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  1. Fulltext Effects of Oxidation of Human Serum Albumin on the Binding of Aripiprazole
    Sakurama K, Nishi K, Chuang VTG, Hashimoto M, Yamasaki K, Otagiri M
    Biol Pharm Bull, 2020;43(6):1023-1026.
    PMID: 32475912 DOI: 10.1248/bpb.b20-00205
    Aripiprazole (ARP) is one of antipsychotics and binds to human serum albumin (HSA) with a high affinity. In this study, we investigated the binding characteristics of ARP to oxidized HSA as observed in chronic disease conditions. Oxidized HSAs were prepared using chloramine-T (CT-HSA) or metal-catalyzed oxidation system (MCO-HSA) in vitro, respectively. An increase in the carbonyl content was confirmed in oxidized HSAs. From the results of circular dichroism (CD) and tryptophan fluorescence spectra, no significant structural change of oxidized HSAs was observed. These results indicate that prepared HSAs are mildly oxidized and well reflects the status of HSA during chronic diseases. However, oxidized HSAs were observed to have a significant decrease in binding to ARP. The results of the induced CD spectrum suggested that ARP bound to oxidized HSAs with a similar orientation. These results suggest that oxidation of HSA during chronic disease state significantly affected the microenvironment of the binding site for ARP and binding capacity of HSA to ARP.
    Matched MeSH terms: Aripiprazole/chemistry*; Chloramines/chemistry; Tosyl Compounds/chemistry; Antipsychotic Agents/chemistry*
  2. Pahangensin A and B, two new antibacterial diterpenes from the rhizomes of Alpinia pahangensis Ridley
    Sivasothy Y, Ibrahim H, Paliany AS, Alias SA, Awang K
    Bioorg Med Chem Lett, 2013 Dec 1;23(23):6280-5.
    PMID: 24144849 DOI: 10.1016/j.bmcl.2013.09.082
    The rhizomes of Alpinia pahangensis Ridley yielded a new bis-labdanic diterpene for which the name pahangensin A (1) was proposed along with a new labdane diterpene, pahangensin B (2). Their structures were elucidated by spectroscopic methods including, 1D and 2D NMR techniques and LCMS-IT-TOF analysis. Pahangensin A (1) was found to be an antibacterial agent against Staphylococcus aureus, Bacillus cereus and Bacillus subtilis with MIC values less than 100 μg/mL, respectively. Pahangensin B (2) exhibited antibacterial activity (MIC <100 μg/mL) against B. cereus.
    Matched MeSH terms: Anti-Bacterial Agents/chemistry*; Diterpenes/chemistry*; Rhizome/chemistry*; Alpinia/chemistry*
  3. Can fluoride-oxalate and sodium citrate stabilise homocysteine levels after blood collection?
    Lopez JB, Peng CL
    Clin Chem Lab Med, 2003 Oct;41(10):1369-72.
    PMID: 14580168
    The concentration of homocysteine (Hcy) rises rapidly after the collection of blood. This feature requires blood to be collected into the anticoagulants EDTA or heparin and the plasma to then be immediately separated; alternatively, the blood may be kept on ice and centrifuged within 1 hour. The use of chemical preservatives has been proposed as a means of stabilising Hcy levels in whole blood after collection. The objective of this study was to determine whether the commonly available fluoride-oxalate (Fl-Ox) and sodium citrate (Na-Cit) containers could stabilise Hcy levels in blood. Our results showed that when blood was collected into potassium EDTA (K-EDTA) tubes, Hcy levels rose from initial levels, on standing at room temperature (approximately 25 degrees C), by an average of 21% after 3 hours and 32% after 5 hours. The initial Hcy levels of blood collected into Fl-Ox and Na-Cit containers, however, were lower, at averages of 89% and 91%, respectively, compared to that of the same samples when collected into K-EDTA tubes. Hcy in these samples subsequently rose on standing, and after 5 hours was, on the average, 10 and 13% higher, respectively, compared with the initial levels in K-EDTA tubes. We conclude that Fl-Ox and Na-Cit do not stabilise Hcy in blood after collection and should not be used as preservatives.
    Matched MeSH terms: Citrates/chemistry*; Fluorides/chemistry*; Homocysteine/chemistry; Oxalates/chemistry*
  4. 3D Flower-Like FeWO4/CeO2 Hierarchical Architectures on rGO for Durable and High-Performance Microalgae Biophotovoltaic Fuel Cells
    Karthikeyan C, Jenita Rani G, Ng FL, Periasamy V, Pappathi M, Jothi Rajan M, et al.
    Appl Biochem Biotechnol, 2020 Nov;192(3):751-769.
    PMID: 32557232 DOI: 10.1007/s12010-020-03352-4
    A facile chemical reduction approach is adopted for the synthesis of iron tungstate (FeWO4)/ceria (CeO2)-decorated reduced graphene oxide (rGO) nanocomposite. Surface morphological studies of rGO/FeWO4/CeO2 composite reveal the formation of hierarchical FeWO4 flower-like microstructures on rGO sheets, in which the CeO2 nanoparticles are decorated over the FeWO4 microstructures. The distinct anodic peaks observed for the cyclic voltammograms of studied electrodes under light/dark regimes validate the electroactive proteins present in the microalgae. With the cumulative endeavors of three-dimensional FeWO4 microstructures, phase effect between rGO sheet and FeWO4/CeO2, highly exposed surface area, and light harvesting property of CeO2 nanoparticles, the relevant rGO/FeWO4/CeO2 nanocomposite demonstrates high power and stable biophotovoltaic energy generation compared with those of previous reports. Thus, these findings construct a distinct horizon to tailor a ternary nanocomposite with high electrochemical activity for the construction of cost-efficient and environmentally benign fuel cells.
    Matched MeSH terms: Cerium/chemistry*; Electrochemistry; Graphite/chemistry*; Nanoparticles/chemistry; Nanocomposites/chemistry
  5. Morphology and magnetic characterisation of aluminium substituted yttrium-iron garnet nanoparticles prepared using sol gel technique
    Yahya N, Al Habashi RM, Koziol K, Borkowski RD, Akhtar MN, Kashif M, et al.
    J Nanosci Nanotechnol, 2011 Mar;11(3):2652-6.
    PMID: 21449447
    Aluminum substituted yttrium iron garnet nano particles with compositional variation of Y(3.0-x) A1(x)Fe5O12, where x = 0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 were prepared using sol gel technique. The X-ray diffraction results showed that the best garnet phase appeared when the sintering temperature was 800 degrees C. Nano-crystalline particles with high purity and sizes ranging from 20 to 100 nm were obtained. It was found that the aluminum substitution had resulted in a sharp fall of the d-spacing when x = 2, which we speculated is due to the preference of the aluminum atoms to the smaller tetrahedron and octahedron sites instead of the much larger dodecahedron site. High resolution transmission electron microscope (HRTEM) and electron diffraction (ED) patterns showed single crystal nanoparticles were obtained from this method. The magnetic measurement gave moderate values of initial permeability; the highest value of 5.3 was shown by sample Y3Fe5O12 at more than 100 MHz which was attributed to the morphology of the microstructure which appeared to be homogeneous. This had resulted in an easy movement of domain walls. The substitution of aluminum for yttrium is speculated to cause a cubic to rhombodedral structural change and had weakened the super-exchange interactions thus a fall of real permeability was observed. This might have created a strain in the sub-lattices and had subsequently caused a shift of resonance frequencies to more than 1.8 GHz when x > 0.5.
    Matched MeSH terms: Aluminum/chemistry*; Iron/chemistry*; Yttrium/chemistry*; Nanostructures/chemistry*
  6. Exploring role of polysaccharides present in Ganoderma lucidium extract powder and probiotics as solid carriers in development of liquisolid formulation loaded with quercetin: A novel study
    Khursheed R, Singh SK, Gulati M, Wadhwa S, Kapoor B, Pandey NK, et al.
    Int J Biol Macromol, 2021 Jul 31;183:1630-1639.
    PMID: 34015408 DOI: 10.1016/j.ijbiomac.2021.05.064
    Ganoderma lucidium extract powder (GLEP) contains various polysaccharides which are well known for their antioxidant and anti-inflammatory actions. Probiotics (PB) are well-established for providing a plethora of health benefits. Hence, use of mushroom polysaccharides and probiotics as carriers to solidify liquisolid formulation is anticipated to function as functional excipients i.e. as adsorbent that may provide therapeutic benefits. Quercetin (QUR) has been used as model lipophilic drug in this study. QUR loaded liquisolid compacts (LSCs) were formulated using Tween 80 as solvent. These were further solidified using a combination of PB and GLEP as carriers. Aerosil-200 (A-200) was used as coating agent. The formulation exhibited very good flow characteristics. Dissolution rate of raw QUR was found to be less than 10% in 60 min while in case of QUR loaded LSCs, more than 90% drug release was observed within 5 min. Absence of crystalline peaks of QUR in the DSC and PXRD reports of LSCs and their porous appearance in SEM micrographs indicate that QUR was successfully incorporated in the LSCs. The developed formulation was found to be stable on storage under accelerated stability conditions.
    Matched MeSH terms: Quercetin/chemistry*; Probiotics/chemistry*; Ganoderma/chemistry*; Fungal Polysaccharides/chemistry*
  7. Bioelectrofuel Synthesis by Nanoenzymes: Novel Alternatives to Conventional Enzymes
    Singh L, Rana S, Thakur S, Pant D
    Trends Biotechnol, 2020 05;38(5):469-473.
    PMID: 31932067 DOI: 10.1016/j.tibtech.2019.12.017
    Recent bioinspired efforts of designing novel nanoenzyme-based electrocatalysts are driven by the urgency of making bioelectrofuels more affordable and efficient. Unlike natural enzymes, nanoenzyme-modified electrodes with large surface areas enclose numerous biomimicking active sites to facilitate enhanced microbial growth followed by increased reactant-to-bioelectrofuel conversion.
    Matched MeSH terms: Enzymes/chemistry*; Hydrogenase/chemistry; Peroxidase/chemistry; Nanostructures/chemistry*
  8. Composite of medium-chain-length polyhydroxyalkanoates-co-methyl acrylate and carbon nanotubes as innovative electrodes modifier in microbial fuel cell
    Sirajudeen AAO, Annuar MSM, Subramaniam R
    Biotechnol Appl Biochem, 2021 Apr;68(2):307-318.
    PMID: 32314420 DOI: 10.1002/bab.1928
    A microbial fuel cell is a sustainable and environmental-friendly device that combines electricity generation and wastewater treatment through metabolic activities of microorganisms. However, low power output from inadequate electron transfer to the anode electrode hampers its practical implementation. Nanocomposites of oxidized carbon nanotubes and medium-chain-length polyhydroxyalkanoates (mcl-PHA) grafted with methyl acrylate monomers enhance the electrochemical function of electrodes in microbial fuel cell. Extensive polymerization of methyl acrylate monomers within mcl-PHA matrix, and homogenous dispersion of carbon nanotubes within the graft matrix are responsible for the enhancement. Modified electrodes exhibit high conductivities, better redox peak and reduction of cell internal resistance up to 76%. A stable voltage output at almost 700 mV running for 225 H generates maximum power and current density of 351 mW/m2 and 765 mA/m2 , respectively. Superior biofilm growth on modified surface is responsible for improved electron transfer to the anode hence stable and elevated power output generation.
    Matched MeSH terms: Acrylates/chemistry*; Nanotubes, Carbon/chemistry*; Nanocomposites/chemistry*; Polyhydroxyalkanoates/chemistry*
  9. Interfacial elastic relaxation during the ejection of bi-layered tablets
    Anuar MS, Briscoe BJ
    Int J Pharm, 2010 Mar 15;387(1-2):42-7.
    PMID: 19963050 DOI: 10.1016/j.ijpharm.2009.11.031
    The predilection of a bi-layered tablet to fail in the interface region after its initial formation in the compaction process reduces its practicality as a choice for controlled release solid drug delivery system. Hence, a fundamental appreciation of the governing mechanism that causes the weakening of the interfacial bonds within the bi-layered tablet is crucial in order to improve the overall bi-layered tablet mechanical integrity. This work has shown that the occurrence of the elastic relaxation in the interface region during the ejection stage of the compaction process decreases with the increase in the bi-layered tablet interface strength. This is believed to be due to the increase in the plastic bonding in the interface region. The tablet diametrical elastic relaxation affects the tablet height elastic relaxation, where the impediment of the tablet height expansion is observed when the interface region experiences a diametrical expansion.
    Matched MeSH terms: Cellulose/chemistry*; Chemistry, Pharmaceutical/methods; Excipients/chemistry*
  10. Recent advances in TPGS-based nanoparticles of docetaxel for improved chemotherapy
    Choudhury H, Gorain B, Pandey M, Kumbhar SA, Tekade RK, Iyer AK, et al.
    Int J Pharm, 2017 Aug 30;529(1-2):506-522.
    PMID: 28711640 DOI: 10.1016/j.ijpharm.2017.07.018
    Docetaxel (DTX) is one of the important antitumor drugs, being used in several common chemotherapies to control leading cancer types. Severe toxicities of the DTX are prominent due to sudden parenteral exposure of desired loading dose to maintain the therapeutic concentration. Field of nanotechnology is leading to resist sudden systemic exposure of DTX with more specific delivery to the site of cancer. Further nanometric size range of the formulation aid for prolonged circulation, thereby extensive exposure results better efficacy. In this article, we extensively reviewed the therapeutic benefit of incorporating d-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS, or simply TPGS) in the nanoparticle (NP) formulation of DTX for improved delivery, tumor control and tolerability. TPGS is well accepted nonionic-ampiphilic polymer which has been identified in the role of emulsifier, stabilizer, penetration enhancer, solubilizer and in protection in micelle. Simultaneously, P-glycoprotein inhibitory activity of TPGS in the multidrug resistant (MDR) cancer cells along with its apoptotic potential are the added advantage of TPGS to be incorporated in nano-chemotherapeutics. Thus, it could be concluded that TPGS based nanoparticulate application is an advanced approach to improve therapeutic efficacy of chemotherapeutic agents by better internalization and sustained retention of the NPs.
    Matched MeSH terms: Drug Carriers/chemistry*; Polyethylene Glycols/chemistry; Vitamin E/chemistry*; Nanoparticles/chemistry*
  11. Changes in Phenolic Compounds Profiles in Tea Extracts and the Composition of these Phenolic Compounds in Yogurt
    Shori AB, Muniandy P, Baba AS
    Recent Pat Food Nutr Agric, 2021;12(1):36-44.
    PMID: 33231153 DOI: 10.2174/2212798411999201123205022
    BACKGROUND: Green, white, and black tea water extracts are rich in phenolic compounds.

    OBJECTIVE: The changes in phenolic compound profiles of green, white, and black tea (GT, WT, & BT respectively) water extracts and their respective yogurt were investigated.

    METHODS: Three types of yogurt with tea water extracts were prepared, and the phenolic compound profiles were analyzed using the liquid chromatography-mass spectrometry (LC-MS) method.

    RESULTS: The present data found that flavonol glycosides such as kaempferol-3-rutinoside and quercetin-rhamnosylgalactoside or rutinoside were present in WT extract, whereas catechin derivatives such as gallocatechin (GC) and epigallocatechin (EGC) were present in GT extract. Moreover, theaflavin-3-O-gallate was observed in BT extract. Many of the catechin and its derivatives detected in the tea extracts were not identified in the tea yogurt samples. However, new phenolic compounds were present in GT-yogurt (i.e., kaempferol-3-rutinoside and quinic acid conjugate) but absent in GT extract.

    CONCLUSION: GT, WT, & BT extracts could be used to enriched-yogurt with phenolic compounds, which may have antioxidant properties.

    Matched MeSH terms: Food Additives/chemistry*; Phenols/chemistry*; Plant Extracts/chemistry*; Camellia sinensis/chemistry*
  12. Aptamer-17β-estradiol-antibody sandwich ELISA for determination of gynecological endocrine function
    Huang Y, Zhang L, Li Z, Gopinath SCB, Chen Y, Xiao Y
    Biotechnol Appl Biochem, 2021 Aug;68(4):881-888.
    PMID: 33245588 DOI: 10.1002/bab.2008
    17β-Estradiol-E2 (17β-E2) is a steroid hormone that plays a major role in the reproductive endocrine system and is involved in various processes, such as pregnancy, fertility, and menopause. In this study, the performance of an enzyme-linked immunosorbent assay (ELISA) for 17β-E2 quantification was enhanced by using a gold nanoparticle (GNP)-conjugated aptamer. An anti-17β-E2-aptamer-GNP antibody was immobilized on an amine-modified ELISA surface. Then, 17β-E2 was allowed to interact with and be sandwiched by antibodies. Aptamer-GNP conjugation was confirmed by colorimetric assays via the naked eye and UV-visible light spectroscopy. The detection limit based on a signal-to-noise ratio (S/N) of 3 was estimated to be 1.5 nM (400 pg/mL), and the linear range was 1.5-50 nM. Control experiments (without 17β-E2/with a complementary aptamer sequence/with a nonimmune antibody) confirmed the specific detection of 17β-E2. Moreover, 17β-E2 spiking of human serum did not interrupt the interaction between 17β-E2 and its antibody and aptamer. Thus, the developed ELISA can be used as an alternate assay for quantification of 17β-E2 and assessment of endocrine-related gynecological problems.
    Matched MeSH terms: Antibodies/chemistry*; Gold/chemistry*; Aptamers, Nucleotide/chemistry*; Metal Nanoparticles/chemistry*
  13. Antifouling polyethersulfone hemodialysis membranes incorporated with poly (citric acid) polymerized multi-walled carbon nanotubes
    Abidin MNZ, Goh PS, Ismail AF, Othman MHD, Hasbullah H, Said N, et al.
    Mater Sci Eng C Mater Biol Appl, 2016 Nov 01;68:540-550.
    PMID: 27524052 DOI: 10.1016/j.msec.2016.06.039
    Poly (citric acid)-grafted-MWCNT (PCA-g-MWCNT) was incorporated as nanofiller in polyethersulfone (PES) to produce hemodialysis mixed matrix membrane (MMM). Citric acid monohydrate was polymerized onto the surface of MWCNTs by polycondensation. Neat PES membrane and PES/MWCNTs MMMs were fabricated by dry-wet spinning technique. The membranes were characterized in terms of morphology, pure water flux (PWF) and bovine serum albumin (BSA) protein rejection. The grafting yield of PCA onto MWCNTs was calculated as 149.2%. The decrease of contact angle from 77.56° to 56.06° for PES/PCA-g-MWCNTs membrane indicated the increase in surface hydrophilicity, which rendered positive impacts on the PWF and BSA rejection of the membrane. The PWF increased from 15.8Lm(-2)h(-1) to 95.36Lm(-2)h(-1) upon the incorporation of PCA-g-MWCNTs due to the attachment of abundant hydrophilic groups that present on the MWCNTs, which have improved the affinity of membrane towards the water molecules. For protein rejection, the PES/PCA-g-MWCNTs MMM rejected 95.2% of BSA whereas neat PES membrane demonstrated protein rejection of 90.2%. Compared to commercial PES hemodialysis membrane, the PES/PCA-g-MWCNTs MMMs showed less flux decline behavior and better PWF recovery ratio, suggesting that the membrane antifouling performance was improved. The incorporation of PCA-g-MWCNTs enhanced the separation features and antifouling capabilities of the PES membrane for hemodialysis application.
    Matched MeSH terms: Polymers/chemistry*; Serum Albumin, Bovine/chemistry; Sulfones/chemistry*; Nanotubes, Carbon/chemistry*
  14. Removal of emerging perfluorooctanoic acid and perfluorooctane sulfonate contaminants from lake water
    Pramanik BK, Pramanik SK, Sarker DC, Suja F
    Environ Technol, 2017 Aug;38(15):1937-1942.
    PMID: 27666670 DOI: 10.1080/09593330.2016.1240716
    Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are the major polyfluoroalkyl substances (PFASs) contaminating global water environment. This study investigated the efficiency of granular activated carbon (GAC), ultrafiltration (UF) and nanofiltration (NF) treatment for removing PFOS and PFOA contaminants from lake water. NF gave greater removal of all contaminant types (in terms of organic matter, PFOS and PFOA) than GAC treatment which in turn was greater than UF treatment. The lower removal by UF was due to larger pore size of the membrane compared to the size of the target contaminants. For all treatment processes, lower pH (4) in the feedwater showed greater rejection of the organics and selected PFASs. This was likely due to increase in the electrostatic repulsion between solute and sorbent. It could be observed that on increasing the concentration of organics in the feed solution, the rejection of PFOA/PFOS decreased which was due to competition between organics and PFOS/PFOA for binding sites on the membrane/activated carbon surface. It was also noted that protein content led to greater influence for lower rejection of the PFOA/PFOS than carbohydrate or DOC content. This study demonstrated the potential use of membrane processes for removing emerging persistent organic pollutant removal from lake water.
    Matched MeSH terms: Caprylates/chemistry*; Fluorocarbons/chemistry*; Water Pollutants, Chemical/chemistry*; Alkanesulfonic Acids/chemistry*
  15. Fulltext Subcritical Water Technology for Enhanced Extraction of Biochemical Compounds from Chlorella vulgaris
    Awaluddin SA, Thiruvenkadam S, Izhar S, Hiroyuki Y, Danquah MK, Harun R
    Biomed Res Int, 2016;2016:5816974.
    PMID: 27366748 DOI: 10.1155/2016/5816974
    Subcritical water extraction (SWE) technology has been used for the extraction of active compounds from different biomass materials with low process cost, mild operating conditions, short process times, and environmental sustainability. With the limited application of the technology to microalgal biomass, this work investigates parametrically the potential of subcritical water for high-yield extraction of biochemicals such as carbohydrates and proteins from microalgal biomass. The SWE process was optimized using central composite design (CCD) under varying process conditions of temperature (180-374°C), extraction time (1-20 min), biomass particulate size (38-250 μm), and microalgal biomass loading (5-40 wt.%). Chlorella vulgaris used in this study shows high volatile matter (83.5 wt.%) and carbon content (47.11 wt.%), giving advantage as a feedstock for biofuel production. The results showed maximum total carbohydrate content and protein yields of 14.2 g/100 g and 31.2 g/100 g, respectively, achieved under the process conditions of 277°C, 5% of microalgal biomass loading, and 5 min extraction time. Statistical analysis revealed that, of all the parameters investigated, temperature is the most critical during SWE of microalgal biomass for protein and carbohydrate production.
    Matched MeSH terms: Carbohydrates/chemistry; Proteins/chemistry; Water/chemistry*; Chlorella vulgaris/chemistry*
  16. Functionalization of magnetic chitosan with graphene oxide for removal of cationic and anionic dyes from aqueous solution
    Gul K, Sohni S, Waqar M, Ahmad F, Norulaini NAN, A K MO
    Carbohydr Polym, 2016 Nov 05;152:520-531.
    PMID: 27516300 DOI: 10.1016/j.carbpol.2016.06.045
    In the present study, we decorated chitosan (©) with Fe3O4 nanoparticles followed by cross-linking with GO to prepare Fe3O4 supported chitosan-graphene oxide composite (Fe3O4©-GO). Different properties of synthesized material were investigated by SEM, XRD, FTIR, TGA and EDX. Batch adsorption experiments were performed to remove toxic cationic and anionic dyes from industrial wastewater. To maximize removal efficiency of composite material, effect of pH (4-12), time (0-80min), Fe3O4©-GO dosage (2-10mg), initial dye concentration (2-30μgmL̄ (1)) and temperature (303, 313, and 323K) were studied. The uptake of dyes presented relatively fast adsorption kinetics with pseudo-second-order equation as the best fitting model. To understand the interaction of dye with adsorbent, Langmuir and Freundlich isotherm were applied. Thermodynamic studies were conducted to calculate the changes in free energy (ΔG(0)), enthalpy (ΔH(0)) and entropy (ΔS(0)). In view of practical application, the influence of ionic strength, recycling as well as investigations based on percent recoveries from spiked real water samples were also taken into account.
    Matched MeSH terms: Coloring Agents/chemistry*; Graphite/chemistry*; Chitosan/chemistry*; Ferrosoferric Oxide/chemistry*
  17. A structurally diverse library of safe-by-design citrem-phospholipid lamellar and non-lamellar liquid crystalline nano-assemblies
    Azmi ID, Wibroe PP, Wu LP, Kazem AI, Amenitsch H, Moghimi SM, et al.
    J Control Release, 2016 Oct 10;239:1-9.
    PMID: 27524284 DOI: 10.1016/j.jconrel.2016.08.011
    Non-lamellar liquid crystalline aqueous nanodispersions, known also as ISAsomes (internally self-assembled 'somes' or nanoparticles), are gaining increasing interest in drug solubilisation and bio-imaging, but they often exhibit poor hemocompatibility and induce cytotoxicity. This limits their applications in intravenous drug delivery and targeting. Using a binary mixture of citrem and soy phosphatidylcholine (SPC) at different weight ratios, we describe a library of colloidally stable aqueous and hemocompatible nanodispersions of diverse nanoarchitectures (internal self-assembled nanostructures). This engineered library is structurally stable in human plasma as well as being hemocompatible (non-hemolytic, and poor activator of the complement system). By varying citrem to lipid weight ratio, the nanodispersion susceptibility to macrophage uptake could also be modulated. Finally, the formation of nanodispersions comprising internally V2 (inverse bicontinuous cubic) and H2 (inverse hexagonal) nanoarchitectures was achieved without the use of an organic solvent, a secondary emulsifier, or high-energy input. The tunable binary citrem/SPC nanoplatform holds promise for future development of hemocompatible and immune-safe nanopharmaceuticals.
    Matched MeSH terms: Drug Carriers/chemistry*; Phospholipids/chemistry*; Nanostructures/chemistry*; Liquid Crystals/chemistry*
  18. A new approach of probe sonication assisted ionic liquid conversion of glucose, cellulose and biomass into 5-hydroxymethylfurfural
    Sarwono A, Man Z, Muhammad N, Khan AS, Hamzah WSW, Rahim AHA, et al.
    Ultrason Sonochem, 2017 Jul;37:310-319.
    PMID: 28427638 DOI: 10.1016/j.ultsonch.2017.01.028
    5-Hydroxymethylfurfural (HMF) has been identified as a promising biomass-derived platform chemical. In this study, one pot production of HMF was studied in ionic liquid (IL) under probe sonication technique. Compared with the conventional heating technique, the use of probe ultrasonic irradiation reduced the reaction time from hours to minutes. Glucose, cellulose and local bamboo, treated with ultrasonic, produced HMF in the yields of 43%, 31% and 13% respectively, within less than 10min. The influence of various parameters such as acoustic power, reaction time, catalysts and glucose loading were studied. About 40% HMF yield at glucose conversion above 90% could be obtained with 2% of catalyst in 3min. Negligible amount of soluble by-product was detected, and humin formation could be controlled by adjusting the different process parameters. Upon extraction of HMF, the mixture of ionic liquid and catalyst could be reused and exhibited no significant reduction of HMF yield over five successive runs. The purity of regenerated [C4C1im]Cl and HMF was confirmed by NMR spectroscopy, indicating neither changes in the chemical structure nor presence of any major contaminants during the conversion under ultrasonic treatment. 13C NMR suggests that [C4C1im]Cl/CrCl3 catalyses mutarotation of α-glucopyranose to β-glucopyranose leading to isomerization and finally conversion to HMF. The experimental results demonstrate that the use of probe sonication technique for conversion to HMF provides a positive process benefit.
    Matched MeSH terms: Cellulose/chemistry*; Furaldehyde/chemistry; Glucose/chemistry*; Ionic Liquids/chemistry*
  19. Preparation and characterization of nanocrystalline cellulose from Acacia mangium and its reinforcement potential
    Jasmani L, Adnan S
    Carbohydr Polym, 2017 Apr 01;161:166-171.
    PMID: 28189225 DOI: 10.1016/j.carbpol.2016.12.061
    Acacia mangium, a fast growing tree is widely planted in Malaysia. Converting Acacia wood into nanocellulose could create new value added products for forest-based industry. Nanocrystalline cellulose (NCC) was prepared from Acacia mangium wood pulp via 64wt% sulfuric acid hydrolysis. Prior to acid hydrolysis, Acacia mangium was subjected to pulping followed by bleaching in order to remove non-cellulosic fragments. Acid hydrolysis was carried out on bleached pulp to produce the needle-like NCC with 79% crystallinity and aspect ratio of 26. The resulting NCC was mixed with PVA as a reinforcement material. Incorporation of 2% NCC improved the tensile of the NCC-PVA film by 30%.
    Matched MeSH terms: Acacia/chemistry*; Cellulose/chemistry; Wood/chemistry; Nanoparticles/chemistry*
  20. Sonochemical degradation of endocrine-disrupting organochlorine pesticide Dicofol: Investigations on the transformation pathways of dechlorination and the influencing operating parameters
    Debabrata P, Sivakumar M
    Chemosphere, 2018 Aug;204:101-108.
    PMID: 29655102 DOI: 10.1016/j.chemosphere.2018.04.014
    Dicofol, an extensively used organochlorine pesticide and a recommended Stockholm convention persistent organic pollutant (POP) candidate is well known for its endocrine disruptive properties. The sonochemical degradation of Dicofol in aqueous media has been investigated using a 20-kHz probe type sonicator with power inputs from 150 to 450 W. The degradation rate was determined as a function of concentration of Dicofol, solution pH, bulk phase temperature, ultrasonic power density and H2O2 addition. At optimum operating conditions, the pseudo-first-order degradation rate constant (k) was determined to be 0.032 min-1 and the extent of degradation was found to be 86% within 60 min of ultrasound treatment. High performance liquid chromatography (HPLC) and Gas chromatography coupled with mass spectroscopy (GC-MS) analysis indicated the presence of degraded products. The obtained results of Dicofol degradation and control experiments in the presence of H2O2 and radical scavenger test suggest thermal decomposition along with radical attack at bubble-vapor interface to be the dominant degradation pathway. Sonochemical treatment is effective and promising for successful removal of harmful pesticides such as Dicofol and superior removal efficiency for other POPs is expected in the near future with the successful implementation of ultrasound-based wastewater treatment.
    Matched MeSH terms: Dicofol/chemistry*; Hydrogen Peroxide/chemistry; Pesticides/chemistry; Endocrine Disruptors/chemistry
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