Displaying publications 1 - 20 of 36 in total

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  1. Zainuddin SY, Ahmad I, Kargarzadeh H, Abdullah I, Dufresne A
    Carbohydr Polym, 2013 Feb 15;92(2):2299-305.
    PMID: 23399291 DOI: 10.1016/j.carbpol.2012.11.106
    Biodegradable materials made from cassava starch and kenaf fibers were prepared using a solution casting method. Kenaf fibers were treated with NaOH, bleached with sodium chlorite and acetic buffer solution, and subsequently acid hydrolyzed to obtain cellulose nanocrystals (CNCs). Biocomposites in the form of films were prepared by mixing starch and glycerol/sorbitol with various filler compositions (0-10 wt%). X-ray diffraction revealed that fiber crystallinity increased after each stage of treatment. Morphological observations and size reductions of the extracted cellulose and CNCs were studied using field emission scanning electron microscopy and transmission electron microscopy. The effects of different treatments and filler contents of the biocomposites were evaluated through mechanical tests. Results showed that the tensile strengths and moduli of the biocomposites increased after each treatment and the optimum filler content was 6%.
  2. Tehami M, Imam HT, Abdullah I, Hosford J, Wong XJ, Rahman NA, et al.
    ACS Sustain Chem Eng, 2024 Feb 19;12(7):2678-2685.
    PMID: 38389905 DOI: 10.1021/acssuschemeng.3c06758
    1,4-Benzoxazines are important motifs in many pharmaceuticals and can be formed by a reaction sequence involving the oxidation of o-aminophenols to their corresponding quinone imine followed by an in situ inverse electron demand Diels-Alder (IEDDA) cycloaddition with a suitable dienophile. Reported herein is the development of a reaction sequence that employs horseradish peroxidase to catalyze the oxidation of the aminophenols prior to the IEDDA as a more sustainable alternative to the use of conventional stoichiometric oxidants. The synthesis of 10 example benzoxazines is demonstrated in this "one-pot, two-step" procedure with yields between 42% and 92%. The green chemistry metrics, including the E-factor and generalized reaction mass efficiency, for this biocatalytic reaction were compared against the conventional chemical approach. It was found that the reported biocatalytic route was approximately twice as green by these measures.
  3. Takhi M, Sreenivas K, Reddy CK, Munikumar M, Praveena K, Sudheer P, et al.
    Eur J Med Chem, 2014 Sep 12;84:382-94.
    PMID: 25036796 DOI: 10.1016/j.ejmech.2014.07.036
    A novel and potent series of ene-amides featuring azetidines has been developed as FabI inhibitors active against drug resistant Gram-positive pathogens particularly staphylococcal organisms. Most of the compounds from the series possessed excellent biochemical inhibition of Staphylococcus aureus FabI enzyme and whole cell activity against clinically relevant MRSA, MSSA and MRSE organisms which are responsible for significant morbidity and mortality in community as well as hospital settings. The binding mode of one of the leads, AEA16, in Escherichia coli FabI enzyme was determined unambiguously using X-ray crystallography. The lead compounds displayed good metabolic stability in mice liver microsomes and pharmacokinetic profile in mice. The in vivo efficacy of lead AEA16 has been demonstrated in a lethal murine systemic infection model.
  4. Shehab M, Alali A, Al-Hindawi A, Alsayegh A, Aldallal U, Abdullah I, et al.
    Front Med (Lausanne), 2022;9:1045661.
    PMID: 36687448 DOI: 10.3389/fmed.2022.1045661
    BACKGROUND: The impact of biologic therapies on body mass index (BMI) in patients with inflammatory bowel disease (IBD) is unclear. This study investigates any associations between BMI, type of IBD, and the type of medications taken among patients with IBD with varying weight categories.

    METHODS: A cross sectional study was performed in an IBD tertiary care center. Data was obtained from patients with IBD attending outpatient clinics from January 1st, 2021 until November 1st, 2021. Adult patients, older than 18 years, with a diagnosis of Crohn's disease (CD) or ulcerative colitis (UC) were recruited. The primary outcome was the association between BMI and medication used in IBD. The secondary outcome was the association between BMI and disease type and location in patients with IBD.

    RESULTS: The study included a total of 528 patients of which, 66.5% have CD. Patients with normal weight comprises 55.9% of the participants, while those who are underweight, overweight or obese are 3.4, 28.2, and 12.5%, respectively. None of the underweight patients had UC. Among the normal weight, overweight and obese BMI categories, 34.6% vs. 36.2% vs. 31.8% had UC, respectively. Patients who are on tumor necrosis factor inhibitors (anti-TNF) with an immunomodulator (anti-TNF combination), are more likely to be overweight or obese than patients who are not on anti-TNF combination (OR 2.86, 95% CI 1.739-4.711, p < 0.001). Patients on vedolizumab are twice as likely to be overweight or obese than patients not on vedolizumab (OR 2.23, 95% CI 1.086-4.584, p < 0.05). Patients with ileocolonic CD are more likely to be overweight or obese compared to other subtypes of CD (OR 1.78, 95% CI 1.14-2.77, p = 0.01).

    CONCLUSION: Many patients with IBD are either obese or overweight. Patients with IBD who are on anti-TNF combination therapy or vedolizumab monotherapy are more likely to be obese and overweight. In addition, patients will ileocolonic CD are more likely to be obese or overweight.

  5. Shehab M, Alrashed F, Abdullah I, Alfadhli A, Ali H, Abu-Farha M, et al.
    Front Med (Lausanne), 2022;9:881027.
    PMID: 35755075 DOI: 10.3389/fmed.2022.881027
    INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination has been effective in protecting against severe COVID-19 infections and related mortality. It is recommended for all individuals including patients with inflammatory bowel disease (IBD). However, safety data are lacking in this group of patients. Therefore, we aim to evaluate the short- and long-term vaccine related adverse events (AEs) in patients with IBD.

    METHODS: This is a prospective, observational cohort study investigating short- and long-term AEs related to the BNT162b2 vaccine in patients with IBD (study group) after the first and second dose compared to healthy participants (control group). Patients were recruited at the time of attendance to the clinic or infusion rooms. Short term (<3 weeks) localized and systemic AEs were assessed via questionnaire. Follow-up phone-based survey was made to collect data on long term (up to 24 weeks) AEs.

    RESULTS: A total of 408 patients answered the questionnaires, 204 patients in each group, the study and control group. No serious adverse events were reported in either the study or the control group after the first or the second dose. Participants in the control group reported more frequent pain at the injection site than those in the study group after the first dose [58 (57%) vs. 38 (37%) respectively, P = 0.005]. After the second dose, tiredness was reported more frequently in the control group [49 (48%)] compared to the study group [25 (24%) (P < 0.001)]. At 20-24 weeks post vaccination, 386 out of 408 (94.6%) patients were willing to participate in the follow-up phone based questionnaire [196 (96.1%) in the study group vs. 190 (93.1%) in the control group]. In both groups, none of the patients reported local, systemic, or severe adverse events (0 out of 386) at week 20-24 post second dose.

    CONCLUSION: The BNT162b2 vaccine is safe in patients with IBD. No severe or long-term adverse events were reported in our study. The frequency of local and systemic adverse events after the second dose was generally higher among healthy participants compared to patients with IBD. Further studies including a larger cohort with a longer follow-up duration are needed to assess for possible rare adverse events.

  6. Saleem F, Mehmood R, Mehar S, Khan MTJ, Khan ZU, Ashraf M, et al.
    Antioxidants (Basel), 2019 Jul 19;8(7).
    PMID: 31331076 DOI: 10.3390/antiox8070231
    Members of genus Pteris have their established role in the traditional herbal medicine system. In the pursuit to identify its biologically active constituents, the specie Pteris cretica L. (P. cretica) was selected for the bioassay-guided isolation. Two new maleates (F9 and CB18) were identified from the chloroform extract and the structures of the isolates were elucidated through their spectroscopic data. The putative targets, that potentially interact with both of these isolates, were identified through reverse docking by using in silico tools PharmMapper and ReverseScreen3D. On the basis of reverse docking results, both isolates were screened for their antioxidant, acetylcholinesterase (AChE) inhibition, α-glucosidase (GluE) inhibition and antibacterial activities. Both isolates depicted moderate potential for the selected activities. Furthermore, docking studies of both isolates were also studied to investigate the binding mode with respective targets followed by molecular dynamics simulations and binding free energies. Thereby, the current study embodies the poly-pharmacological potential of P. cretica.
  7. Rosli NA, Ahmad I, Abdullah I, Anuar FH, Mohamed F
    Carbohydr Polym, 2015 Jul 10;125:69-75.
    PMID: 25857961 DOI: 10.1016/j.carbpol.2015.03.002
    Graft copolymerisation of methyl methacrylate (MMA) onto Agave angustifolia was conducted with ceric ammonium nitrate (CAN) as the redox initiator. The maximum grafting efficiency was observed at CAN and MMA concentrations of 0.91 × 10(-3) and 5.63 × 10(-2)M, respectively, at 45°C for 3h reaction time. Four characteristic peaks at 2995, 1738, 1440, and 845 cm(-1), attributed to PMMA, were found in the IR spectrum of grafted cellulose. The crystallinity index dropped from 0.74 to 0.46, while the thermal stability improved upon grafting. The water contact angle increased with grafting yield, indicating increased hydrophobicity of cellulose. SEM images showed the grafted cellulose to be enlarged and rougher. The changes in the physical nature of PMMA-grafted cellulose can be attributed to the PMMA grafting in the amorphous regions of cellulose, causing it to expand at the expense of the crystalline component.
  8. Rosli NA, Ahmad I, Anuar FH, Abdullah I
    Carbohydr Polym, 2019 Jun 01;213:50-58.
    PMID: 30879689 DOI: 10.1016/j.carbpol.2019.02.074
    In this study, modified agave cellulose fibre combined by graft copolymerisation with methylmethacrylate was tested as a potential reinforcement for polylactic acid (PLA)-natural rubber/liquid natural rubber blends. Mechanical, morphological, thermal, wetting, and biodegradation characterisations were performed to assess the influence of cellulose-graft-polymethylmethacrylate (cell-g-PMMA) content on the properties of biocomposites. The addition of cell-g-PMMA improved the mechanical properties of the composites because of the chemical interaction between PLA and PMMA. Thermal stability decreased slightly upon cell-g-PMMA addition because of the low thermal stability of PMMA. A soil burial test revealed that the degradation of composites decreased with an increase in the cell-g-PMMA content. However, the weight loss after burial, which directly affected the water absorption capacity, was still higher for the cell-g-PMMA composites than for the polymer alone.
  9. Navookarasu NT, Rahman AR, Abdullah I
    Int J Clin Pract, 1999 Jan-Feb;53(1):25-30.
    PMID: 10344062
    Despite their proven value in reducing morbidity and mortality in different grades of heart failure, angiotensin converting enzyme (ACE) inhibitors continue to be underused. One reason for this is clinicians' apprehension of first-dose hypotension. We conducted a double-blind, randomised, placebo-controlled parallel group study to investigate the effect of various ACE inhibitors on first-dose hypotension. Eighty unselected patients were randomised into five treatment groups: placebo, captopril 6.25 mg, enalapril 2.5 mg, perindopril 2 mg and lisinopril 2.5 mg. Blood pressure was measured at baseline, half hourly for two hours and hourly for three hours after drug treatment. The maximum drops in mean arterial pressure (in mmHg +/- SD) were placebo 5.89 +/- 2.65, perindopril 5.29 +/- 2.49, enalapril 13.28 +/- 3.31, lisinopril 15.04 +/- 5.74 and captopril 16.76 +/- 5.74 (all p < 0.05 vs placebo except for perindopril). Perindopril, unlike the other ACE inhibitors studied, did not produce first-dose hypotension following its initiation in patients with congestive heart failure.
  10. Naheed N, Maher S, Saleem F, Khan A, Wadood A, Rasheed S, et al.
    Drug Dev Res, 2021 12;82(8):1169-1181.
    PMID: 33983647 DOI: 10.1002/ddr.21831
    Urease plays a significant role in the pathogenesis of urolithiasis pyelonephritis, urinary catheter encrustation, hepatic coma, hepatic encephalopathy, and peptic acid duodenal ulcers. Salvinia molesta was explored to identify new bioactive compounds with particular emphasis on urease inhibitors. The aqueous methanol extract was fractionated using solvents of increasing polarity. A series of column chromatography and later HPLC were performed on butanol extract. The structures of the resulting pure compounds were resolved using NMR (1D and 2D), infrared, and mass spectroscopy. The novel isolate was evaluated for antioxidant activity (using DPPH, superoxide anion radical scavenging, oxidative burst, and Fe+2 chelation assays), anti-glycation behavior, anticancer activity, carbonic anhydrase inhibition, phosphodiesterase inhibition, and urease inhibition. One new glucopyranose derivative 6'-O-(3,4-dihydroxybenzoyl)-4'-O-(4-hydroxybenzoyl)-α/β-D-glucopyranoside (1) and four known glycosides were identified. Glycoside 1 demonstrated promising antioxidant potential with IC50 values of 48.2 ± 0.3, 60.3 ± 0.6, and 42.1 ± 1.8 μM against DPPH, superoxide radical, and oxidative burst, respectively. Its IC50 in the Jack bean urease inhibition assay was 99.1 ± 0.8 μM. The mechanism-based kinetic studies presented that compound 1 is a mixed-type inhibitor of urease with a Ki value of 91.8 ± 0.1 μM. Finally, molecular dynamic simulations exploring the binding mode of compound 1 with urease provided quantitative agreement between estimated binding free energies and the experimental results. The studies corroborate the use of compound 1 as a lead for QSAR studies as an antioxidant and urease inhibitor. Moreover, it needs to be further evaluated through the animal model, that is, in vivo or tissue culture-based ex-vivo studies, to establish their therapeutic potential against oxidative stress phosphodiesterase-II and urease-induced pathologies.
  11. Mirza MU, Saadabadi A, Vanmeert M, Salo-Ahen OMH, Abdullah I, Claes S, et al.
    Eur J Pharm Sci, 2020 Dec 01;155:105537.
    PMID: 32890663 DOI: 10.1016/j.ejps.2020.105537
    Chemokine receptors are key regulators of cell migration in terms of immunity and inflammation. Among these, CCR5 and CXCR4 play pivotal roles in cancer metastasis and HIV-1 transmission and infection. They act as essential co-receptors for HIV and furnish a route to the cell entry. In particular, inhibition of either CCR5 or CXCR4 leads very often the virus to shift to a more virulent dual-tropic strain. Therefore, dual receptor inhibition might improve the therapeutic strategies against HIV. In this study, we aimed to discover selective CCR5, CXCR4, and dual CCR5/CXCR4 antagonists using both receptor- and ligand-based computational methods. We employed this approach to fully incorporate the interaction attributes of the binding pocket together with molecular dynamics (MD) simulations and binding free energy calculations. The best hits were evaluated for their anti-HIV-1 activity against CXCR4- and CCR5-specific NL4.3 and BaL strains. Moreover, the Ca2+ mobilization assay was used to evaluate their antagonistic activity. From the 27 tested compounds, three were identified as inhibitors: compounds 27 (CCR5), 6 (CXCR4) and 3 (dual) with IC50 values ranging from 10.64 to 64.56 μM. The binding mode analysis suggests that the active compounds form a salt bridge with the glutamates and π-stacking interactions with the aromatic side chains binding site residues of the respective co-receptor. The presented hierarchical virtual screening approach provides essential aspects in identifying potential antagonists in terms of selectivity against a specific co-receptor. The compounds having multiple heterocyclic nitrogen atoms proved to be relatively more specific towards CXCR4 inhibition as compared to CCR5. The identified compounds serve as a starting point for further development of HIV entry inhibitors through synthesis and quantitative structure-activity relationship studies.
  12. Mirza MU, Ahmad S, Abdullah I, Froeyen M
    Comput Biol Chem, 2020 Dec;89:107376.
    PMID: 32979815 DOI: 10.1016/j.compbiolchem.2020.107376
    Human ubiquitin carboxyl-terminal hydrolase-2 (USP2) inhibitors, such as thiopurine analogs, have been reported to inhibit SARS-CoV papain-like proteases (PLpro). The PLpro have significant functional implications in the innate immune response during SARS-CoV-2 infection and considered an important antiviral target. Both proteases share strikingly similar USP fold with right-handed thumb-palm-fingers structural scaffold and conserved catalytic triad Cys-His-Asp/Asn. In this urgency situation of COVID-19 outbreak, there is a lack of in-vitro facilities readily available to test SARS-CoV-2 inhibitors in whole-cell assays. Therefore, we adopted an alternate route to identify potential USP2 inhibitor through integrated in-silico efforts. After an extensive virtual screening protocol, the best compounds were selected and tested. The compound Z93 showed significant IC50 value against Jurkat (9.67 μM) and MOTL-4 cells (11.8 μM). The binding mode of Z93 was extensively analyzed through molecular docking, followed by MD simulations, and molecular interactions were compared with SARS-CoV-2. The relative binding poses of Z93 fitted well in the binding site of both proteases and showed consensus π-π stacking and H-bond interactions with histidine and aspartate/asparagine residues of the catalytic triad. These results led us to speculate that compound Z93 might be the first potential chemical lead against SARS-CoV-2 PLpro, which warrants in-vitro evaluations.
  13. Mekzali NW, Chee CW, Abdullah I, Lee YK, Rashid NN, Lee VS, et al.
    Med Chem, 2023;19(9):897-905.
    PMID: 37046198 DOI: 10.2174/1573406419666230410134213
    BACKGROUND: KRAS and p53 are two of the most common genetic alterations associated with colorectal cancer. New drug development targeting these mutated genes in colorectal cancer may serve as a potential treatment avenue to the current regimen.

    OBJECTIVE: The objective of the present study was to investigate the effects of alkoxy chain length and 1-hydroxy group on anticolorectal cancer activity of a series of 2-bromoalkoxyanthraquinones and corroborate it with their in silico properties.

    METHODS: In vitro anticancer activity of 2-bromoalkoxyanthraquinones was evaluated against HCT116, HT29, and CCD841 CoN cell lines, respectively. Molecular docking was performed to understand the interactions of these compounds with putative p53 and KRAS targets (7B4N and 6P0Z).

    RESULTS: 2-Bromoalkoxyanthraquinones with the 1-hydroxy group were proven to be more active than the corresponding counterparts in anticancer activity. Among the tested compounds, compound 6b with a C3 alkoxy chain exhibited the most promising antiproliferation activity against HCT116 cells (IC50 = 3.83 ± 0.05 μM) and showed high selectivity for HCT116 over CCD841 CoN cells (SI = 45.47). The molecular docking reveals additional hydrogen bonds between the 1-hydroxy group of 6b and the proteins. Compound 6b has adequate lipophilicity (cLogP = 3.27) and ligand efficiency metrics (LE = 0.34; LLE = 2.15) close to the proposed acceptable range for an initial hit.

    CONCLUSION: This work highlights the potential of the 1-hydroxy group and short alkoxy chain on anticolorectal cancer activity of 2-bromoalkoxyanthraquinones. Further optimisation may be warranted for compound 6b as a therapeutic agent against colorectal cancer.

  14. Manukaran MN, Ahmad H, Abdullah I
    Med J Malaysia, 1983 Mar;38(1):71-3.
    PMID: 6633343
    A case of amoebiasis with colonic perforation and ruptured liver abscess is reported. It is rare for both these complications to occur in the same patient. The management is described and the literature reviewed
  15. Li H, Khoury M, Bonef B, Alhassan AI, Mughal AJ, Azimah E, et al.
    ACS Appl Mater Interfaces, 2017 Oct 18;9(41):36417-36422.
    PMID: 28960058 DOI: 10.1021/acsami.7b11718
    We demonstrate efficient semipolar (11-22) 550 nm yellow/green InGaN light-emitting diodes (LEDs) with In0.03Ga0.97N barriers on low defect density (11-22) GaN/patterned sapphire templates. The In0.03Ga0.97N barriers were clearly identified, and no InGaN clusters were observed by atom probe tomography measurements. The semipolar (11-22) 550 nm InGaN LEDs (0.1 mm2 size) show an output power of 2.4 mW at 100 mA and a peak external quantum efficiency of 1.3% with a low efficiency drop. In addition, the LEDs exhibit a small blue-shift of only 11 nm as injection current increases from 5 to 100 mA. These results suggest the potential to produce high efficiency semipolar InGaN LEDs with long emission wavelength on large-area sapphire substrates with economical feasibility.
  16. Ilyas S, Tabasum R, Iftikhar A, Nazir M, Hussain A, Hussain A, et al.
    Sci Rep, 2021 01 18;11(1):1708.
    PMID: 33462261 DOI: 10.1038/s41598-020-80579-5
    Ifosfamide is a widely used chemotherapeutic agent having broad-spectrum efficacy against several tumors. However, nephro, hepato, neuro cardio, and hematological toxicities associated with ifosfamide render its use limited. These side effects could range from organ failure to life-threatening situations. The present study aimed to evaluate the attenuating efficiency of Berberis vulgaris root extract (BvRE), a potent nephroprotective, hepatoprotective, and lipid-lowering agent, against ifosfamide-induced toxicities. The study design comprised eight groups of Swiss albino rats to assess different dose regimes of BvRE and ifosfamide. Biochemical analysis of serum (serum albumin, blood urea nitrogen, creatinine, alanine transaminase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase, total cholesterol, and triglycerides) along with complete blood count was performed. Kidney, liver, brain, and heart tissue homogenates were used to find malondialdehyde, catalase, and glutathione S-transferase levels in addition to the acetylcholinesterase of brain tissue. The results were further validated with the help of the histopathology of the selected organs. HeLa cells were used to assess the effect of BvRE on ifosfamide cytotoxicity in MTT assay. The results revealed that pre- and post-treatment regimens of BvRE, as well as the combination therapy exhibited marked protective effects against ifosfamide-induced nephro, hepato, neuro, and cardiotoxicity. Moreover, ifosfamide depicted a synergistic in vitro cytotoxic effect on HeLa cells in the presence of BvRE. These results corroborate that the combination therapy of ifosfamide with BvRE in cancer treatment can potentiate the anticancer effects of ifosfamide along with the amelioration of its conspicuous side effects.
  17. Ilmiah WS, Abdullah I, Koesrini J
    J Public Health Afr, 2023 Dec 27;14(12):2349.
    PMID: 38204814 DOI: 10.4081/jphia.2023.2349
    One of the most common female reproductive health problems is primary dysmenorrhea. Data on the incidence of primary dysmenorrhea complained about 50-90% of women in the world. Primary dysmenorrhea data in the US is 30-70%, in Sweden is 30%, in Mexico is 64%, in Italy is 68%, in Jordan is 55.8%, in Turkey is 84.9%, and in Malaysia is 74.5%, in Indonesia is 60-70 and 15% of its, it interferes with daily activities including work. The cause of this is hypercontractility of the myometrium due to excessive secretion of prostaglandins. This study aims to explore the most effective non-pharmacological therapies in reducing the level of primary dysmenorrhea pain in women of childbearing age. The design of this study is a literature review with the PRISMA method. Database Google, Google Scholar, Research gate, Cochran Data Base, Embase, NCBI, Sciendirect, SAGE, Elsevier, Sinta. The population of this study was all full-text international journals indexed by Scopus and national journals indexed by Sinta 1-6 published in 2011-2021 including RCT amount of 114 articles. A sample of 23 articles meets the inclusion criteria and used thematic data analysis. The results of non-pharmacological therapy that effectively overcome primary dysmenorrhea pain, namely the first group with (P=0.000). The conclusions showed that Murrotal Qur'an, yoga, acupressure, counter pressure massage, effleurage massage, consume green coconut water and avocado juice combination with massage were proven to be equally effective in overcoming complaints of primary dysmenorrhea pain quickly without being accompanied by side effects.
  18. Hussain AI, Rathore HA, Sattar MZ, Chatha SA, Sarker SD, Gilani AH
    J Ethnopharmacol, 2014 Aug 8;155(1):54-66.
    PMID: 24936768 DOI: 10.1016/j.jep.2014.06.011
    Citrullus colocynthis (L.) Schrad is a valuable cucurbit plant, widely distributed in the desert areas of the world. Citrullus colocynthis fruits are usually recognized for its wide range of medicinal uses as well as pharmaceutical and nutraceutical potential. This review aims to appraise the published information on the ethnobotanical knowledge, phytochemistry, ethnopharmacology, nutraceutical potential and safety studies of Citrullus colocynthis (bitter apple) fruit, with critical analysis on the gaps and potential for future studies.
  19. Ghalib, H., Abdullah, I., Daik, R.
    MyJurnal
    Conducting polypyrrole (PPy) nanoparticles were synthesized by chemical oxidative polymerization of pyrrole in aqueous solution containing ferric sulfate (Fe2(SO4)3), anionic surfactants (sodium dodecylbenzene-sulfonate (NaDBS) or sodium dodecyl sulfate (SDS)), 1-pentanol as the oxidant, dopant and co-emulsifier, respectively. The polymerization was carried out at 0 ºC and 25 ºC. Fourier transform infrared spectroscopy (FTIR) and elemental analysis indicated that anionic surfactants were successfully incorporated into the PPy backbone. Incorporation of anionic surfactants caused enhanced electrical conductivity, increased yield, decreased the size of particles as well as improved the thermal stability of the resultant PPy. The presence of anionic surfactant seems to inhibit undesirable side reactions so as to improve the regularity of the PPy backbone. Globular PPy particles were obtained with diameter ranged from 40 to 118 nm as revealed by field emission scanning electron microscopy (FE-SEM) and conductivity of 7.89×10-4 –2.35×10-2 S cm-1, as measured using impedance analyzer. It was found that polymerization at low temperature (0 ºC) produced PPy particles with smaller size and higher conductivity. The sodium dodecyl sulfate-doped PPy (SDS-doped PPy) exhibited higher conductivity than that of the sodium dodecylbenzenesulfonate-doped PPy (NaDBS-doped PPy), due to the bulkiness of NaDBS as compared to SDS.
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