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  1. Influence of omega fatty acids on skin permeation of a coenzyme Q10 nanoemulsion cream formulation: characterization, in silico and ex vivo determination
    Tou KAS, Rehman K, Ishak WMW, Zulfakar MH
    Drug Dev Ind Pharm, 2019 Sep;45(9):1451-1458.
    PMID: 31216907 DOI: 10.1080/03639045.2019.1628042
    Objective: The aim of this study was to develop a coenzyme Q10 nanoemulsion cream, characterize and to determine the influence of omega fatty acids on the delivery of coenzyme Q10 across model skin membrane via ex vivo and in silico techniques. Methods: Coenzyme Q10 nanoemulsion creams were prepared using natural edible oils such as linseed, evening primrose, and olive oil. Their mechanical features and ability to deliver CoQ10 across rat skin were characterized. Computational docking analysis was performed for in silico evaluation of CoQ10 and omega fatty acid interactions. Results: Linseed, evening primrose, and olive oils each produced nano-sized emulsion creams (343.93-409.86 nm) and exhibited excellent rheological features. The computerized docking studies showed favorable interactions between CoQ10 and omega fatty acids that could improve skin permeation. The three edible-oil nanoemulsion creams displayed higher ex vivo skin permeation and drug flux compared to the liquid-paraffin control cream. The linseed oil formulation displayed the highest skin permeation (3.97 ± 0.91 mg/cm2) and drug flux (0.19 ± 0.05 mg/cm2/h). Conclusion: CoQ10 loaded-linseed oil nanoemulsion cream displayed the highest skin permeation. The highest permeation showed by linseed oil nanoemulsion cream may be due to the presence of omega-3, -6, and -9 fatty acids which might serve as permeation enhancers. This indicated that the edible oil nanoemulsion creams have potential as drug vehicles that enhance CoQ10 delivery across skin.
    Matched MeSH terms: Nanoparticles/chemistry
  2. Fulltext Regioselective Sequential Modification of Chitosan via Azide-Alkyne Click Reaction: Synthesis, Characterization, and Antimicrobial Activity of Chitosan Derivatives and Nanoparticles
    Sarwar A, Katas H, Samsudin SN, Zin NM
    PLoS One, 2015;10(4):e0123084.
    PMID: 25928293 DOI: 10.1371/journal.pone.0123084
    Recently, the attention of researchers has been drawn toward the synthesis of chitosan derivatives and their nanoparticles with enhanced antimicrobial activities. In this study, chitosan derivatives with different azides and alkyne groups were synthesized using click chemistry, and these were further transformed into nanoparticles by using the ionotropic gelation method. A series of chitosan derivatives was successfully synthesized by regioselective modification of chitosan via an azide-alkyne click reaction. The amino moieties of chitosan were protected during derivatization by pthaloylation and subsequently unblocked at the end to restore their functionality. Nanoparticles of synthesized derivatives were fabricated by ionic gelation to form complexes of polyanionic penta-sodium tripolyphosphate (TPP) and cationic chitosan derivatives. Particle size analysis showed that nanoparticle size ranged from 181.03 ± 12.73 nm to 236.50 ± 14.32 nm and had narrow polydispersity index and positive surface charge. The derivatives and corresponding nanoparticles were evaluated in vitro for antibacterial and antifungal activities against three gram-positive and gram-negative bacteria and three fungal strains, respectively. The minimum inhibitory concentration (MIC) of all derivatives ranged from 31.3 to 250 µg/mL for bacteria and 188 to1500 µg/mL for fungi and was lower than that of native chitosan. The nanoparticles with MIC ranging from 1.56 to 25 µg/mLfor bacteria and 94 to 750 µg/mL for fungi exhibited higher activity than the chitosan derivatives. Chitosan O-(1-methylbenzene) triazolyl carbamate and chitosan O-(1-methyl phenyl sulfide) triazolyl carbamate were the most active against the tested bacterial and fungal strains. The hemolytic assay on erythrocytes and cell viability test on two different cell lines (Chinese hamster lung fibroblast cells V79 and Human hepatic cell line WRL68) demonstrated the safety; suggesting that these derivatives could be used in future medical applications. Chitosan derivatives with triazole functionality, synthesized by Huisgen 1,3-dipolar cycloaddition, and their nanoparticles showed significant enhancement in antibacterial and antifungal activities in comparison to those associated with native, non-altered chitosan.
    Matched MeSH terms: Nanoparticles/chemistry
  3. Fulltext Green biosynthesis of silver nanoparticles using Callicarpa maingayi stem bark extraction
    Shameli K, Bin Ahmad M, Jaffar Al-Mulla EA, Ibrahim NA, Shabanzadeh P, Rustaiyan A, et al.
    Molecules, 2012 Jul 16;17(7):8506-17.
    PMID: 22801364 DOI: 10.3390/molecules17078506
    Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of silver nanoparticles using Callicarpa maingayi stem bark extract has been reported. Characterizations of nanoparticles were done using different methods, which include; ultraviolet-visible spectroscopy (UV-Vis), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) spectrometry, zeta potential measurements and Fourier transform infrared (FT-IR) spectroscopy. UV-visible spectrum of the aqueous medium containing silver nanoparticles showed absorption peak at around 456 nm. The TEM study showed that mean diameter and standard deviation for the formation of silver nanoparticles were 12.40 ± 3.27 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc) structure. The most needed outcome of this work will be the development of value added products from Callicarpa maingayi for biomedical and nanotechnology based industries.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  4. Electroimmunodetection of cardiac C-reactive protein for determining myocardial Injury
    Gan X, Gong T, Zheng Y, Gopinath SCB, Zhao K
    Biotechnol Appl Biochem, 2021 Apr;68(2):272-278.
    PMID: 32275089 DOI: 10.1002/bab.1921
    C-reactive protein (CRP) is an acute phase reactant to be a marker of inflammation and has been correlated with the cardiac injury. An immunoassay was performed using anti-human CRP antibody on an InterDigitated electrode (IDE) sensor to determine and specify CRP concentration for diagnosing the condition of myocardial inflammation. To promote the detection, gold nanoparticle (GNP) was seeded on the aminated-IDE surface. Anti-CRP was hitched on the GNP-seeded surface and identified the abundance of CRP. The limit of quantification was found as 100 fM, and the higher current response was noticed by increasing CRP concentrations with the sensitivity at 1 pM. Furthermore, CRP-spiked human serum did not interfere the determination of CRP and increased the current response, indicating suitability for a real-life sample. Similarly, the control experiments with nonimmune antibody Troponin I are not showing the definite current responses, proving the selective identification of CRP. This method of diagnosing is needful to determine the cardiovascular injury at the right time.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  5. Ameliorative effect of Albizia chinensis synthesized ZnO-NPs on Mycoplasma pneumoniae infected pneumonia mice model
    Yu L, Lu M, Zhang W, Alarfaj AA, Hirad AH, Zhang H
    Microb Pathog, 2020 Apr;141:103960.
    PMID: 31953224 DOI: 10.1016/j.micpath.2019.103960
    BACKGROUND: Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia (CAP) among the children and adults that results upper and lower respiratory tract infections.

    OBJECTIVE: This study was aimed to inspect the ameliorative action of A. chinensis synthesized ZnONPs against M. pneumoniae infected pneumonia mice model.

    MATERIALS AND METHODS: ZnO NPs was synthesized from Albizia chinensis bark extract and characterized by UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), Transmission Electron Microscopy (TEM), energy dispersive X-ray (EDX) and atomic force microscope (AFM) analyses. The antibacterial effectual of synthesized ZnONPs were examined against clinical pathogens. The pneumonia was induced to BALB/c mice via injecting the M. pneumoniae and treated with synthesized ZnONPs, followed by the total protein content, total cell counts and inflammatory mediators level was assessed in the BALF of experimental animals. The Histopathological investigation was done in the lung tissues of test animals.

    RESULTS: The outcomes of this work revealed that the formulated ZnONPs was quasi-spherical, radial and cylindrical; the size was identified as 116.5 ± 27.45 nm in diameter. The in vitro antimicrobial potential of formulated ZnO-NPs displayed noticeable inhibitory capacity against the tested fungal and bacterial strains. The administration of synthesized ZnO-NPs in MP infected mice model has significantly reduced the levels of total protein, inflammatory cells, inflammatory cytokines such as IL-1, IL-6, IL-8, tumour necrosis factor-alpha (TNF-a) and transforming growth factor (TGF). Besides, the histopathological examination of MP infected mice lung tissue showed the cellular arrangements were effectively retained after administration of synthesized ZnO-NPs.

    CONCLUSION: In conclusion, synthesized ZnO-NPs alleviate pneumonia progression via reducing the level of inflammatory cytokines and inflammatory cells in MP infected mice model.

    Matched MeSH terms: Metal Nanoparticles/chemistry*
  6. Dendrimer-like nanoparticles based β-galactosidase assembly for enhancing its selectivity toward transgalactosylation
    Misson M, Du X, Jin B, Zhang H
    Enzyme Microb Technol, 2016 Mar;84:68-77.
    PMID: 26827776 DOI: 10.1016/j.enzmictec.2015.12.008
    Functional nanomaterials have been pursued to assemble nanobiocatalysts since they can provide unique hierarchical nanostructures and localized nanoenvironments for enhancing enzyme specificity, stability and selectivity. Functionalized dendrimer-like hierarchically porous silica nanoparticles (HPSNs) was fabricated for assembling β-galactosidase nanobiocatalysts for bioconversion of lactose to galacto-oligosaccharides (GOS). The nanocarrier was functionalized with amino (NH2) and carboxyl (COOH) groups to facilitate enzyme binding, benchmarking with non-functionalized HPSNs. Successful conjugation of the functional groups was confirmed by FTIR, TGA and zeta potential analysis. HPSNs-NH2 showed 1.8-fold and 1.1-fold higher β-galactosidase adsorption than HPSNs-COOH and HPSNs carriers, respectively, with the highest enzyme adsorption capacity of 328mg/g nanocarrier at an initial enzyme concentration of 8mg/ml. The HPSNs-NH2 and β-galactosidase assembly (HPSNs-NH2-Gal) demonstrated to maintain the highest activity at all tested enzyme concentrations and exhibited activity up to 10 continuous cycles. Importantly, HPSNs-NH2-Gal was simply recycled through centrifugation, overcoming the challenging problems of separating the nanocarrier from the reaction medium. HPSNs-NH2-Gal had distinguished catalytic reaction profiles by favoring transgalactosylation, enhancing GOS production of up to 122g/l in comparison with 56g/l by free β-galactosidase. Furthermore, it generated up to 46g/l GOS at a lower initial lactose concentration while the free counterpart had negligible GOS production as hydrolysis was overwhelmingly dominant in the reaction system. Our research findings show the amino-functionalized HPSNs can selectively promote the enzyme activity of β-galactosidase for transgalactosylation, which is beneficial for GOS production.
    Matched MeSH terms: Nanoparticles/chemistry
  7. Ginger and its active compounds in cancer therapy: From folk uses to nano-therapeutic applications
    Mahomoodally MF, Aumeeruddy MZ, Rengasamy KRR, Roshan S, Hammad S, Pandohee J, et al.
    Semin Cancer Biol, 2021 Feb;69:140-149.
    PMID: 31412298 DOI: 10.1016/j.semcancer.2019.08.009
    Ginger is a spice that is renowned for its characteristic aromatic fragrance and pungent taste, with documented healing properties. Field studies conducted in several Asian and African countries revealed that ginger is used traditionally in the management of cancer. The scientific community has probed into the biological validation of its extracts and isolated compounds including the gingerols, shogaols, zingiberene, and zingerone, through in-vitro and in-vivo studies. Nonetheless, an updated compilation of these data together with a deep mechanistic approach is yet to be provided. Accordingly, this review highlights the mechanisms and therapeutics of ginger and its bioactive compounds focused on a cancer context and these evidence are based on the (i) cytotoxic effect against cancer cell lines, (ii) enzyme inhibitory action, (iii) combination therapy with chemotherapeutic and phenolic compounds, (iv) possible links to the microbiome and (v) the use of nano-formulations of ginger bioactive compounds as a more effective drug delivery strategy in cancer therapy.
    Matched MeSH terms: Nanoparticles/chemistry
  8. Fulltext Green biosynthesis of silver nanoparticles using Curcuma longa tuber powder
    Shameli K, Ahmad MB, Zamanian A, Sangpour P, Shabanzadeh P, Abdollahi Y, et al.
    Int J Nanomedicine, 2012;7:5603-10.
    PMID: 23341739 DOI: 10.2147/IJN.S36786
    Green synthesis of noble metal nanoparticles is a vastly developing area of research. Metallic nanoparticles have received great attention from chemists, physicists, biologists, and engineers who wish to use them for the development of a new-generation of nanodevices. In this study, silver nanoparticles were biosynthesized from aqueous silver nitrate through a simple and eco-friendly route using Curcuma longa tuber-powder extracts, which acted as a reductant and stabilizer simultaneously. Characterizations of nanoparticles were done using different methods, which included ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray fluorescence spectrometry, and Fourier-transform infrared spectroscopy. The ultraviolet-visible spectrum of the aqueous medium containing silver nanoparticles showed an absorption peak at around 415 nm. Transmission electron microscopy showed that mean diameter and standard deviation for the formation of silver nanoparticles was 6.30 ± 2.64 nm. Powder X-ray diffraction showed that the particles are crystalline in nature, with a face-centered cubic structure. The most needed outcome of this work will be the development of value-added products from C. longa for biomedical and nanotechnology-based industries.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  9. Evaluation of in vitro efficacy of docetaxel-loaded calcium carbonate aragonite nanoparticles (DTX-CaCO3NP) on 4T1 mouse breast cancer cell line
    Hammadi NI, Abba Y, Hezmee MNM, Razak ISA, Kura AU, Zakaria ZAB
    In Vitro Cell Dev Biol Anim, 2017 Dec;53(10):896-907.
    PMID: 28916966 DOI: 10.1007/s11626-017-0197-3
    Cockle shell-derived calcium carbonate nanoparticles have shown promising potentials as slow drug-releasing compounds in cancer chemotherapy. In this study, we evaluated the in vitro efficacy of docetaxel (DTX)-loaded CaCO3NP on 4T1 cell line. This was achieved by evaluating the following: cytotoxicity using MTT assay, fluorescence imaging, apoptosis with Annexin V assay, cell cycle analysis, scanning (SEM) and transmission electron microscopy (TEM), and scratch assay. Based on the results, DTX-CaCO3NP with a DTX concentration of 0.5 μg/mL and above had comparable cytotoxic effects with free DTX at 24 h, while all concentrations had similar cytotoxic effect on 4T1 cells at 48 and 72 h. Fluorescence and apoptosis assay showed a higher (p 
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  10. Fulltext A pH-sensitive, biobased calcium carbonate aragonite nanocrystal as a novel anticancer delivery system
    Shafiu Kamba A, Ismail M, Tengku Ibrahim TA, Zakaria ZA
    Biomed Res Int, 2013;2013:587451.
    PMID: 24324966 DOI: 10.1155/2013/587451
    The synthesised biobased calcium carbonate nanocrystals had demonstrated to be an effective carrier for delivery of anticancer drug doxorubicin (DOX). The use of these nanocrystals displayed high levels of selectivity and specificity in achieving effective cancer cell death without nonspecific toxicity. These results confirmed that DOX was intercalated into calcium carbonate nanocrystals at high loading and encapsulation efficiency (4.8 and 96%, resp.). The CaCO₃/DOX nanocrystals are relatively stable at neutral pH (7.4), resulting in slow release, but the nanocrystals progressively dissociated in acidic pH (4.8) regimes, triggering faster release of DOX. The CaCO₃/DOX nanocrystals exhibited high uptake by MDA MB231 breast cancer cells and a promising potential delivery of DOX to target cells. In vitro chemosensitivity using MTT, modified neutral red/trypan blue assay, and LDH on MDA MB231 breast cancer cells revealed that CaCO₃/DOX nanocrystals are more sensitive and gave a greater reduction in cell growth than free DOX. Our findings suggest that CaCO₃ nanocrystals hold tremendous promise in the areas of controlled drug delivery and targeted cancer therapy.
    Matched MeSH terms: Nanoparticles/chemistry
  11. Fulltext Osteoblasts growth behaviour on bio-based calcium carbonate aragonite nanocrystal
    Shafiu Kamba A, Zakaria ZA
    Biomed Res Int, 2014;2014:215097.
    PMID: 24734228 DOI: 10.1155/2014/215097
    Calcium carbonate (CaCO3) nanocrystals derived from cockle shells emerge to present a good concert in bone tissue engineering because of their potential to mimic the composition, structure, and properties of native bone. The aim of this study was to evaluate the biological response of CaCO3 nanocrystals on hFOB 1.19 and MC3T3 E-1 osteoblast cells in vitro. Cell viability and proliferation were assessed by MTT and BrdU assays, and LDH was measured to determine the effect of CaCO3 nanocrystals on cell membrane integrity. Cellular morphology was examined by SEM and fluorescence microscopy. The results showed that CaCO3 nanocrystals had no toxic effects to some extent. Cell proliferation, alkaline phosphatase activity, and protein synthesis were enhanced by the nanocrystals when compared to the control. Cellular interactions were improved, as indicated by SEM and fluorescent microscopy. The production of VEGF and TGF-1 was also affected by the CaCO3 nanocrystals. Therefore, bio-based CaCO3 nanocrystals were shown to stimulate osteoblast differentiation and improve the osteointegration process.
    Matched MeSH terms: Nanoparticles/chemistry*
  12. Fulltext In vitro delivery and controlled release of Doxorubicin for targeting osteosarcoma bone cancer
    Kamba SA, Ismail M, Hussein-Al-Ali SH, Ibrahim TA, Zakaria ZA
    Molecules, 2013 Aug 30;18(9):10580-98.
    PMID: 23999729 DOI: 10.3390/molecules180910580
    Drug delivery systems are designed to achieve drug therapeutic index and enhance the efficacy of controlled drug release targeting with specificity and selectivity by successful delivery of therapeutic agents at the desired sites without affecting the non-diseased neighbouring cells or tissues. In this research, we developed and demonstrated a bio-based calcium carbonate nanocrystals carrier that can be loaded with anticancer drug and selectively deliver it to cancer cells with high specificity by achieving the effective osteosarcoma cancer cell death without inducing specific toxicity. The results showed pH sensitivity of the controlled release characteristics of the drug at normal physiological pH 7.4 with approximately 80% released within 1,200 min but when exposed pH 4.8 the corresponding 80% was released in 50 min. This study showed that the DOX-loaded CaCO₃ nanocrystals have promising applications in delivery of anticancer drugs.
    Matched MeSH terms: Nanoparticles/chemistry
  13. Formulation of a Sustained Release Docetaxel Loaded Cockle Shell-Derived Calcium Carbonate Nanoparticles against Breast Cancer
    Hammadi NI, Abba Y, Hezmee MNM, Razak ISA, Jaji AZ, Isa T, et al.
    Pharm Res, 2017 06;34(6):1193-1203.
    PMID: 28382563 DOI: 10.1007/s11095-017-2135-1
    PURPOSE: Here, we explored the formulation of a calcium carbonate nanoparticle delivery system aimed at enhancing docetaxel (DTX) release in breast cancer.

    METHODS: The designed nano- anticancer formulation was characterized thorough X-ray diffraction (XRD), Fourier transformed infrared (FTIR), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) and Brunauer-Emmett-Teller (BET) methods. The nano- anticancer formulation (DTX- CaCO3NP) was evaluated for drug delivery properties thorough in vitro release study in human body simulated solution at pH 7.4 and intracellular lysosomal pH 4.8.

    RESULTS: Characterization revealed the successful synthesis of DTX- CaCO3NP, which had a sustained release at pH 7.4. TEM showed uniformly distributed pleomorphic shaped pure aragonite particles. The highest entrapment efficiency (96%) and loading content (11.5%) were obtained at docetaxel to nanoparticles ratio of 1:4. The XRD patterns revealed strong crystallizations in all the nanoparticles formulation, while FTIR showed chemical interactions between the drug and nanoparticles with negligible positional shift in the peaks before and after DTX loading. BET analysis showed similar isotherms before and after DTX loading. The designed DTX- CaCO3NP had lower (p  0.05) effects at 48 h and 72 h. However, the DTX- CaCO3NP released less than 80% of bond DTX at 48 and 72 h but showed comparable effects with free DTX.

    CONCLUSIONS: The results showed that the developed DTX- CaCO3NP released DTX slower at pH 7.4 and had comparable cytotoxicity with free DTX at 48 and 72 h in MCF-7 cells.

    Matched MeSH terms: Nanoparticles/chemistry*
  14. Fulltext Development of drug delivery systems based on layered hydroxides for nanomedicine
    Barahuie F, Hussein MZ, Fakurazi S, Zainal Z
    Int J Mol Sci, 2014;15(5):7750-86.
    PMID: 24802876 DOI: 10.3390/ijms15057750
    Layered hydroxides (LHs) have recently fascinated researchers due to their wide application in various fields. These inorganic nanoparticles, with excellent features as nanocarriers in drug delivery systems, have the potential to play an important role in healthcare. Owing to their outstanding ion-exchange capacity, many organic pharmaceutical drugs have been intercalated into the interlayer galleries of LHs and, consequently, novel nanodrugs or smart drugs may revolutionize in the treatment of diseases. Layered hydroxides, as green nanoreservoirs with sustained drug release and cell targeting properties hold great promise of improving health and prolonging life.
    Matched MeSH terms: Nanoparticles/chemistry*
  15. Fulltext Synthesis of nanocrystalline SnO(x) (x = 1-2) thin film using a chemical bath deposition method with improved deposition time, temperature and pH
    Ebrahimiasl S, Yunus WM, Kassim A, Zainal Z
    Sensors (Basel), 2011;11(10):9207-16.
    PMID: 22163690 DOI: 10.3390/s111009207
    Nanocrystalline SnO(x) (x = 1-2) thin films were prepared on glass substrates by a simple chemical bath deposition method. Triethanolamine was used as complexing agent to decrease time and temperature of deposition and shift the pH of the solution to the noncorrosive region. The films were characterized for composition, surface morphology, structure and optical properties. X-ray diffraction analysis confirms that SnO(x) thin films consist of a polycrystalline structure with an average grain size of 36 nm. Atomic force microscopy studies show a uniform grain distribution without pinholes. The elemental composition was evaluated by energy dispersive X-ray spectroscopy. The average O/Sn atomic percentage ratio is 1.72. Band gap energy and optical transition were determined from optical absorbance data. The film was found to exhibit direct and indirect transitions in the visible spectrum with band gap values of about 3.9 and 3.7 eV, respectively. The optical transmittance in the visible region is 82%. The SnO(x) nanocrystals exhibit an ultraviolet emission band centered at 392 nm in the vicinity of the band edge, which is attributed to the well-known exciton transition in SnO(x). Photosensitivity was detected in the positive region under illumination with white light.
    Matched MeSH terms: Nanoparticles/chemistry*
  16. Synthesis of 4-chlorophenoxyacetate-zinc-aluminium-layered double hydroxide nanocomposite: physico-chemical and controlled release properties
    Hussein MZ, Sarijo SH, Yahaya AH, Zainal Z
    J Nanosci Nanotechnol, 2007 Aug;7(8):2852-62.
    PMID: 17685307
    Layered organic-inorganic hybrid nanocomposite material was synthesised using 4-chlorophenoxyacetate (4CPA) as guest anion intercalated into the Zn-Al layered double hydroxide inorganic host by direct co-precipitation method at pH = 7.5 and Zn to Al molar ratio of 4. Both PXRD and FTIR results confirmed that the 4CPA was successfully intercalated into the Zn-AI-LDH interlayer. As a result, a well-ordered nanolayered organic-inorganic hybrid nanocomposite, with the expansion of the basal spacing from 8.9 angstroms in the layered double hydroxide to 20.1 angstroms in the resulting nanocomposite was observed. The FTIR spectrum of the nanocomposite (ZAC) showed that it composed spectral features of Zn-AI-LDH (ZAL) and 4CPA. The nanocomposites synthesized in this work are of mesoporous-type containing 39.8% (w/w) of 4CPA with mole fraction of Al3+ in the inorganic brucite-like layers (xAI) of 0.224. The release studies showed a rapid release of the 4CPA for the first 600 min, and more sustained thereafter. The total amount of 4CPA released from the nanocomposite interlayer into the aqueous solution were 21%, 66%, and 72% in 0.0001, 0.00025, and 0.0005 M sodium carbonate, respectively. In distilled water, about 75, 35, and 57% of 4CPA could be released in 1000 min, when the pH of the release media was set at 3, 6.25, and 12, respectively. In comparison with a structurally similar organic moiety with one more chlorine atom at the 2-position of the aromatic ring, namely 2,4-dichlorophenoxyacetate (24D), the 4CPA showed a slower release rate. The slightly bulkier organic moiety of 24D together with the presence of chlorine atom at the 2-position presumably had contributed to its higher release rate, and it seems that these factors may be exploited for tuning the release rate of intercalated guest anions with similar properties. This study suggests that layered double hydroxide can be used as a carrier for an active agent and the chemical structure of the intercalated moiety can be used to tune the desired release kinetics of the beneficial agent.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
  17. Fulltext Conversion of lignocellulosic biomass to nanocellulose: structure and chemical process
    Lee HV, Hamid SB, Zain SK
    ScientificWorldJournal, 2014;2014:631013.
    PMID: 25247208 DOI: 10.1155/2014/631013
    Lignocellulosic biomass is a complex biopolymer that is primary composed of cellulose, hemicellulose, and lignin. The presence of cellulose in biomass is able to depolymerise into nanodimension biomaterial, with exceptional mechanical properties for biocomposites, pharmaceutical carriers, and electronic substrate's application. However, the entangled biomass ultrastructure consists of inherent properties, such as strong lignin layers, low cellulose accessibility to chemicals, and high cellulose crystallinity, which inhibit the digestibility of the biomass for cellulose extraction. This situation offers both challenges and promises for the biomass biorefinery development to utilize the cellulose from lignocellulosic biomass. Thus, multistep biorefinery processes are necessary to ensure the deconstruction of noncellulosic content in lignocellulosic biomass, while maintaining cellulose product for further hydrolysis into nanocellulose material. In this review, we discuss the molecular structure basis for biomass recalcitrance, reengineering process of lignocellulosic biomass into nanocellulose via chemical, and novel catalytic approaches. Furthermore, review on catalyst design to overcome key barriers regarding the natural resistance of biomass will be presented herein.
    Matched MeSH terms: Nanoparticles/chemistry*
  18. Effects of anodizing parameters and heat treatment on nanotopographical features, bioactivity, and cell culture response of additively manufactured porous titanium
    Amin Yavari S, Chai YC, Böttger AJ, Wauthle R, Schrooten J, Weinans H, et al.
    Mater Sci Eng C Mater Biol Appl, 2015 Jun;51:132-8.
    PMID: 25842117 DOI: 10.1016/j.msec.2015.02.050
    Anodizing could be used for bio-functionalization of the surfaces of titanium alloys. In this study, we use anodizing for creating nanotubes on the surface of porous titanium alloy bone substitutes manufactured using selective laser melting. Different sets of anodizing parameters (voltage: 10 or 20V anodizing time: 30min to 3h) are used for anodizing porous titanium structures that were later heat treated at 500°C. The nanotopographical features are examined using electron microscopy while the bioactivity of anodized surfaces is measured using immersion tests in the simulated body fluid (SBF). Moreover, the effects of anodizing and heat treatment on the performance of one representative anodized porous titanium structures are evaluated using in vitro cell culture assays using human periosteum-derived cells (hPDCs). It has been shown that while anodizing with different anodizing parameters results in very different nanotopographical features, i.e. nanotubes in the range of 20 to 55nm, anodized surfaces have limited apatite-forming ability regardless of the applied anodizing parameters. The results of in vitro cell culture show that both anodizing, and thus generation of regular nanotopographical feature, and heat treatment improve the cell culture response of porous titanium. In particular, cell proliferation measured using metabolic activity and DNA content was improved for anodized and heat treated as well as for anodized but not heat-treated specimens. Heat treatment additionally improved the cell attachment of porous titanium surfaces and upregulated expression of osteogenic markers. Anodized but not heat-treated specimens showed some limited signs of upregulated expression of osteogenic markers. In conclusion, while varying the anodizing parameters creates different nanotube structure, it does not improve apatite-forming ability of porous titanium. However, both anodizing and heat treatment at 500°C improve the cell culture response of porous titanium.
    Matched MeSH terms: Metal Nanoparticles/chemistry
  19. Fulltext QuadraPure-supported palladium nanocatalysts for microwave-promoted Suzuki cross-coupling reaction under aerobic condition
    Liew KH, Loh PL, Juan JC, Yarmo MA, Yusop RM
    ScientificWorldJournal, 2014;2014:796196.
    PMID: 25054185 DOI: 10.1155/2014/796196
    Cross-linked resin-captured palladium (XL-QPPd) was readily prepared by simple physical adsorption onto the high loading QuadraPure macroporous resin and a subsequent reduction process. To enhance the mechanical stability, entrapped palladium nanocatalysts were cross-linked with succinyl chloride. Both transmission electron microscopy images and X-ray diffraction analysis revealed that the palladium nanoparticles were well dispersed with diameters ranging in 4-10 nm. The catalyst performed good catalytic activity in microwave-promoted Suzuki cross-coupling reactions in water under aerobic condition with mild condition by using various aryl halides and phenylboronic acid. In addition, the catalyst showed an excellent recyclability without significant loss of catalytic activity.
    Matched MeSH terms: Nanoparticles/chemistry*
  20. In Vitro Anticancer Activity of Au, Ag Nanoparticles Synthesized Using Commelina nudiflora L. Aqueous Extract Against HCT-116 Colon Cancer Cells
    Kuppusamy P, Ichwan SJ, Al-Zikri PN, Suriyah WH, Soundharrajan I, Govindan N, et al.
    Biol Trace Elem Res, 2016 Oct;173(2):297-305.
    PMID: 26961292 DOI: 10.1007/s12011-016-0666-7
    Recently, metal nanoparticles have been getting great medical and social interests due to their potential physico-chemical properties such as higher affinity, low molecular weight, and larger surface area. The biosynthesized gold and silver nanoparticles are spherical, triangular in shape with an average size of 24-150 nm as reported in our earlier studies. The biological properties of synthesized gold and silver nanoparticles are demonstrated in this paper. The different in vitro assays such as MTT, flow cytometry, and reverse transcription polymerase chain reaction (RT-qPCR) techniques were used to evaluate the in vitro anticancer properties of synthesized metal nanoparticles. The biosynthesized gold and silver nanoparticles have shown reduced cell viability and increased cytotoxicity in HCT-116 colon cancer cells with IC50 concentration of 200 and 100 μg/ml, respectively. The flow cytometry experiments revealed that the IC50 concentrations of gold and silver nanoparticle-treated cells that have significant changes were observed in the sub-G1 cell cycle phase compared with the positive control. Additionally, the relative messenger RNA (mRNA) gene expressions of HCT-116 cells were studied by RT-qPCR techniques. The pro-apoptotic genes such as PUMA (++), Caspase-3 (+), Caspase-8 (++), and Caspase-9 (++) were upregulated in the treated HCT-116 cells compared with cisplatin. Overall, these findings have proved that the synthesized gold and silver nanoparticles could be potent anti-colon cancer drugs.
    Matched MeSH terms: Metal Nanoparticles/chemistry*
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