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Dr. Rohan Dassanayake
University of Sri Jayewardenepura

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0 Material Characterisation
0 Titanium dioxide
0 antimicrobial activity
0 cellulose nanocrystals
0 aerogels

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chitin
CO2 adsorption
Manganese dioxide
aerogels
Dye removal
cellulose aerogel

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Review
Published: 03 August 2021 in Molecules
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Synthetic dyes have become an integral part of many industries such as textiles, tannin and even food and pharmaceuticals. Industrial dye effluents from various dye utilizing industries are considered harmful to the environment and human health due to their intense color, toxicity and carcinogenic nature. To mitigate environmental and public health related issues, different techniques of dye remediation have been widely investigated. However, efficient and cost-effective methods of dye removal have not been fully established yet. This paper highlights and presents a review of recent literature on the utilization of the most widely available biopolymers, specifically, cellulose, chitin and chitosan-based products for dye removal. The focus has been limited to the three most widely explored technologies: adsorption, advanced oxidation processes and membrane filtration. Due to their high efficiency in dye removal coupled with environmental benignity, scalability, low cost and non-toxicity, biopolymer-based dye removal technologies have the potential to become sustainable alternatives for the remediation of industrial dye effluents as well as contaminated water bodies.

ACS Style

Rohan Dassanayake; Sanjit Acharya; Noureddine Abidi. Recent Advances in Biopolymer-Based Dye Removal Technologies. Molecules 2021, 26, 4697 .

AMA Style

Rohan Dassanayake, Sanjit Acharya, Noureddine Abidi. Recent Advances in Biopolymer-Based Dye Removal Technologies. Molecules. 2021; 26 (15):4697.

Chicago/Turabian Style

Rohan Dassanayake; Sanjit Acharya; Noureddine Abidi. 2021. "Recent Advances in Biopolymer-Based Dye Removal Technologies." Molecules 26, no. 15: 4697.

Journal article
Published: 03 February 2021 in Journal of Composites Science
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In this study, two types of modified cassava starch samples (MCS and MWS) prepared from commercially available native cassava starch (NCS) and native cassava starch extracted using the wet method (NWS) were investigated for the removal of Pb(II) ions from aqueous solutions. MCS and MWS samples were synthesized under acidic conditions using Pluronic 123 as the structure-directing agent and tetraethylorthosilicate (TEOS) as the chemical modifying agent. Modified starch samples were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray Diffraction (XRD), and a nitrogen (N2) gas adsorption–desorption analyser. MCS and MWS showed enhanced thermal stabilities upon acid hydrolysis and chemical modification. The effects of contact time and initial Pb(II) concentration were studied through batch adsorption experiments. Adsorption kinetics followed the pseudo-second-order kinetic model. The equilibrium adsorption data were analysed and compared by the Langmuir and Freundlich adsorption models. The coefficient correlation (R2) was employed as a measure of the fit. The Langmuir model fitted well with equilibrium adsorption data, giving a maximum Pb(II) adsorption capacity of 370.37 and 294.12 mg/g for MWS and MCS, respectively. Modified samples exhibited a higher desorption efficiency of over 97%. This study demonstrated that modified starch could be utilized for Pb(II) removal from industrial wastewater.

ACS Style

O. Gunawardene; C. Gunathilake; A. Amaraweera; N. Fernando; A. Manipura; W. Manamperi; K. Kulatunga; S. Rajapaksha; A. Gamage; R. Dassanayake; B. Weerasekara; P. Fernando; C. Fernando; J. Jayasinghe. Removal of Pb(II) Ions from Aqueous Solution Using Modified Starch. Journal of Composites Science 2021, 5, 46 .

AMA Style

O. Gunawardene, C. Gunathilake, A. Amaraweera, N. Fernando, A. Manipura, W. Manamperi, K. Kulatunga, S. Rajapaksha, A. Gamage, R. Dassanayake, B. Weerasekara, P. Fernando, C. Fernando, J. Jayasinghe. Removal of Pb(II) Ions from Aqueous Solution Using Modified Starch. Journal of Composites Science. 2021; 5 (2):46.

Chicago/Turabian Style

O. Gunawardene; C. Gunathilake; A. Amaraweera; N. Fernando; A. Manipura; W. Manamperi; K. Kulatunga; S. Rajapaksha; A. Gamage; R. Dassanayake; B. Weerasekara; P. Fernando; C. Fernando; J. Jayasinghe. 2021. "Removal of Pb(II) Ions from Aqueous Solution Using Modified Starch." Journal of Composites Science 5, no. 2: 46.

Journal article
Published: 20 May 2020 in Journal of Composites Science
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In this work, disc-like hematite (Fe2O3) nanoparticles were prepared using a readily available inexpensive earth material, ferruginous laterite, via a low-cost synthesis route. Prepared hematite nanoparticles were characterized using X-Ray diffraction (XRD), inductively coupled plasma mass spectroscopy (ICP-MS), particle size analyzer (PSA), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and nitrogen adsorption-desorption analyzer. The performance of hematite nanoparticles was evaluated as a heavy metal ion adsorbent. Batch adsorption experiments were conducted to study the adsorption behaviour of Ni2+ and Cd2+ ions as a function of the amount of adsorbent, contact time, and pH. Adsorption data fitted to the linearized Langmuir and Freundlich kinetic models were compared and discussed. The correlation coefficient (R2) was used to determine the best fit kinetic model. Our data fitted the Langmuir kinetic model well and the highest adsorption efficiencies were found to be 62.5 mg/g for Ni2+ and 200 mg/g for Cd2+, respectively. Due to high surface area, pore volume with active sites, and sorption capabilities, hematite nanoparticles can be used as efficient and economical nano-adsorbents for the removal of Ni2+ and Cd2+ ions from industrial wastewater.

ACS Style

B.P. Nishantha Gunawardhana; C. A. Gunathilake; Taniya Dayananda; D. M. S. N. Dissanayake; M. M. M. G. P. G. Mantilaka; C. S. Kalpage; R. M. L. D. Rathnayake; R. M. G. Rajapakse; A. S. Manchanda; Thusitha N. B. Etampawala; B. G. N. D. Weerasekara; P. N. K. Fernando; Rohan S. Dassanayake. Synthesis of Hematite Nanodiscs from Natural Laterites and Investigating Their Adsorption Capability of Removing Ni2+ and Cd2+ Ions from Aqueous Solutions. Journal of Composites Science 2020, 4, 57 .

AMA Style

B.P. Nishantha Gunawardhana, C. A. Gunathilake, Taniya Dayananda, D. M. S. N. Dissanayake, M. M. M. G. P. G. Mantilaka, C. S. Kalpage, R. M. L. D. Rathnayake, R. M. G. Rajapakse, A. S. Manchanda, Thusitha N. B. Etampawala, B. G. N. D. Weerasekara, P. N. K. Fernando, Rohan S. Dassanayake. Synthesis of Hematite Nanodiscs from Natural Laterites and Investigating Their Adsorption Capability of Removing Ni2+ and Cd2+ Ions from Aqueous Solutions. Journal of Composites Science. 2020; 4 (2):57.

Chicago/Turabian Style

B.P. Nishantha Gunawardhana; C. A. Gunathilake; Taniya Dayananda; D. M. S. N. Dissanayake; M. M. M. G. P. G. Mantilaka; C. S. Kalpage; R. M. L. D. Rathnayake; R. M. G. Rajapakse; A. S. Manchanda; Thusitha N. B. Etampawala; B. G. N. D. Weerasekara; P. N. K. Fernando; Rohan S. Dassanayake. 2020. "Synthesis of Hematite Nanodiscs from Natural Laterites and Investigating Their Adsorption Capability of Removing Ni2+ and Cd2+ Ions from Aqueous Solutions." Journal of Composites Science 4, no. 2: 57.

Paper
Published: 24 February 2020 in Environmental Science: Nano
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MONP and MONP–GO sorbents exhibited relatively high CO2 sorption capacity (2.79–3.34 mmol g−1) under elevated temperature conditions.

ACS Style

Chamila Gunathilake; G. G. T. A. Ranathunge; R. S. Dassanayake; S. D. Illesinghe; Amanpreet S. Manchanda; Chandrakantha Senajith Kalpage; R. M. G. Rajapakse; D. G. G. P. Karunaratne. Emerging investigator series: synthesis of magnesium oxide nanoparticles fabricated on a graphene oxide nanocomposite for CO2 sequestration at elevated temperatures. Environmental Science: Nano 2020, 7, 1225 -1239.

AMA Style

Chamila Gunathilake, G. G. T. A. Ranathunge, R. S. Dassanayake, S. D. Illesinghe, Amanpreet S. Manchanda, Chandrakantha Senajith Kalpage, R. M. G. Rajapakse, D. G. G. P. Karunaratne. Emerging investigator series: synthesis of magnesium oxide nanoparticles fabricated on a graphene oxide nanocomposite for CO2 sequestration at elevated temperatures. Environmental Science: Nano. 2020; 7 (4):1225-1239.

Chicago/Turabian Style

Chamila Gunathilake; G. G. T. A. Ranathunge; R. S. Dassanayake; S. D. Illesinghe; Amanpreet S. Manchanda; Chandrakantha Senajith Kalpage; R. M. G. Rajapakse; D. G. G. P. Karunaratne. 2020. "Emerging investigator series: synthesis of magnesium oxide nanoparticles fabricated on a graphene oxide nanocomposite for CO2 sequestration at elevated temperatures." Environmental Science: Nano 7, no. 4: 1225-1239.

Journal article
Published: 01 August 2019 in Journal of Composites Science
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Titania-incorporated organosilica-mesostructures (Ti-MO) were synthesized using tris [3-(trimethoxysilyl)propyl]isocyanurate, tetraethylorthosilicate as silica precursors, and titanium isopropoxide as the titanium precursor via a co-condensation method in the presence of the triblock copolymer, Pluronic P123. The triblock copolymer was completely removed by extraction with a 95% ethanol solution, followed by a thermal treatment at 350 °C under flowing nitrogen without decomposing isocyanurate bridging groups. The molar ratio of titanium to silica in the mesostructures was gradually changed by increasing the amount of tetraethylorthosilicate in the initial reaction mixture. Our synthesis strategy also allowed us to tailor both adsorption and structural properties, including a well-developed specific surface area, high microporosity, and large pore volume. A portion of the samples was thermally treated at 600 °C to remove both the block copolymer and bridging groups. The thermal treatment at 600 °C was used to convert the amorphous titania into a crystalline anatase form. The Ti-MO materials were characterized using a N2 adsorption desorption analysis, thermogravimetric analysis (TGA), solid state nuclear magnetic resonance (NMR), transmission electron microscope (TEM), and X-ray powder diffraction (XRD). CO2 adsorption studies were also conducted to determine the basicity of the Ti-MO materials. The effect of the surface properties on the CO2 sorption was also identified.

ACS Style

Chamila Gunathilake; Chandrakantha Kalpage; Murthi Kadanapitiye; Rohan S. Dassanayake; Amanpreet S. Manchanda; Mahinda Gangoda. Facile Synthesis and Surface Characterization of Titania-Incorporated Mesoporous Organosilica Materials. Journal of Composites Science 2019, 3, 77 .

AMA Style

Chamila Gunathilake, Chandrakantha Kalpage, Murthi Kadanapitiye, Rohan S. Dassanayake, Amanpreet S. Manchanda, Mahinda Gangoda. Facile Synthesis and Surface Characterization of Titania-Incorporated Mesoporous Organosilica Materials. Journal of Composites Science. 2019; 3 (3):77.

Chicago/Turabian Style

Chamila Gunathilake; Chandrakantha Kalpage; Murthi Kadanapitiye; Rohan S. Dassanayake; Amanpreet S. Manchanda; Mahinda Gangoda. 2019. "Facile Synthesis and Surface Characterization of Titania-Incorporated Mesoporous Organosilica Materials." Journal of Composites Science 3, no. 3: 77.

Journal article
Published: 19 June 2019 in Fibers
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A cellulose-cadmium (Cd)-tellurium (TE) quantum dots (QDs) composite film was successfully synthesized by incorporating CdTe QDs onto a cellulose matrix derived from waste cotton linters. Cellulose-CdTe QDs composite film was characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The antibacterial activity of the prepared composite film was investigated using the multidrug-resistance (MTR) Staphylococcus aureus bacteria. In vitro antibacterial assays demonstrated that CdTe QDs composite film can efficiently inhibit biofilm formation. Our results showed that the cellulose-CdTe QDs composite film is a promising candidate for biomedical applications including wound dressing, medical instruments, burn treatments, implants, and other biotechnology fields.

ACS Style

Rohan S. Dassanayake; Poorna T. Wansapura; Phat Tran; Abdul Hamood; Noureddine Abidi. Cotton Cellulose-CdTe Quantum Dots Composite Films with Inhibition of Biofilm-Forming S. aureus. Fibers 2019, 7, 57 .

AMA Style

Rohan S. Dassanayake, Poorna T. Wansapura, Phat Tran, Abdul Hamood, Noureddine Abidi. Cotton Cellulose-CdTe Quantum Dots Composite Films with Inhibition of Biofilm-Forming S. aureus. Fibers. 2019; 7 (6):57.

Chicago/Turabian Style

Rohan S. Dassanayake; Poorna T. Wansapura; Phat Tran; Abdul Hamood; Noureddine Abidi. 2019. "Cotton Cellulose-CdTe Quantum Dots Composite Films with Inhibition of Biofilm-Forming S. aureus." Fibers 7, no. 6: 57.

Research article
Published: 31 January 2019 in Journal of Nanomaterials
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Borax-cross-linked guar gum-manganese dioxide (GGB-MnO2) composite was synthesized using an environmentally friendly synthesis route and investigated for its efficiency of decolorizing methylene blue (MB) dye solution by an ultraviolet-visible (UV-Vis) spectrophotometric study. The GGB-MnO2 composite was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). The composite (1.2 g/L) exhibited excellent oxidative decolorization of MB (30 mg/L, 50 mL) solution to over 99% in 6, 13, and 40 min at pH 4, 7, and 10, respectively. The complete decolorization of MB occurred via a catalytic adsorption-oxidation-desorption mechanism. The GGB-MnO2 composite showed very good reusability and was stable after ten successive cycles with negligible losses of the decolorization efficiency.

ACS Style

Rohan Dassanayake; Erandathi Rajakaruna; Noureddine Abidi. Borax-Cross-Linked Guar Gum-Manganese Dioxide Composites for Oxidative Decolorization of Methylene Blue. Journal of Nanomaterials 2019, 2019, 1 -11.

AMA Style

Rohan Dassanayake, Erandathi Rajakaruna, Noureddine Abidi. Borax-Cross-Linked Guar Gum-Manganese Dioxide Composites for Oxidative Decolorization of Methylene Blue. Journal of Nanomaterials. 2019; 2019 ():1-11.

Chicago/Turabian Style

Rohan Dassanayake; Erandathi Rajakaruna; Noureddine Abidi. 2019. "Borax-Cross-Linked Guar Gum-Manganese Dioxide Composites for Oxidative Decolorization of Methylene Blue." Journal of Nanomaterials 2019, no. : 1-11.

Journal article
Published: 16 November 2018 in Materials
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Two series of alumina (Al2O3)–mesoporous organosilica (Al–MO) hybrid materials were synthesized using the co-condensation method in the presence of Pluronic 123 triblock copolymer. The first series of Al–MO samples was prepared using aluminum nitrate nanahydrate (Al–NN) and aluminum isopropoxide (Al–IP) as alumina precursors, and organosilanes with three different bridging groups, namely tris[3-(trimethoxysilyl)propyl]isocyanurate, 1,4-bis(triethoxysilyl)benzene, and bis(triethoxysilyl)ethane. The second series was obtained using the aforementioned precursors in the presence of an amine-containing 3-aminopropyltriethoxysilane to introduce, also, hanging groups. The Al–IP-derived mesostructures in the first series showed the well-developed porosity and high specific surface area, as compared to the corresponding mesostructures prepared in the second series with 3-aminopropyltriethoxysilane. The materials obtained from Al–NN alumina precursor possessed enlarged mesopores in the range of 3–17 nm, whereas the materials synthesized from Al–IP alumina precursor displayed relatively low pore widths in the range of 5–7 nm. The Al–IP-derived materials showed high CO2 uptakes, due to the enhanced surface area and microporosity in comparison to those observed for the samples of the second series with AP hanging groups. The Al–NN- and Al–IP-derived samples exhibited the CO2 uptakes in the range of 0.73–1.72 and 1.66–2.64 mmol/g at 1 atm pressure whereas, at the same pressure, the Al–NN and Al–IP-derived samples with 3-aminopropyl hanging groups showed the CO2 uptakes in the range of 0.72–1.51 and 1.70–2.33 mmol/g, respectively. These data illustrate that Al–MO hybrid materials are potential adsorbents for large-scale CO2 capture at 25 °C.

ACS Style

Chamila Gunathilake; Rohan S. Dassanayake; Chandrakantha S. Kalpage; Mietek Jaroniec. Development of Alumina–Mesoporous Organosilica Hybrid Materials for Carbon Dioxide Adsorption at 25 °C. Materials 2018, 11, 2301 .

AMA Style

Chamila Gunathilake, Rohan S. Dassanayake, Chandrakantha S. Kalpage, Mietek Jaroniec. Development of Alumina–Mesoporous Organosilica Hybrid Materials for Carbon Dioxide Adsorption at 25 °C. Materials. 2018; 11 (11):2301.

Chicago/Turabian Style

Chamila Gunathilake; Rohan S. Dassanayake; Chandrakantha S. Kalpage; Mietek Jaroniec. 2018. "Development of Alumina–Mesoporous Organosilica Hybrid Materials for Carbon Dioxide Adsorption at 25 °C." Materials 11, no. 11: 2301.

Original paper
Published: 18 January 2018 in Cellulose
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Activated carbon was prepared by carbonization and KOH activation of chitin aerogels. The resulting carbon featured high CO2 adsorption of 5.02 mmol/g at 0 °C and 3.44 mmol/g at 25 °C under ambient pressure of 1 atm. The activated carbon showed a high specific surface area of ~ 520 m2/g, total pore volume of 0.30 cm3/g, and volume of micropores of ~ 0.19 cm3/g. KOH activation of carbonized chitin aerogels resulted in about 37-fold increase in the specific surface area and about 95-fold increase in the volume of micropores as compared to the as-synthesized chitin aerogel. These data indicate that the chitin-derived activated carbon can be used for adsorption-based environmental and related applications.

ACS Style

Rohan Dassanayake; Chamila Gunathilake; Noureddine Abidi; Mietek Jaroniec. Activated carbon derived from chitin aerogels: preparation and CO2 adsorption. Cellulose 2018, 25, 1911 -1920.

AMA Style

Rohan Dassanayake, Chamila Gunathilake, Noureddine Abidi, Mietek Jaroniec. Activated carbon derived from chitin aerogels: preparation and CO2 adsorption. Cellulose. 2018; 25 (3):1911-1920.

Chicago/Turabian Style

Rohan Dassanayake; Chamila Gunathilake; Noureddine Abidi; Mietek Jaroniec. 2018. "Activated carbon derived from chitin aerogels: preparation and CO2 adsorption." Cellulose 25, no. 3: 1911-1920.

Article
Published: 30 October 2017 in Journal of Polymer Science
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An aerochitin–titania (TiO2) composite was successfully synthesized and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, field emission scanning electron microscopy, and N2 adsorption isotherms. The photocatalytic activity of the composite was investigated on the degradation of the model organic pollutant, methylene blue (MB) dye, under UV irradiation. The aerochitin–TiO2 composite showed excellent adsorptive and photocatalytic activity with a degradation degree of 98% for MB. The first-order rate constants for the photodegradation MB by TiO2 nanoparticles and aerochitin–TiO2 composite were found to be (3.49 ± 0.04) × 10−3 and (1.82 ± 0.02) × 10−2 min−1. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45908.

ACS Style

Rohan Dassanayake; Erandathi Rajakaruna; Noureddine Abidi. Preparation of aerochitin-TiO2 composite for efficient photocatalytic degradation of methylene blue. Journal of Polymer Science 2017, 135, 1 .

AMA Style

Rohan Dassanayake, Erandathi Rajakaruna, Noureddine Abidi. Preparation of aerochitin-TiO2 composite for efficient photocatalytic degradation of methylene blue. Journal of Polymer Science. 2017; 135 (8):1.

Chicago/Turabian Style

Rohan Dassanayake; Erandathi Rajakaruna; Noureddine Abidi. 2017. "Preparation of aerochitin-TiO2 composite for efficient photocatalytic degradation of methylene blue." Journal of Polymer Science 135, no. 8: 1.

Journal article
Published: 01 October 2017 in Journal of Molecular Structure
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ACS Style

M. Messali; H. Lgaz; R. Dassanayake; R. Salghi; S. Jodeh; N. Abidi; O. Hamed. Guar gum as efficient non-toxic inhibitor of carbon steel corrosion in phosphoric acid medium: Electrochemical, surface, DFT and MD simulations studies. Journal of Molecular Structure 2017, 1145, 43 -54.

AMA Style

M. Messali, H. Lgaz, R. Dassanayake, R. Salghi, S. Jodeh, N. Abidi, O. Hamed. Guar gum as efficient non-toxic inhibitor of carbon steel corrosion in phosphoric acid medium: Electrochemical, surface, DFT and MD simulations studies. Journal of Molecular Structure. 2017; 1145 ():43-54.

Chicago/Turabian Style

M. Messali; H. Lgaz; R. Dassanayake; R. Salghi; S. Jodeh; N. Abidi; O. Hamed. 2017. "Guar gum as efficient non-toxic inhibitor of carbon steel corrosion in phosphoric acid medium: Electrochemical, surface, DFT and MD simulations studies." Journal of Molecular Structure 1145, no. : 43-54.

Journal article
Published: 25 March 2017 in Journal of Materials Chemistry A
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Nanocrystalline cellulose–mesoporous silica composites with attached double amidoxime groups show high CO2sorption at elevated temperatures.

ACS Style

Rohan Dassanayake; Chamila Gunathilake; Arosha C. Dassanayake; Noureddine Abidi; Mietek Jaroniec. Amidoxime-functionalized nanocrystalline cellulose–mesoporous silica composites for carbon dioxide sorption at ambient and elevated temperatures. Journal of Materials Chemistry A 2017, 5, 7462 -7473.

AMA Style

Rohan Dassanayake, Chamila Gunathilake, Arosha C. Dassanayake, Noureddine Abidi, Mietek Jaroniec. Amidoxime-functionalized nanocrystalline cellulose–mesoporous silica composites for carbon dioxide sorption at ambient and elevated temperatures. Journal of Materials Chemistry A. 2017; 5 (16):7462-7473.

Chicago/Turabian Style

Rohan Dassanayake; Chamila Gunathilake; Arosha C. Dassanayake; Noureddine Abidi; Mietek Jaroniec. 2017. "Amidoxime-functionalized nanocrystalline cellulose–mesoporous silica composites for carbon dioxide sorption at ambient and elevated temperatures." Journal of Materials Chemistry A 5, no. 16: 7462-7473.

Article
Published: 07 February 2017 in Journal of Applied Polymer Science
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Novel chitin–cadmium-tellurium quantum dot (Chitin-CdTeQD) hybrid films combining chitin and CdTe quantum dots (CdTeQDs) were prepared via a facile aqueous synthesis route at room temperature. Films were characterized by high-resolution field emission scanning electron microscopy (HR-FESEM) and energy dispersive X-ray (EDX) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and X-ray diffraction analysis (XRD). Antibacterial activity was studied on both Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria. Antibacterial properties were investigated with agar diffusion testing assay and with confocal laser scanning microscopic image analysis. Chitin–CdTeQD films exhibited an excellent antibacterial activity against both Gram-positive and Gram-negative bacteria. Chitin–CdTeQD films might be a desirable antibacterial material for wide range of biomedical applications including wound dressing, burn treatment, drug delivery systems, packaging, ophthalmology, and implants. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44904.

ACS Style

Poorna Tharaka Wansapura; Rohan Dassanayake; Abdul Hamood; Phat Tran; Hanna Moussa; Noureddine Abidi. Preparation of chitin-CdTe quantum dots films and antibacterial effect onStaphylococcus aureusandPseudomonas aeruginosa. Journal of Applied Polymer Science 2017, 134, 1 .

AMA Style

Poorna Tharaka Wansapura, Rohan Dassanayake, Abdul Hamood, Phat Tran, Hanna Moussa, Noureddine Abidi. Preparation of chitin-CdTe quantum dots films and antibacterial effect onStaphylococcus aureusandPseudomonas aeruginosa. Journal of Applied Polymer Science. 2017; 134 (22):1.

Chicago/Turabian Style

Poorna Tharaka Wansapura; Rohan Dassanayake; Abdul Hamood; Phat Tran; Hanna Moussa; Noureddine Abidi. 2017. "Preparation of chitin-CdTe quantum dots films and antibacterial effect onStaphylococcus aureusandPseudomonas aeruginosa." Journal of Applied Polymer Science 134, no. 22: 1.

Micro article
Published: 02 February 2017 in MethodsX
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In Fourier transform infrared (FTIR) microspectrocopy, the tissue preparation method is crucial, especially how the tissue is cryo-sectioned prior to the imaging requires special consideration. Having a temperature difference between the cutting blade and the specimen holder of the cryostat greatly affects the quality of the sections. Therefore, we have developed an optimal protocol for cryo-sectioning of biological tissues by varying the temperature of both the cutting blade and the specimen holder. Using this protocol, we successfully cryo-sectioned four different difficult-to-section tissues including white adipose tissue (WAT), brown adipose tissue (BAT), lung, and liver. The optimal temperatures that required to be maintained at the cutting blade and the specimen holder for the cryo-sectioning of WAT, BAT, lung, and liver are (−25, −20 °C), (−25, −20 °C), (−17, −13 °C) and (−15, −5 °C), respectively. The optimized protocol developed in this study produced high quality cryo-sections with sample thickness of 8–10 μm, as well as high quality trans-reflectance mode FTIR microspectroscopic images for the tissue sections.

ACS Style

Sumedha Liyanage; Rohan S. Dassanayake; Amal Bouyanfif; Erandathi Rajakaruna; Latha Ramalingam; Naima Moustaid-Moussa; Noureddine Abidi. Optimization and validation of cryostat temperature conditions for trans-reflectance mode FTIR microspectroscopic imaging of biological tissues. MethodsX 2017, 4, 118 -127.

AMA Style

Sumedha Liyanage, Rohan S. Dassanayake, Amal Bouyanfif, Erandathi Rajakaruna, Latha Ramalingam, Naima Moustaid-Moussa, Noureddine Abidi. Optimization and validation of cryostat temperature conditions for trans-reflectance mode FTIR microspectroscopic imaging of biological tissues. MethodsX. 2017; 4 ():118-127.

Chicago/Turabian Style

Sumedha Liyanage; Rohan S. Dassanayake; Amal Bouyanfif; Erandathi Rajakaruna; Latha Ramalingam; Naima Moustaid-Moussa; Noureddine Abidi. 2017. "Optimization and validation of cryostat temperature conditions for trans-reflectance mode FTIR microspectroscopic imaging of biological tissues." MethodsX 4, no. : 118-127.

Journal article
Published: 01 December 2016 in International Journal of Biological Macromolecules
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Manganese dioxide (MnO)-chitin-hybrid material was prepared by a facile "one-pot" synthesis method. MnO-chitin hybrid was used for the effective removal of methylene blue (MB) from liquid solution as model for wastewater treatment. The hybrid obtained was characterized by field emission scanning electron microscopy and energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. The effect of pH and temperature were studied. MnO-chitin hybrid showed high performance for oxidative decolorization and removal of MB. Typically, 25mL of MB (20mg/L) can be completely decolorized in 2.5min with 8.5mg of the MnO-chitin hybrid. The hybrid material exhibited excellent recyclability and durability with the degradation value of 99% for MB after ten consecutive cycles.

ACS Style

Rohan Dassanayake; Erandathi Rajakaruna; Hanna Moussa; Noureddine Abidi. One-pot synthesis of MnO 2 –chitin hybrids for effective removal of methylene blue. International Journal of Biological Macromolecules 2016, 93, 350 -358.

AMA Style

Rohan Dassanayake, Erandathi Rajakaruna, Hanna Moussa, Noureddine Abidi. One-pot synthesis of MnO 2 –chitin hybrids for effective removal of methylene blue. International Journal of Biological Macromolecules. 2016; 93 ():350-358.

Chicago/Turabian Style

Rohan Dassanayake; Erandathi Rajakaruna; Hanna Moussa; Noureddine Abidi. 2016. "One-pot synthesis of MnO 2 –chitin hybrids for effective removal of methylene blue." International Journal of Biological Macromolecules 93, no. : 350-358.

Article
Published: 06 October 2016 in Angewandte Chemie International Edition
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Directly obtaining kinetic and mechanistic data for the reactions of nitroxyl (HNO) with biomolecules (k≈103–107 m−1 s−1) is not feasible for many systems because of slow HNO release from HNO donor molecules (t1/2 is typically minutes to hours). To address this limitation, we have developed a photoactivatable HNO donor incorporating the (3-hydroxy-2-naphthalenyl)methyl phototrigger, which rapidly releases HNO on demand. A “proof of concept” study is reported, which demonstrates that, upon continuous xenon light excitation, rapid decomposition of the HNO donor occurs within seconds. The amount of HNO generated is strongly dependent on solvent and the rate of the reaction is dependent on the light intensity.

ACS Style

Yang Zhou; Ruth B. Cink; Rohan Dassanayake; Alexander J. Seed; Nicola E. Brasch; Paul Sampson. Rapid Photoactivated Generation of Nitroxyl (HNO) under Neutral pH Conditions. Angewandte Chemie International Edition 2016, 55, 13229 -13232.

AMA Style

Yang Zhou, Ruth B. Cink, Rohan Dassanayake, Alexander J. Seed, Nicola E. Brasch, Paul Sampson. Rapid Photoactivated Generation of Nitroxyl (HNO) under Neutral pH Conditions. Angewandte Chemie International Edition. 2016; 55 (42):13229-13232.

Chicago/Turabian Style

Yang Zhou; Ruth B. Cink; Rohan Dassanayake; Alexander J. Seed; Nicola E. Brasch; Paul Sampson. 2016. "Rapid Photoactivated Generation of Nitroxyl (HNO) under Neutral pH Conditions." Angewandte Chemie International Edition 55, no. 42: 13229-13232.

Journal article
Published: 01 October 2016 in Journal of Inorganic Biochemistry
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Kinetic and mechanistic studies on the reaction of a major intracellular vitamin B12 form, cob(II)alamin (Cbl(II)), with hypochlorous acid/hypochlorite (HOCl/OCl−) have been carried out. Cbl(II) (Co(II)) is rapidly oxidized by HOCl to predominately aquacobalamin/hydroxycobalamin (Cbl(III), Co(III)) with a second-order rate constant of 2.4 x 107 M− 1 s− 1 (25.0 °C). The stoichiometry of the reaction is 1:1. UHPLC/HRMS analysis of the product mixture of the reaction of Cbl(II) with 0.9 mol equiv. HOCl provides support for HOCl being initially reduced to Cl• and subsequent H atom abstraction from the corrin macrocycle occurring, resulting in small amounts of corrinoid species with two or four H atoms fewer than the parent cobalamin. Upon the addition of excess (H)OCl further slower reactions are observed. Finally, SDS-PAGE experiments show that HOCl-induced damage to bovine serum albumin does not occur in the presence of Cbl(II), providing support for Cbl(II) being an efficient HOCl trapping agent.

ACS Style

Rohan Dassanayake; Mohamed M. Farhath; Jacob T. Shelley; Soumitra Basu; Nicola E. Brasch. Kinetic studies on the reaction of cob(II)alamin with hypochlorous acid: Evidence for one electron oxidation of the metal center and corrin ring destruction. Journal of Inorganic Biochemistry 2016, 163, 81 -87.

AMA Style

Rohan Dassanayake, Mohamed M. Farhath, Jacob T. Shelley, Soumitra Basu, Nicola E. Brasch. Kinetic studies on the reaction of cob(II)alamin with hypochlorous acid: Evidence for one electron oxidation of the metal center and corrin ring destruction. Journal of Inorganic Biochemistry. 2016; 163 ():81-87.

Chicago/Turabian Style

Rohan Dassanayake; Mohamed M. Farhath; Jacob T. Shelley; Soumitra Basu; Nicola E. Brasch. 2016. "Kinetic studies on the reaction of cob(II)alamin with hypochlorous acid: Evidence for one electron oxidation of the metal center and corrin ring destruction." Journal of Inorganic Biochemistry 163, no. : 81-87.

Journal article
Published: 24 February 2016 in Journal of Materials Chemistry A
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Amidoxime-functionalized microcrystalline cellulose–mesoporous silica composites for CO 2 sorption. Amidoxime-functionalized microcrystalline cellulose (MCC)–mesoporous silica composites were prepared for the first time by a two-step process. First, microcrystalline cellulose (MCC)–mesoporous silica with cyanopropyl groups (MCC-CP) was obtained by solvent evaporation-induced self-assembly of MCC, tetraethylorthosilicate, and (3-cyanopropyl)triethoxysilane in the presence of a Pluronic P123 triblock copolymer under acidic conditions. In the next step, the resulting material was treated with hydroxylamine hydrochloride to convert cyanopropyl groups into amidoxime functionalities to obtain a mesoporous MCC-AO composite. A series of MCC-CP and MCC-AO samples was examined for CO 2 sorption at ambient (25 °C) and elevated (120 °C) temperatures. While the MCC-CP and MCC-AO samples showed relatively low CO 2 uptake under ambient conditions, they performed very well at elevated temperatures (120 °C) reaching CO 2 sorption capacities of 2.15–2.41 mmol g −1 (MCC-CP) and 2.84–3.85 mmol g −1 (MCC-AO). The CO 2 sorption capacity of MCC-AO at 120 °C exceeds the values reported so far for many other sorbents, which makes this material attractive for CO 2 capture in addition to its biocompatibility, biodegradability, non-toxicity, low cost, cycle stability, and good thermal and mechanical stability.

ACS Style

Chamila Gunathilake; Rohan Dassanayake; Noureddine Abidi; Mietek Jaroniec. Amidoxime-functionalized microcrystalline cellulose–mesoporous silica composites for carbon dioxide sorption at elevated temperatures. Journal of Materials Chemistry A 2016, 4, 4808 -4819.

AMA Style

Chamila Gunathilake, Rohan Dassanayake, Noureddine Abidi, Mietek Jaroniec. Amidoxime-functionalized microcrystalline cellulose–mesoporous silica composites for carbon dioxide sorption at elevated temperatures. Journal of Materials Chemistry A. 2016; 4 (13):4808-4819.

Chicago/Turabian Style

Chamila Gunathilake; Rohan Dassanayake; Noureddine Abidi; Mietek Jaroniec. 2016. "Amidoxime-functionalized microcrystalline cellulose–mesoporous silica composites for carbon dioxide sorption at elevated temperatures." Journal of Materials Chemistry A 4, no. 13: 4808-4819.

Journal article
Published: 16 February 2016 in Cellulose
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Activated carbon was prepared from cellulose-based aerogel (aerocellulose) monoliths by carbonization and subsequent CO2 activation. The monolithic structure of the as-synthesized aerocellulose was retained during the carbonization and activation processes. The as-synthesized aerocellulose monolith was mainly mesoporous with well-developed surface area, large total pore volume, with only moderate CO2 uptake. In order to enhance CO2 adsorption, microporosity of carbonized aerocellulose was increased upon CO2 activation. The resulting activated carbon showed an enhanced specific surface area of ~750 m2 g−1, total pore volume of 0.43 cm3 g−1, and volume of micropores (pore widths <2 nm) of ~0.27 cm3 g−1. Activation of carbonized aerocellulose resulted in about five-fold increase in the specific surface area and over 27-fold increase in the volume of micropores as compared to the as-synthesized material. The resulting activated carbon showed excellent adsorption properties toward CO2 reaching 5.8 mmol g−1 of CO2 at 0 °C and 1 atm and 3.7 mmol g−1 of CO2 at 25 °C and 1.2 atm. High microporosity and surface area of the activated aerocellulose-derived carbon combined with its biocompatibility, biodegradability, non-toxicity, low cost, and good thermal stability makes this material beneficial for CO2 capture at ambient temperatures.

ACS Style

Rohan Dassanayake; Chamila Gunathilake; Tanya Jackson; Mietek Jaroniec; Noureddine Abidi. Preparation and adsorption properties of aerocellulose-derived activated carbon monoliths. Cellulose 2016, 23, 1363 -1374.

AMA Style

Rohan Dassanayake, Chamila Gunathilake, Tanya Jackson, Mietek Jaroniec, Noureddine Abidi. Preparation and adsorption properties of aerocellulose-derived activated carbon monoliths. Cellulose. 2016; 23 (2):1363-1374.

Chicago/Turabian Style

Rohan Dassanayake; Chamila Gunathilake; Tanya Jackson; Mietek Jaroniec; Noureddine Abidi. 2016. "Preparation and adsorption properties of aerocellulose-derived activated carbon monoliths." Cellulose 23, no. 2: 1363-1374.

Journal article
Published: 11 November 2015 in The Journal of Neuroscience
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Mitochondrial changes, including decreased expression of electron transport chain subunit genes and impaired energetic, have been reported in multiple sclerosis (MS), but the mechanisms involved in these changes are not clear. To determine whether epigenetic mechanisms are involved, we measured the concentrations of methionine metabolites by liquid chromatography tandem mass spectrometry, histone H3 methylation patterns, and markers of mitochondrial respiration in gray matter from postmortem MS and control cortical samples. We found decreases in respiratory markers as well as decreased concentrations of the methionine metabolites S-adenosylmethionine, betaine, and cystathionine in MS gray matter. We also found expression of the enzyme betaine homocysteine methyltransferase in cortical neurons. This enzyme catalyzes the remethylation of homocysteine to methionine, with betaine as the methyl donor, and has previously been thought to be restricted to liver and kidney in the adult human. Decreases in the concentration of the methyl donor betaine were correlated with decreases in histone H3 trimethylation (H3K4me3) in NeuN+ neuronal nuclei in MS cortex compared with controls. Mechanistic studies demonstrated that H3K4me3 levels and mitochondrial respiration were reduced in SH-SY5Y cells after exposure to the nitric oxide donor sodium nitroprusside, and betaine was able to rescue H3K4me3 levels and respiratory capacity in these cells. Chromatin immunoprecipitation experiments showed that betaine regulates metabolic genes in human SH-SY5Y neuroblastoma cells. These data suggest that changes to methionine metabolism may be mechanistically linked to changes in neuronal energetics in MS cortex.

ACS Style

Naveen Kumar Singhal; Shuo Li; Erland Arning; Kholoud Alkhayer; Robert Clements; Zachary Sarcyk; Rohan Dassanayake; Nicola E. Brasch; Ernest J. Freeman; Teodoro Bottiglieri; Jennifer McDonough. Changes in Methionine Metabolism and Histone H3 Trimethylation Are Linked to Mitochondrial Defects in Multiple Sclerosis. The Journal of Neuroscience 2015, 35, 15170 -15186.

AMA Style

Naveen Kumar Singhal, Shuo Li, Erland Arning, Kholoud Alkhayer, Robert Clements, Zachary Sarcyk, Rohan Dassanayake, Nicola E. Brasch, Ernest J. Freeman, Teodoro Bottiglieri, Jennifer McDonough. Changes in Methionine Metabolism and Histone H3 Trimethylation Are Linked to Mitochondrial Defects in Multiple Sclerosis. The Journal of Neuroscience. 2015; 35 (45):15170-15186.

Chicago/Turabian Style

Naveen Kumar Singhal; Shuo Li; Erland Arning; Kholoud Alkhayer; Robert Clements; Zachary Sarcyk; Rohan Dassanayake; Nicola E. Brasch; Ernest J. Freeman; Teodoro Bottiglieri; Jennifer McDonough. 2015. "Changes in Methionine Metabolism and Histone H3 Trimethylation Are Linked to Mitochondrial Defects in Multiple Sclerosis." The Journal of Neuroscience 35, no. 45: 15170-15186.