Displaying publications 81 - 100 of 832 in total

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  1. Fulltext Fabrication and Thermo-Electro and Mechanical Properties Evaluation of Helical Multiwall Carbon Nanotube-Carbon Fiber/Epoxy Composite Laminates
    Ali A, Andriyana A, Hassan SBA, Ang BC
    Polymers (Basel), 2021 Apr 29;13(9).
    PMID: 33947012 DOI: 10.3390/polym13091437
    The development of advanced composite materials has taken center stage because of its advantages over traditional materials. Recently, carbon-based advanced additives have shown promising results in the development of advanced polymer composites. The inter- and intra-laminar fracture toughness in modes I and II, along with the thermal and electrical conductivities, were investigated. The HMWCNTs/epoxy composite was prepared using a multi-dispersion method, followed by uniform coating at the mid-layers of the CF/E prepregs interface using the spray coating technique. Analysis methods, such as double cantilever beam (DCB) and end notched flexure (ENF) tests, were carried out to study the mode I and II fracture toughness. The surface morphology of the composite was analyzed using field emission scanning electron microscopy (FESEM). The DCB test showed that the fracture toughness of the 0.2 wt.% and 0.4 wt.% HMWCNT composite laminates was improved by 39.15% and 115.05%, respectively, compared with the control sample. Furthermore, the ENF test showed that the mode II interlaminar fracture toughness for the composite laminate increased by 50.88% and 190%, respectively. The FESEM morphology results confirmed the HMWCNTs bridging at the fracture zones of the CF/E composite and the improved interlaminar fracture toughness. The thermogravimetric analysis (TGA) results demonstrated a strong intermolecular bonding between the epoxy and HMWCNTs, resulting in an improved thermal stability. Moreover, the differential scanning calorimetry (DSC) results confirmed that the addition of HMWCNT shifted the Tg to a higher temperature. An electrical conductivity study demonstrated that a higher CNT concentration in the composite laminate resulted in a higher conductivity improvement. This study confirmed that the demonstrated dispersion technique could create composite laminates with a strong interfacial bond interaction between the epoxy and HMWCNT, and thus improve their properties.
    Matched MeSH terms: Polymers
  2. Unusual poly(3-hydroxyalkanoate) (PHA) biosynthesis behavior of Pseudomonas putida Bet001 and Delftia tsuruhatensis Bet002 isolated from palm oil mill effluent
    Razaif-Mazinah MRM, Anis SNS, Harun HI, Rashid KA, Annuar MSM
    Biotechnol Appl Biochem, 2017 Mar;64(2):259-269.
    PMID: 26800648 DOI: 10.1002/bab.1482
    Pseudomonas putida Bet001 and Delftia tsuruhatensis Bet002, isolated from palm oil mill effluent, accumulated poly(3-hydroxyalkanoates) (PHAs) when grown on aliphatic fatty acids, sugars, and glycerol. The substrates were supplied at 20:1 C/N mole ratio. Among C-even n-alkanoic acids, myristic acid gave the highest PHA content 26 and 28 wt% in P. putida and D. tsuruhatensis, respectively. Among C-odd n-alkanoic acids, undecanoic gave the highest PHA content at 40 wt% in P. putida and 46 wt% in D. tsuruhatensis on pentadecanoic acid. Sugar and glycerol gave <10 wt% of PHA content for both bacteria. Interestingly, D. tsuruhatensis accumulated both short- and medium-chain length PHA when supplied with n-alkanoic acids ranging from octanoic to lauric, sucrose, and glycerol with 3-hydroxybutyrate as the major monomer unit. In P. putida, the major hydroxyalkanoates unit was 3-hydroxyoctanoate and 3-hydroxydecanoate when grown on C-even acids. Conversely, 3-hydroxyheptanoate, 3-hydrxoynonanoate, and 3-hydroxyundecanoate were accumulated with C-odd acids. Weight-averaged molecular weight (Mw ) was in the range of 53-81 kDa and 107-415 kDa for P. putida and D. tsuruhatensis, respectively. Calorimetric analyses indicated that both bacteria synthesized semicrystalline polymer with good thermal stability with degradation temperature (Td ) ranging from 178 to 282 °C.
    Matched MeSH terms: Polymers
  3. Guest-host Relationship of Cyclodextrin and its Pharmacological Benefits
    Alshati F, Alahmed TAA, Sami F, Ali MS, Majeed S, Murtuja S, et al.
    Curr Pharm Des, 2023;29(36):2853-2866.
    PMID: 37946351 DOI: 10.2174/0113816128266398231027100119
    Many methods, including solid dispersion, micellization, and inclusion complexes, have been employed to increase the solubility of potent drugs. Beta-cyclodextrin (βCD) is a cyclic oligosaccharide consisting of seven glucopyranoside molecules, and is a widely used polymer for formulating soluble inclusion complexes of hydrophobic drugs. The enzymatic activity of Glycosyltransferase or α-amylase converts starch or its derivatives into a mixture of cyclodextrins. The βCD units are characterized by α -(1-4) glucopyranose bonds. Cyclodextrins possess certain properties that make them very distinctive because of their toroidal or truncated cage-like supramolecular configurations with multiple hydroxyl groups at each end. This allowed them to encapsulate hydrophobic compounds by forming inclusion complexes without losing their solubility in water. Chemical modifications and newer derivatives, such as methylated βCD, more soluble hydroxyl propyl methyl βCD, and sodium salts of sulfobutylether-βCD, known as dexolve® or captisol®, have envisaged the use of CDs in various pharmaceutical, medical, and cosmetic industries. The successful inclusion of drug complexes has demonstrated improved solubility, bioavailability, drug resistance reduction, targeting, and penetration across skin and brain tissues. This review encompasses the current applications of β-CDs in improving the disease outcomes of antimicrobials and antifungals as well as anticancer and anti-tubercular drugs.
    Matched MeSH terms: Polymers
  4. Fulltext Potential of electron beam irradiated HDPE/EPR blend as shoes sole
    Husniyah Aliyah, L., Anuar, H.
    Movement Health & Exercise, 2014;3(1):49-56.
    MyJurnal
    This study focuses on the mechanical effect of different composition of polymer blend. Polymer blend of high density polyethylene (HDPE) and ethylene propylene rubber (EPR) were selected and varied by three different compositions which are 70:30, 50:50 and 30:70. HDPE-EPR blend is believed to be the best material for sole shoe. In which, HDPE has good flexibility while, EPR can maintain optimum performance at high and low temperature as well as provide better gripping characteristic that suits for insole and outsole sport shoe. On the other hand, the time efficiency of electron beam radiation on these polymer blends helps in improving the croslinking of HDPE-EPR blend. The aim of this paper was to find the optimum composition of electron beam irradiated polymer blends for sole shoes especially in sports application. These irradiated polymer blends were produced by melt blending, underwent compression moulding and then were irradiated by electron beam at 100 kGy/s. Mechanical test of tensile and hardness test were investigated and the morphology of the failure fracture was analysed by field emission scanning electron microscopy (FESEM). The polymer blend with 70% of HDPE and 30% of EPR showed the optimum result of tensile strength, tensile modulus and hardness as well as ductile failure image.
    Matched MeSH terms: Polymers
  5. Fulltext Screening of Electrospray-operating Parameters in the Production of Alginate-Royal Jelly Microbeads Using Factorial Design
    Shaiqah MR, Salahuddin HM, Afiful Huda AYA, Izzuddin M, Nur Shafiq NIM, Nur Hakimah MA, et al.
    J Pharm Bioallied Sci, 2020 Nov;12(Suppl 2):S703-S706.
    PMID: 33828364 DOI: 10.4103/jpbs.JPBS_249_19
    Introduction: Royal jelly (RJ) has been consumed as food or as a supplement because of its high nutritional and medicinal values. A fresh harvested RJ is yellowish to whitish in color and contains proteins, free amino acids, lipids, vitamins, and sugar. Without proper storage conditions, such as at 4°C, the color of RJ changes to much darker yellow and produces a rancid smell. To prolong its shelf life, RJ is usually mixed with honey. Alginate, a natural and edible polymer derived from seaweed, is commonly used to encapsulate drugs and food due to its ability to form gels by reacting with divalent cations. However, there is a lack of research on the microencapsulation of RJ in alginate using electrospray. The electrospray technique has the advantage in producing consistent size and shape of alginate microbeads under optimum parameters.

    Aim: This research aimed to optimize electrospray-operating parameters in producing alginate-RJ microbeads.

    Materials and Methods: Optimization of alginate-RJ microbeads electrospray parameters was carried out using 24 factorial design with three center points (19 runs). The studied parameters were flow rate, high voltage, nozzle size, and tip-to-collector distance, whereas the responses were particle size, particle size distribution, and sphericity factor. The responses of each run were analyzed using Design-Expert software.

    Results: Nozzle size is a significant parameter that influences the particle size. Flow rate is a significant parameter influencing the sphericity factor.

    Conclusion: Screening of the electrospray-operating parameters paves the way in determining the significant parameters and their design space to produce consistent alginate-RJ microbeads.

    Matched MeSH terms: Polymers
  6. Self-assembled micelles loaded with itraconazole as anti-Acanthamoeba nano-formulation
    Rao K, Abdullah M, Ahmed U, Wehelie HI, Shah MR, Siddiqui R, et al.
    Arch Microbiol, 2024 Mar 04;206(4):134.
    PMID: 38433145 DOI: 10.1007/s00203-024-03854-3
    Acanthamoeba castellanii are opportunistic pathogens known to cause infection of the central nervous system termed: granulomatous amoebic encephalitis, that mostly effects immunocompromised individuals, and a sight threatening keratitis, known as Acanthamoeba keratitis, which mostly affects contact lens wearers. The current treatment available is problematic, and is toxic. Herein, an amphiphilic star polymer with AB2 miktoarms [A = hydrophobic poly(ℇ-Caprolacton) and B = hydrophilic poly (ethylene glycol)] was synthesized by ring opening polymerization and CuI catalyzed azide-alkyne cycloaddition. Characterization by 1H and 13C NMR spectroscopy, size-exclusion chromatography and fluorescence spectroscopy was accomplished. The hydrophobic drug itraconazole (ITZ) was incorporated in self-assembled micellar structure of AB2 miktoarms through co-solvent evaporation. The properties of ITZ loaded (ITZ-PCL-PEG2) and blank micelles (PCL-PEG2) were investigated through zeta sizer, scanning electron microscopy and Fourier-transform infrared spectroscopy. Itraconazole alone (ITZ), polymer (DPB-PCL), empty polymeric micelles (PCL-PEG2) alone, and itraconazole loaded in polymeric micelles (ITZ-PCL-PEG2) were tested for anti-amoebic potential against Acanthamoeba, and the cytotoxicity on human cells were determined. The polymer was able to self-assemble in aqueous conditions and exhibited low value for critical micelle concentration (CMC) 0.05-0.06 µg/mL. The maximum entrapment efficiency of ITZ was 68%. Of note, ITZ, DPB, PCL-PEG2 and ITZ-PCL-PEG2 inhibited amoebae trophozoites by 37.34%, 36.30%, 35.77%, and 68.24%, respectively, as compared to controls. Moreover, ITZ-PCL-PEG2 revealed limited cytotoxicity against human keratinocyte cells. These results are indicative that ITZ-PCL-PEG2 micelle show significantly better anti-amoebic effects as compared to ITZ alone and thus should be investigated further in vivo to determine its clinical potential.
    Matched MeSH terms: Polymers
  7. Smart electrical bi-layers lipopeptides: Novel peptidic chains like zigzag map esterified with phospho-glyceride as mono-layer moieties capable in forming a meso-sphere- envelop with scaffold- ability to cellular impurities
    Saadi S, Saari N, Abdulkarim MS, Ghazali HM, Anwar F
    J Control Release, 2018 03 28;274:93-101.
    PMID: 29031897 DOI: 10.1016/j.jconrel.2017.10.011
    Cell impurities are an emerging nucleating molecular barriers having the capability in disordering the metabolic chain reactions of proteolysis, glycolysis and lipolysis. Their massive effects induced by copolymer crystal growth in compaction with metal and mineral transients are extended as well as in damaging DNA and mRNA structure motif and other molecular assembly e.g. histones structure unites. Their polycrystalline packing modes, polydispersity and their tendency to surface and interface adhesion prompted us in structuring scaffold biomaterials enriched with biopeptides, layered by phospho-glycerides ester-forms. The interface tension of the formed map is flexible and dependent to the surface exposure and its collapse modes to the surrounding molecular ligands. Thus, the attempts in increasing surface exposure e.g. the viscoelastic of structured lipopeptides and types of formed network structures interplays an extra- conjugating biomolecules having a least cytotoxicity effects to cells constituents. Disulfides molecules are selected to be the key regulatory element in rejoining both lipidic and proteic moieties by disordering atoms status via chemical ionization using organic catalyst. The insertion of methionine based peptidic chain at the lateral surfaces of scaffold biomaterials enhances the electron-meta-static motions by raising a molecular disordering status at distinct regions of the map e.g. epimerization into a nonpolar side that helps the chemical conjunction of disulfide groups with the esterified phosphoglycerides mono-layers. These effects in turn are accomplished by the formation of meso-sphere nonpolar- vesicles. The oxidation of disulfide group would alter the ordering of initial molecules by raising a newly molecular disorders to the map with high polarity to surface regions. In the same time indicates a continuation in the crystallization growth factor via a low chemical lesions between the impurities and a supersaturation in the intra-atomic distances with maximum cross linking to the deformed ligand with scaffold biomaterials.
    Matched MeSH terms: Polymers
  8. Fulltext Shelf-life, bioburden, water and oxygen permeability studies of laser welded SEBS/PP blended polymer
    Sundera Murthe S, Sreekantan S, Mydin RBSMN, Vasudevan M, Appaturi JN
    Sci Rep, 2023 Sep 01;13(1):14379.
    PMID: 37658068 DOI: 10.1038/s41598-023-41477-8
    The most common material used for blood bags is PVC, which requires the addition of DEHP to increase its flexibility. DEHP is known to cross the polymer barrier and move into the stored blood and, ultimately, the patient's bloodstream. In this work, an alternative prototype composed of SEBS/PP was fabricated through blow-moulding and compared with the commercially available PVC-based blood bag which was designated as the control. The blow-moulded sample layers were welded together using CO2 lasers and optimized to obtain complete sealing of the sides. The samples' performance characteristics were analyzed using water permeability, oxygen permeability, shelf-life, and bioburden tests. The SEBS/PP sample exhibited the highest oxygen permeability rate of 1486.6 cc/m2/24 h after 40 days of ageing, indicating that the sample is conducive for red blood cell (RBC) respiration. On the other hand, the SEBS/PP sample showcased a lower water permeability rate of 0.098 g/h m2 after 40 days of aging, indicating a high-water barrier property and thus preventing water loss during storage. In comparison, the oxygen and water permeability rates of PVC-DEHP were found to be distinctly lower in performance (662.7 cc/m2/24 h and 0.221 g/h m2, respectively). In addition, shelf-life analyses revealed that after 40 days of ageing, polymer samples exhibited no visual damage or degradation. The optimal parameters to obtain adequate welding of the SEBS/PP were determined to be power of 60% (18 W), speed of 70 in/sec and 500 Pulse Per Inch (PPI). Furthermore, the bioburden estimates of SEBS/PP of 115 CFU are markedly lower compared to the bioburden estimate of PVC-DEHP of 213 CFU. The SEBS/PP prototype can potentially be an effective alternative to PVC-based blood bags, particularly for high-risk patients in order to reduce the likelihood of medical issues.
    Matched MeSH terms: Polymers
  9. Alginate-based bipolymeric-nanobioceramic composite matrices for sustained drug release
    Hasnain MS, Nayak AK, Singh M, Tabish M, Ansari MT, Ara TJ
    Int J Biol Macromol, 2016 Feb;83:71-7.
    PMID: 26608007 DOI: 10.1016/j.ijbiomac.2015.11.044
    Alginate-based bipolymeric-nanobioceramic composite matrices for sustained drug release were developed through incorporation of nano-hydroxyapatite [nHAp] powders within ionotropically-gelled calcium ion-induced alginate-poly (vinyl pyrrolidone) blends polymeric systems. nHAp powders were synthesized by precipitation technique using calcium hydroxide [Ca(OH)2] and orthophosphoric acid [H3PO4] as raw materials. The average particle size of these was synthesized. nHAp powders was found as 19.04 nm and used to prepare nHAp-alginate-PVP beads containing DS. These beads exhibited drug entrapment efficiency (%) of 65.82±1.88 to 94.45±3.72% and average bead sizes of 0.98±0.07 to 1.23±0.15 mm. These beads were characterized by scanning electron microscopy (SEM) and Fourier transform-infra red (FTIR) spectroscopy analyses. Various nHAp-alginate-PVP beads containing DS exhibited prolonged sustained drug release and followed the Koresmeyer-Peppas model of drug release (R2=0.9908-0.9978) with non-Fickian release (anomalous transport) mechanism (n=0.73-0.84) for drug release over 8 h.
    Matched MeSH terms: Polymers/chemistry*
  10. Fulltext Crystal structure and Hirshfeld surface analysis of a chalcone derivative: (E)-3-(4-fluoro-phen-yl)-1-(4-nitro-phen-yl)prop-2-en-1-one
    Wong QA, Chia TS, Kwong HC, Chidan Kumar CS, Quah CK, Arafath MA
    Acta Crystallogr E Crystallogr Commun, 2019 Jan 01;75(Pt 1):53-57.
    PMID: 30713733 DOI: 10.1107/S2056989018017450
    The mol-ecular structure of the title chalcone derivative, C15H10FNO3, is nearly planar and the mol-ecule adopts a trans configuration with respect to the C=C double bond. The nitro group is nearly coplanar with the attached benzene ring, which is nearly parallel to the second benzene ring. In the crystal, mol-ecules are connected by pairs of weak inter-molecular C-H⋯O hydrogen bonds into inversion dimers. The dimers are further linked by another C-H⋯O hydrogen bond and a C-H⋯F hydrogen bond into sheets parallel to (104). π-π inter-actions occur between the sheets, with a centroid-centroid distance of 3.8860 (11) Å. Hirshfeld surface analysis was used to investigate and qu-antify the inter-molecular inter-actions.
    Matched MeSH terms: Polymers
  11. Intestinal Obstruction Due to Super Absorbent Polymer Bead Ingestion in Children
    Govindarajan KK, Arasappan M
    J Coll Physicians Surg Pak, 2023 Feb;33(2):232-233.
    PMID: 36797637 DOI: 10.29271/jcpsp.2023.02.232
    Ingested foreign bodies (Fb) in children usually pass out in stools without any sequels. However, Fbs like open safety pins, button batteries, and super absorbent polymer (SAP) / jelly toys are associated with complications such as intestinal obstruction, and bowel perforation. Intestinal obstruction in children of uncertain nature should raise a suspicion of foreign body ingestion such as SAP, which may not be obvious at the initial presentation. The study reports two such children, outlining the presentation and management. Key Words: Children, Intestinal obstruction, Foreign body, Health hazard, Bilious vomit, Super absorbent polymer beads.
    Matched MeSH terms: Polymers
  12. Hydrous ferric oxide nanoparticles hosted porous polyethersulfone adsorptive membrane: chromium (VI) adsorptive studies and its applicability for water/wastewater treatment
    Abdullah N, Yusof N, Abu Shah MH, Wan Ikhsan SN, Ng ZC, Maji S, et al.
    Environ Sci Pollut Res Int, 2019 Jul;26(20):20386-20399.
    PMID: 31102226 DOI: 10.1007/s11356-019-05208-9
    In this present study, adsorptive membranes for Cr(VI) ion removal were prepared by blending polyethersulfone (PES) with hydrous ferric oxide (HFO) nanoparticles (NPs). The effects of HFO NPs to PES weight ratio (0-1.5) on the physicochemical properties of the resultant HFO/PES adsorptive membranes were investigated with respect to the surface chemistry and roughness as well as structural morphologies using different analytical instruments. The adsorptive performance of the HFO NPs/PES membranes was studied via batch adsorption experiments under various conditions by varying solution pH, initial concentration of Cr(VI), and contact time. The results showed that the membrane made of HFO/PES at a weight ratio of 1.0 exhibited the highest adsorption capacity which is 13.5 mg/g. Isotherm and kinetic studies revealed that the mechanism is best fitted to the Langmuir model and pseudo-second-order model. For filtration of Cr(VI), the best promising membranes showed improved water flux (629.3 L/m2 h) with Cr(VI) ion removal of 75%. More importantly, the newly developed membrane maintained the Cr(VI) concentration below the maximum contamination level (MCL) for up to 9 h.
    Matched MeSH terms: Polymers/chemistry
  13. Microplastic pollution in tropical estuary gastropods: Abundance, distribution and potential sources of Klang River estuary, Malaysia
    Zaki MRM, Zaid SHM, Zainuddin AH, Aris AZ
    Mar Pollut Bull, 2021 Jan;162:111866.
    PMID: 33256966 DOI: 10.1016/j.marpolbul.2020.111866
    Microplastics receive global attention due to its strong presence in marine and freshwater organisms. Yet, there are few studies on estuarine organisms. This baseline study evaluates the abundance and distribution of microplastics in the gastropods of a tropical estuary in Selangor, Malaysia. The abundance of microplastics ranged from 0.50 to 1.75 particles/g or from 0.25 to 0.88 particles/individual. The variation in microplastic distribution between the upper and lower estuary indicates that the microplastics originated from the urbanised area of the Klang River estuary. Microplastic sizes varied from 30 to 1850 μm, with the majority being between 300 and 1000 μm (57%). Characteristics of microplastics were dominant for fibres (91%) with black colour (50%). Polyethylene-propylene-diene (PE-PDM) and polyester were the main polymer materials. Assessing the contamination of gastropods by microplastics provides insight into the possibility of utilising gastropods as bioindicators that could be used for monitoring and baseline studies.
    Matched MeSH terms: Polymers
  14. FT-IR studies on interactions among components in hexanoyl chitosan-based polymer electrolytes
    Winie T, Arof AK
    Spectrochim Acta A Mol Biomol Spectrosc, 2006 Mar 1;63(3):677-84.
    PMID: 16157506
    Fourier transform infrared (FT-IR) spectroscopic studies have been undertaken to investigate the interactions among components in a system of hexanoyl chitosan-lithium trifluoromethanesulfonate (LiCF(3)SO(3))-diethyl carbonate (DEC)/ethylene carbonate (EC). LiCF(3)SO(3) interacts with the hexanoyl chitosan to form a hexanoyl chitosan-salt complex that results in the shifting of the N(COR)(2), CONHR and OCOR bands to lower wavenumbers. Interactions between EC and DEC with LiCF(3)SO(3) has been noted and discussed. Evidence of interaction between EC and DEC has been obtained experimentally. Studies on polymer-plasticizer spectra suggested that there is no interaction between the polymer host and plasticizers. Competition between plasticizer and polymer on associating with Li(+) ions was observed from the spectral data for gel polymer electrolytes. The obtained spectroscopic data has been correlated with the conductivity performance of hexanoyl chitosan-based polymer electrolytes.
    Matched MeSH terms: Polymers/chemistry*
  15. Vibrational studies of flexible solid polymer electrolyte based on PCL-EC incorporated with proton conducting NH4SCN
    Woo HJ, Arof AK
    Spectrochim Acta A Mol Biomol Spectrosc, 2016 May 15;161:44-51.
    PMID: 26945998 DOI: 10.1016/j.saa.2016.02.034
    A flexible solid polymer electrolyte (SPE) system based on poly(ε-caprolactone) (PCL), a FDA approved non-toxic and biodegradable material in the effort to lower environmental impact was prepared. Ammonium thiocyanate (NH4SCN) and ethylene carbonate (EC) were incorporated as the source of charge carriers and plasticizing agent, respectively. When 50wt.% of ethylene carbonate (EC) was added to PCL-NH4SCN system, the conductivity increased by two orders from of 3.94×10(-7)Scm(-1) to 3.82×10(-5)Scm(-1). Molecular vibrational analysis via infrared spectroscopy had been carried out to study the interaction between EC, PCL and NH4SCN. The relative percentage of free ions, ion pairs and ion aggregates was calculated quantitatively by deconvoluting the SCN(-) stretching mode (2030-2090cm(-1)). This study provides fundamental insight on how EC influences the free ion dissociation rate and ion mobility. The findings are also in good agreement to conductivity, differential scanning calorimetry and X-ray diffraction results. High dielectric constant value (89.8) of EC had made it an effective ion dissociation agent to dissociate both ion pairs and ion aggregates, thus contributing to higher number density of free ions. The incorporation of EC had made the polymer chains more flexible in expanding amorphous domain. This will facilitate the coupling synergy between ionic motion and polymer segmental motion. Possible new pathway through EC-NH4(+) complex sites for ions to migrate with shorter distance has been anticipated. This implies an easier ion migration route from one complex site to another.
    Matched MeSH terms: Polymers
  16. Improvement of N-phthaloylchitosan based gel polymer electrolyte in dye-sensitized solar cells using a binary salt system
    Yusuf SNF, Azzahari AD, Selvanathan V, Yahya R, Careem MA, Arof AK
    Carbohydr Polym, 2017 Feb 10;157:938-944.
    PMID: 27988011 DOI: 10.1016/j.carbpol.2016.10.032
    A binary salt system utilizing lithium iodide (LiI) as the auxiliary component has been introduced to the N-phthaloylchitosan (PhCh) based gel polymer electrolyte consisting of ethylene carbonate (EC), dimethylformamide (DMF), tetrapropylammonium iodide (TPAI), and iodine (I2) in order to improve the performance of dye-sensitized solar cell (DSSC) with efficiency of 6.36%, photocurrent density, JSC of 17.29mAcm-2, open circuit voltage, VOC of 0.59V and fill factor, FF of 0.62. This efficiency value is an improvement from the 5.00% performance obtained by the DSSC consisting of only TPAI single salt system. The presence of the LiI in addition to the TPAI improves the charge injection rates and increases the iodide contribution to the total conductivity and both factors contribute to the increase in efficiency of the DSSC. The interaction behavior between polymer-plasticizer-salt was thoroughly investigated using EIS, FTIR spectroscopy and XRD.
    Matched MeSH terms: Polymers
  17. Targeted delivery of paclitaxel drug using polymer-coated magnetic nanoparticles for fibrosarcoma therapy: in vitro and in vivo studies
    Al-Obaidy R, Haider AJ, Al-Musawi S, Arsad N
    Sci Rep, 2023 Feb 23;13(1):3180.
    PMID: 36823237 DOI: 10.1038/s41598-023-30221-x
    Fibrosarcoma is a rare type of cancer that affects cells known as fibroblasts that are malignant, locally recurring, and spreading tumor in fibrous tissue. In this work, an iron plate immersed in an aqueous solution of double added deionized water, supplemented with potassium permanganate solution (KMnO4) was carried out by the pulsed laser ablation in liquid method (PLAIL). Superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized using different laser wavelengths (1064, 532, and 266 nm) at a fluence of 28 J/cm2 with 100 shots of the iron plate to control the concentration, shape and size of the prepared high-stability SPIONs. The drug nanocarrier was synthesized by coating SPION with paclitaxel (PTX)-loaded chitosan (Cs) and polyethylene glycol (PEG). This nanosystem was functionalized by receptors that target folate (FA). The physiochemical characteristics of SPION@Cs-PTX-PEG-FA nanoparticles were evaluated and confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-Ray diffraction (XRD), atomic force microscopy (AFM), and dynamic light scattering (DLS) methods. Cell internalization, cytotoxicity assay (MTT), apoptosis induction, and gene expression of SPION@Cs-PTX-PEG-FA were estimated in fibrosarcoma cell lines, respectively. In vivo studies used BALB/c tumor-bearing mice. The results showed that SPION@Cs-PTX-PEG-FA exhibited suitable physical stability, spherical shape, desirable size, and charge. SPION@Cs-PTX-PEG-FA inhibited proliferation and induced apoptosis of cancer cells (P 
    Matched MeSH terms: Polymers
  18. Titanium-based nanocomposite materials: a review of recent advances and perspectives
    Shahadat M, Teng TT, Rafatullah M, Arshad M
    Colloids Surf B Biointerfaces, 2015 Feb 1;126:121-37.
    PMID: 25543989 DOI: 10.1016/j.colsurfb.2014.11.049
    This article explains recent advances in the synthesis and characterization of novel titanium-based nanocomposite materials. Currently, it is a pressing concern to develop innovative skills for the fabrication of hybrid nanomaterials under varying experimental conditions. This review generally focuses on the adsorption behavior of nanocomposites for the exclusion of organic and inorganic pollutants from industrial effluents and their significant applications in various fields. The assessment of recently published articles on the conjugation of organic polymers with titanium has revealed that these materials may be a new means of managing aquatic pollution. These nanocomposite materials not only create alternative methods for designing novel materials, but also develop innovative industrial applications. In the future, titanium-based hybrid nanomaterials are expected to open new approaches for demonstrating their outstanding applications in diverse fields.
    Matched MeSH terms: Polymers/chemistry*
  19. Carbohydrate polymers-based surface modified nano delivery systems for enhanced target delivery to colon cancer - A review
    Ibrahim IAA, Alzahrani AR, Alanazi IM, Shahzad N, Shahid I, Falemban AH, et al.
    Int J Biol Macromol, 2023 Dec 31;253(Pt 2):126581.
    PMID: 37652322 DOI: 10.1016/j.ijbiomac.2023.126581
    Carbohydrate polymers-based surface-modified nano-delivery systems have gained significant attention in recent years for enhancing targeted delivery to colon cancer. These systems leverage carbohydrate polymers' unique properties, such as biocompatibility, biodegradability, and controlled release. These properties make them suitable candidates for drug delivery applications. Nano-delivery systems loaded with bioactive compounds are well-studied for targeted colorectal cancer delivery. However, those drugs' target reach is still limited in various nano-delivery systems. To overcome this limitation, surface modification of nanoparticles with carbohydrate polymers like chitosan, pectin, alginate, and guar gum showed enhanced target-reaching capacity along with enhanced anticancer efficacy. Recently, a chitosan-decorated PLGA nanoparticle was constructed with tannic acid and vitamin E and showed long-term release of specific targets along with higher anticancer efficacy. Similarly, Chitosan-conjugated glucuronic acid-coated silica nanoparticles loaded with capecitabine were studied against colon cancer and found to be the pH-responsive controlled release of capecitabine with higher anticancer efficacy. Surface-modified carbohydrate polymers have promising potential for improving colon cancer target delivery. By leveraging the unique properties of these polymers, such as surface modification, pH responsiveness, mucoadhesion, controlled drug release, and combination therapy, researchers are working toward developing more effective and targeted treatment strategies for colon cancer.
    Matched MeSH terms: Polymers/chemistry
  20. Optimization and modelling of enzymatic polymerization of ε-caprolactone to polycaprolactone using Candida Antartica Lipase B with response surface methodology and artificial neural network
    Pakalapati H, Tariq MA, Arumugasamy SK
    Enzyme Microb Technol, 2019 Mar;122:7-18.
    PMID: 30638510 DOI: 10.1016/j.enzmictec.2018.12.001
    Recently enzymatic catalysts have replaced organic and organometallic catalysts in the synthesis of bio-resorbable polymers. Enzymatic polymerization is considered as an alternative to conventional polymerization as they are less toxic, environmental friendly and can operate under mild conditions. In this research, the enzymatic ring-opening polymerization (e-ROP) of e-caprolactone (e-CL) using Candida Antartica Lipase B (CALB) as catalyst to produce the Polycaprolactone. Two modelling techniques namely response surface methodology (RSM) and artificial neural network (ANN) have been used in this work. RSM is used to optimize the parameters and to develop a model of the process. ANN is used to develop the model to predict the results obtained from the experiment. The parameters involved are time, reaction temperature, mixing speed and enzyme-solvent ratio. The experimental result is Polydispersity index (PDI) of the polymer. The experimental data obtained was adequately fitted into second-order polynomial models. Simulation was done using artificial neural network model developed with Mean absolute error (MAD) value of 1.65 in comparison with MAD value of 7.4 for RSM. The Regression value (R2) values of RSM and ANN were found to be 0.96 and 0.93 respectively. The predictive models were validated experimentally and were found to be in agreement with the experimental values.
    Matched MeSH terms: Polymers
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