough to increase oil recovery by 23%.
    Matched MeSH terms: Acids/chemistry*; Oils/chemistry*; Starch/chemistry*; Nanoparticles/chemistry*
  6. Choudhury H, Maheshwari R, Pandey M, Tekade M, Gorain B, Tekade RK
    Mater Sci Eng C Mater Biol Appl, 2020 Jan;106:110275.
    PMID: 31753398 DOI: 10.1016/j.msec.2019.110275
    Etoposide (ETS), topoisomerase-II inhibitor, is a first-line anticancer therapeutics used in diverse cancer types. However, the therapeutic potential of this molecule has mainly impeded due to its detrimental toxicity profile, unfavorable rejection by the cancer cells due to P-glycoprotein (P-gp) efflux activity, and rapid hepatic clearance through extensive metabolism by Cytochrome-P450. To increase the therapeutic potency without significant adverse effects, the implication of novel ETS-nanoformulation strategies have recommended mainly. Nanomedicine based nanoformulation approaches based on nanoparticles (NPs), dendrimers, carbon-nanotubes (CNTs), liposomes, polymeric micelles, emulsions, dendrimers, solid-lipid NPs, etc offers immense potential opportunities to improve the therapeutic potential of pharmaceutically problematic drugs. This review provides an up-to-date argument on the work done in the field of nanomedicine to resolve pharmacokinetic and pharmacodynamic issues associated with ETS. The review also expounds the progress in regards to the regulatory, patenting and clinical trials related to the innovative formulation aspects of ETS.
    Matched MeSH terms: Drug Carriers/chemistry*; Etoposide/chemistry*; Nanoparticles/chemistry*; Topoisomerase II Inhibitors/chemistry*
  7. Khalivulla SI, Mohammed A, Sirajudeen KNS, Shaik MI, Ye W, Korivi M
    Curr Drug Metab, 2019;20(12):946-957.
    PMID: 31744445 DOI: 10.2174/1389200220666191118102616
    BACKGROUND: Typhonium is the largest genus in the Araceae family (~70 species), distributed in South Asia, Southeast Asia and Australia. Typhonium is well-known for its ethnopharmacological uses, and Southeast Asians consider it as an alternative medicine to treat cancer. This review elucidated the confirmed chemical structures of the isolated compounds of Typhonium and emphasized on their anticancer activities against various human cancer cells.

    METHODS: Among several species, Typhonium blumei, T. flagelliforme, T. divaricatum and T. giganteum were extensively studied due to the presence of a class of secondary metabolites. All the available reports on Typhonium were included and discussed in this article.

    RESULTS: Until now several groups of compounds, namely amino acids (1, 2), cinnamic acid (3), fatty acids (4-14), glycerol derivatives (15-18) and cerebrosides (19-34), flavonoids (35), hydantoins (36-38), lignin monomers (39-44), nucleobases (45-48), pheophorbides (49-52), phthalate (53), terpene and steroids (54-59) and vitamins (60, 61) were isolated and characterized from Typhonium. These phytochemicals were investigated for their anticancer properties, and results confirmed the promising growth inhibitory effect and anticancer activities against human lung, breast, prostate and colon cancer cells. The anticancer activity of these compounds appears to be mediated through the induction of apoptotic cell death. These phytochemicals further reported to exhibit other pharmacological efficacies, including anti-inflammatory, antioxidant, antiviral, anti-allergic, neuroprotective and hepato-protective properties.

    CONCLUSION: This is the first review to summarize the anticancer properties of all isolated compounds of Typhonium genus with confirmed chemical structures. Further advanced studies are necessary to establish the detailed signaling pathways that are involved in the anticancer property of the compounds.

    Matched MeSH terms: Antineoplastic Agents, Phytogenic/chemistry*; Plant Extracts/chemistry*; Araceae/chemistry*; Phytochemicals/chemistry*
  8. Jajuli MN, Hussin MH, Saad B, Rahim AA, Hébrant M, Herzog G
    Anal Chem, 2019 06 04;91(11):7466-7473.
    PMID: 31050400 DOI: 10.1021/acs.analchem.9b01674
    A new sample preparation method is proposed for the extraction of pharmaceutical compounds (Metformin, Phenyl biguanide, and Phenformin) of varied hydrophilicity, dissolved in an aqueous sample. When in contact with an organic phase, an interfacial potential is imposed by the presence of an ion, tetramethylammonium (TMA+), common to each phase. The interfacial potential difference drives the transfer of ionic analytes across the interface and allows it to reach up to nearly 100% extraction efficiency and a 60-fold enrichment factor in optimized extraction conditions as determined by HPLC analysis.
    Matched MeSH terms: Quaternary Ammonium Compounds/chemistry; Biguanides/chemistry; Metformin/chemistry; Phenformin/chemistry
  9. Hassandoost R, Pouran SR, Khataee A, Orooji Y, Joo SW
    J Hazard Mater, 2019 08 15;376:200-211.
    PMID: 31128399 DOI: 10.1016/j.jhazmat.2019.05.035
    The main prerequisite of an active visible-light-driven photocatalyst is to effectively utilize the visible light to induce electron-hole (e-/h+) pairs of expanded lifetime. To this end, for the first time, the ternary heterojunctions of CeO2/Fe3O4 /Graphene oxide and Ce3+/ Fe3O4 /Graphene oxide (CeO2/Fe3O4/GO and Fe2.8Ce0.2O4/GO) were prepared via facile ultrasonic-assisted procedures and employed for destruction of oxytetracycline (OTC) under visible light irradiation. The changes in the relative crystal structure, morphology, atomic and surface functional group composition, magnetic, and optic properties of magnetite were uncovered by various techniques. The substantial degradation and mineralization of OTC via visible light/Fe2.8Ce0.2O4/GO system were thoroughly discussed in terms of narrowed band gap energy, the principal function of Ce3+/Ce4+ and Fe2+/Fe3+ redox pairs and GO platelets, enhanced charge separation and transfer, and enlarged active surface area. Furthermore, the performance of visible light/Fe2.8Ce0.2O4/GO system was evaluated for treating real wastewater and its efficiency was investigated using a number of enhancers and scavengers. Finally, the generated byproducts in the course of photodegradation were determined and the oxidation pathway, photocatalytic kinetics, and plausible mechanism were proposed. The results confirmed that the introduced Ce ions and graphene oxide sheets boost the photo-catalytic efficiency of magnetite for photodegradation of OTC.
    Matched MeSH terms: Cerium/chemistry*; Graphite/chemistry*; Nanocomposites/chemistry*; Magnetite Nanoparticles/chemistry*
  10. Tan HL, Kai D, Pasbakhsh P, Teow SY, Lim YY, Pushpamalar J
    Colloids Surf B Biointerfaces, 2020 Apr;188:110713.
    PMID: 31884080 DOI: 10.1016/j.colsurfb.2019.110713
    Electrospinning is a common method to prepare nanofiber scaffolds for tissue engineering. One of the common cellulose esters, cellulose acetate butyrate (CAB), has been electrospun into nanofibers and studied. However, the intrinsic hydrophobicity of CAB limits its application in tissue engineering as it retards cell adhesion. In this study, the properties of CAB nanofibers were improved by fabricating the composite nanofibers made of CAB and hydrophilic polyethylene glycol (PEG). Different ratios of CAB to PEG were tested and only the ratio of 2:1 resulted in smooth and bead-free nanofibers. The tensile test results show that CAB/PEG composite nanofibers have 2-fold higher tensile strength than pure CAB nanofibers. The hydrophobicity of the composite nanofibers was also reduced based on the water contact angle analysis. As the hydrophilicity increases, the swelling ability of the composite nanofiber increases by 2-fold with more rapid biodegradation. The biocompatibility of the nanofibers was tested with normal human dermal fibroblasts (NHDF). The cell viability assay results revealed that the nanofibers are non-toxic. In addition to that, CAB/PEG nanofibers have better cell attachment compared to pure CAB nanofibers. Based on this study, CAB/PEG composite nanofibers could potentially be used as a nanofiber scaffold for applications in tissue engineering.
    Matched MeSH terms: Biocompatible Materials/chemistry*; Cellulose/chemistry; Polyethylene Glycols/chemistry*; Nanofibers/chemistry*
  11. Abdullah AM, Mohamad D, Rahim TNAT, Akil HM, Rajion ZA
    Mater Sci Eng C Mater Biol Appl, 2019 Jun;99:719-725.
    PMID: 30889745 DOI: 10.1016/j.msec.2019.02.007
    This study reports the influence of ZrO2/β-TCP hybridization on the thermal, mechanical, and physical properties of polyamide 12 composites to be suited for bone replacement. Amount of 15 wt% of nano-ZrO2 along with 5,10,15,20 and 25 wt% of micro-β-TCP was compounded with polyamide 12 via a twin-screw extruder. The hybrid ZrO2/β-TCP filled polyamide 12 exhibited higher thermal, mechanical and physical properties in comparison to unfilled polyamide 12 at certain filler loading; which is attributed to the homogenous dispersion of ZrO2/β-TCP fillers particle in polyamide 12 matrix. The hybrid ZrO2/β-TCP filled PA 12 demonstrated an increment of tensile strength by up to 1%, tensile modulus of 38%, flexural strength of 15%, flexural modulus of 45%, and surface roughness value of 93%, as compared to unfilled PA 12. With enhanced thermal, mechanical and physical properties, the newly developed hybrid ZrO2/β-TCP filled PA 12 could be potentially utilized for bone replacement.
    Matched MeSH terms: Calcium Phosphates/chemistry; Ceramics/chemistry*; Nylons/chemistry*; Zirconium/chemistry
  12. Tariq FS, Samsuri AW, Karam DS, Aris AZ, Jamilu G
    Environ Monit Assess, 2019 Mar 21;191(4):232.
    PMID: 30900076 DOI: 10.1007/s10661-019-7359-6
    This study was conducted to determine the effects of rice husk ash (RHA) and Fe-coated rice husk ash (Fe-RHA) on the bioavailability and mobility of As, Cd, and Mn in mine tailings. The amendments were added to the tailings at 0, 5, 10, or 20% (w/w) and the mixtures were incubated for 0, 7, 15, 30, 45, and 60 days. The CaCl2 extractable As, Cd, and Mn in the amended tailings were determined at each interval of incubation period. In addition, the tailings mixture was leached with simulated rain water (SRW) every week from 0 day (D 0) until day 60 (D 60). The results showed that both RHA and Fe-RHA application significantly decreased the CaCl2-extractable Cd and Mn but increased that of As in the tailings throughout the incubation period. Consequently, addition of both RHA and Fe-RHA leached out higher amount of As from the tailings but decreased Cd and Mn concentration compared to the controls. The amount of As leached from the Fe-RHA-amended tailings was less than that from RHA-amended tailings. Application of both RHA and Fe-RHA could be an effective way in decreasing the availability of cationic heavy metals (Cd and Mn) in the tailings but these amendments could result in increasing the availability of anionic metalloid (As). Therefore, selection of organic amendments to remediate metal-contaminated tailings must be done with great care because the outcomes might be different among the elements.
    Matched MeSH terms: Arsenic/chemistry; Cadmium/chemistry; Charcoal/chemistry; Manganese/chemistry
  13. Letchumanan I, Md Arshad MK, Balakrishnan SR, Gopinath SCB
    Biosens Bioelectron, 2019 Apr 01;130:40-47.
    PMID: 30716591 DOI: 10.1016/j.bios.2019.01.042
    This paper primarily demonstrates the approach to enhance the sensing performance on antigen C-reactive protein (CRP) and anti-CRP antibody binding event. A nanogapped electrode structure with the gap of ~100 nm was modified by the anti-CRP antibody (Probe) to capture the available CRP. In order to increase the amount of antigen to be captured, a gold nanorod with 119 nm in length and 25 nm in width was integrated, to increase the surface area. A comparative study between the existence and non-existence of gold nanorod utilization was evaluated. Analysis of the sensing surface was well-supported by atomic force microscopy, scanning electron microscopy, 3D nano-profilometry, high-power microscopy and UV-Vis spectroscopy. The dielectric voltammetric analysis was carried out from 0 V to 2 V. The sensitivity was calculated based on 3σ and attained as low as 1 pM, which is tremendously low compared to real CRP concentration (119 nM) in human blood serum. The gold nanorod conjugation with antibody has enhanced the sensitivity to 100 folds (10 fM). The specificity of the CRP detection by the proposed strategy was anchored by ELISA and failure in the detection of human blood clotting factor IX by voltammetry. Despite, CRP antigen was further detected in human serum by spiking CRP to run-through the detection with the physiologically relevant samples.
    Matched MeSH terms: Antibodies/chemistry; C-Reactive Protein/chemistry; Electrochemistry*; Gold/chemistry; Nanotubes/chemistry
  14. Ghosal K, Das A, Das SK, Mahmood S, Ramadan MAM, Thomas S
    Int J Biol Macromol, 2019 Jun 01;130:645-654.
    PMID: 30797807 DOI: 10.1016/j.ijbiomac.2019.02.117
    This study aimed to develop and characterize the calcium alginate films loaded with diclofenac sodium and other hydrophilic polymers with different degrees of cross-linking obtained by external gelation process. To the formed films different physicochemical evaluation were performed which showed an initial character of the films. The films produced by this external gelation process were found thicker (0.031-0.038 mm) and stronger (51.9-52.9 MPa) but less elastic (2.3%) than those non-cross-linked films (0.029 mm; 39.7 MPa; 4.4%). The lower water vapor permeability (WVP) values of the films were obtained where maximum level of crosslinking occurs. Composite films can be cross-linked in presence of external crosslinking agent to improve the quality of the produced matrices for various uses. The characterization of the film was performed using Differential Scanning Calorimetry (DSC) and Fourier-Transform Infrared Spectroscopy (FT-IR) analysis. The Scanning Electron Microscopy (SEM) study showed the morphology of treated composite films. The kinetic release studies showed a sustained release of the drug from the formulated films as it can be prolonged in composite film. The prepared biodegradable Ca-Alginate bio-composite film may be of clinical importance for its therapeutic benefit.
    Matched MeSH terms: Alginates/chemistry*; Biocompatible Materials/chemistry*; Biopolymers/chemistry*; Drug Carriers/chemistry*
  15. Long CM, Tang K, Chokshi H, Fotaki N
    AAPS PharmSciTech, 2019 Feb 13;20(3):113.
    PMID: 30761437 DOI: 10.1208/s12249-019-1317-z
    The aim of this study is to investigate the dissolution properties of poorly soluble drugs from their pure form and their amorphous formulation under physiological relevant conditions for oral administration based on surface dissolution ultraviolet (UV) imaging. Dissolution of two poorly soluble drugs (cefuroxime axetil and itraconazole) and their amorphous formulations (Zinnat® and Sporanox®) was studied with the Sirius Surface Dissolution Imager (SDI). Media simulating the fasted state conditions (compendial and biorelevant) with sequential media/flow rate change were used. The dissolution mechanism of cefuroxime axetil in simulated gastric fluid (SGF), fasted state simulated gastric fluid (FaSSGF) and simulated intestinal fluid (SIF) is predominantly swelling as opposed to the convective flow in fasted state simulated intestinal fluid (FaSSIF-V1), attributed to the effect of mixed micelles. For the itraconazole compact in biorelevant media, a clear upward diffusion of the dissolved itraconazole into the bulk buffer solution is observed. Dissolution of itraconazole from the Sporanox® compact is affected by the polyethylene glycol (PEG) gelling layer and hydroxypropyl methylcellulose (HPMC) matrix, and a steady diffusional dissolution pattern is revealed. A visual representation and a quantitative assessment of dissolution properties of poorly soluble compounds and their amorphous formulation can be obtained with the use of surface dissolution imaging under in vivo relevant conditions.
    Matched MeSH terms: Anti-Bacterial Agents/chemistry*; Antifungal Agents/chemistry*; Cefuroxime/chemistry; Itraconazole/chemistry*
  16. Ibrahim RK, Fiyadh SS, AlSaadi MA, Hin LS, Mohd NS, Ibrahim S, et al.
    Molecules, 2020 Mar 26;25(7).
    PMID: 32225061 DOI: 10.3390/molecules25071511
    In the recent decade, deep eutectic solvents (DESs) have occupied a strategic place in green chemistry research. This paper discusses the application of DESs as functionalization agents for multi-walled carbon nanotubes (CNTs) to produce novel adsorbents for the removal of 2,4-dichlorophenol (2,4-DCP) from aqueous solution. Also, it focuses on the application of the feedforward backpropagation neural network (FBPNN) technique to predict the adsorption capacity of DES-functionalized CNTs. The optimum adsorption conditions that are required for the maximum removal of 2,4-DCP were determined by studying the impact of the operational parameters (i.e., the solution pH, adsorbent dosage, and contact time) on the adsorption capacity of the produced adsorbents. Two kinetic models were applied to describe the adsorption rate and mechanism. Based on the correlation coefficient (R2) value, the adsorption kinetic data were well defined by the pseudo second-order model. The precision and efficiency of the FBPNN model was approved by calculating four statistical indicators, with the smallest value of the mean square error being 5.01 × 10-5. Moreover, further accuracy checking was implemented through the sensitivity study of the experimental parameters. The competence of the model for prediction of 2,4-DCP removal was confirmed with an R2 of 0.99.
    Matched MeSH terms: Phenols/chemistry*; Solvents/chemistry*; Water Pollutants, Chemical/chemistry*; Nanotubes, Carbon/chemistry*
  17. Meselhy MR, Abdel-Sattar OE, El-Mekkawy S, El-Desoky AM, Mohamed SO, Mohsen SM, et al.
    Molecules, 2020 Mar 05;25(5).
    PMID: 32151037 DOI: 10.3390/molecules25051179
    Phyllanthin and related lignans were found to be responsible, at least in part, for most of the activity of Phyllanthus species. This observation encouraged the authors to develop methods for the preparation of an extract rich in phyllanthin and related lignans from the aerial parts of P. niruri L. Direct extraction with solvents produced extracts with variable yields and contents of lignans. Lignans were identified by LC-ESI-MS analysis as phyllanthin (used as marker substance), hypophyllanthin, phylltetralin, nirtetralin, and niranthin. Extraction with boiling water produced 18.10 g% (w/w) extract with a trace amount of lignans (phyllanthin content of 0.33 ± 0.10 mg/g extract), while extraction with MeOH gave 3.6 g% w/w extract with a low phyllanthin content (3.1 mg/g extract), as determined by HPLC. However, Soxhlet extraction with hexane, CH2Cl2, or acetone gave extracts with low yields (0.82, 1.12, and 3.40 g% w/w, respectively) and a higher phyllanthin contents (36.2 ± 2.6, 11.7 ± 1.68, and 11.7 ± 1.10 mg/g extract, respectively). Extraction quality and efficiency were optimized by adopting the following three different approaches: (1) Alkaline digestion of the plant material with 30% potassium hydroxide yielded 3.1 g% w/w of purified extract with high phyllanthin content (22.34 ± 0.13 mg/g); (2) microwave-assisted extraction using 80% MeOH gave an extract with a better yield (8.13 g% w/w) and phyllanthin content (21.2 ± 1.30 mg/g) (after filtration through a Diaion HP-20 column); and (3) treatment of the ground plant material at 50 °C with two hydrolytic enzymes, cellulase (9 U/g for 12 h) and then, protease (4 U/g up to 72 h) optimized the yield of extract (13.92 g% w/w) and phyllanthin content (25.9 mg/g extract and total lignans content of 85.87 mg/g extract). In conclusion, the nonconventional methods presented here are superior for optimizing the yield of extract and its lignan contents from the aerial parts of P. niruri.
    Matched MeSH terms: Plant Extracts/chemistry*; Lignans/chemistry*; Phyllanthus/chemistry*; Plant Components, Aerial/chemistry*
  18. Md Ibrahim NNN, Hashim AM
    Sensors (Basel), 2020 Mar 12;20(6).
    PMID: 32178225 DOI: 10.3390/s20061572
    A biosensor formed by a combination of silicon (Si) micropore and graphene nanohole technology is expected to act as a promising device structure to interrogate single molecule biopolymers, such as deoxyribonucleic acid (DNA). This paper reports a novel technique of using a focused ion beam (FIB) as a tool for direct fabrication of both conical-shaped micropore in Si3N4/Si and a nanohole in graphene to act as a fluidic channel and sensing membrane, respectively. The thinning of thick Si substrate down to 50 µm has been performed prior to a multi-step milling of the conical-shaped micropore with final pore size of 3 µm. A transfer of graphene onto the fabricated conical-shaped micropore with little or no defect was successfully achieved using a newly developed all-dry transfer method. A circular shape graphene nanohole with diameter of about 30 nm was successfully obtained at beam exposure time of 0.1 s. This study opens a breakthrough in fabricating an integrated graphene nanohole and conical-shaped Si micropore structure for biosensor applications.
    Matched MeSH terms: DNA/chemistry; Graphite/chemistry*; Silicon/chemistry*; Silicon Compounds/chemistry
  19. Sulaiman N, Chee Beng Y, Ahmad Bustamam FK, Khairuddin NSK, Muhamad H
    Drug Test Anal, 2020 Apr;12(4):504-513.
    PMID: 31898859 DOI: 10.1002/dta.2760
    Cypermethrin is a pyrethroid insecticide commonly used to control bagworm infestation in oil palm plantations. It is applied through spraying onto the leaves where the bagworms reside. This article reports the fate of cypermethrin used in a Malaysian oil palm plantation during a typical dry season through the analysis of cypermethrin residue in environmental and palm oil samples collected from a supervised field trial. Residues of cypermethrin were not detected in the soil samples collected at different depths, water samples collected at different points in the experimental plots, and oil samples extracted from fresh fruit bunches (FFB) harvested from each plot for both single and double dosages of treatment throughout the study interval. Analysis of leaf samples, however, revealed that cypermethrin residue was detected for both pesticide treatments up to day 2 after cypermethrin application.
    Matched MeSH terms: Fruit/chemistry; Soil/chemistry; Plant Leaves/chemistry; Phoeniceae/chemistry
  20. Liu BL, Ooi CW, Ng IS, Show PL, Lin KJ, Chang YK
    Food Chem, 2020 Oct 15;327:127038.
    PMID: 32447136 DOI: 10.1016/j.foodchem.2020.127038
    Polyacrylonitrile nanofiber membrane functionalized with tris(hydroxymethyl)aminomethane (P-Tris) was used in affinity membrane chromatography for lysozyme adsorption. The effects of pH and protein concentration on lysozyme adsorption were investigated. Based on Langmuir model, the adsorption capacity of P-Tris nanofiber membrane was estimated to be 345.83 mg/g. For the operation of dynamic membrane chromatography with three-layer P-Tris nanofiber membranes, the optimal operating conditions were at pH 9, 1.0 mL/min of feed flow rate, and 2 mg/mL of feed concentration. Chicken egg white (CEW) was applied as the crude feedstock of lysozyme in the optimized dynamic membrane chromatography. The percent recovery and purification factor of lysozyme obtained from the chromatography were 93.28% and 103.98 folds, respectively. Our findings demonstrated the effectiveness of P-Tris affinity nanofiber membrane for the recovery of lysozyme from complex CEW solution.
    Matched MeSH terms: Egg White/chemistry*; Muramidase/chemistry; Tromethamine/chemistry*; Nanofibers/chemistry*
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