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This current study was conducted to investigate the optimal fabrication variable that would give desirable properties in designing hydrogel wound dressings. This new PVA/chitosan hydrogel loaded with Chromolaena odorata were fabricated using solvent-casting method. Variables including PVA concentration (3, 5, 7 and 10% w/v), chitosan concentration (1, 2, 3, 4 and 5% w/v) and PVA/Chitosan ratio (10:90, 30:70, 50:50, 70:30 and 90:10) were investigated and elucidated. Hydrogel properties including tensile strength, swelling capacity, erosion rate and porosity were measured and effects of the fabrication variables towards these properties were elucidated. In conclusion, desirable PVA/Chitosan hydrogel loaded with Chromolaena odorata extract as wound dressing was favorly designed. The optimal range for PVA concentration, chitosan concentration and PVA/Chitosan ratio were 5% to 7%, 2% to 3% and 50:50 to 70:30 respectively.

Dynamic light scattering (DLS) or photon cross-correlation spectroscopy (PCCS) is a very potent means for analyzing the diffusion behaviour of supramolecules in their solution form. The diffusion coefficient, probed from the scattered light by supramolecules underexposure to incident light, allows the hydrodynamic radii to be calculated. However, the scattering values were recently misled by an unexpected interaction between the incident light and thermo-sensitive nanogels. Hence, in turn, it resulted in a miscalculation of the size of the nanogels by more than 100% of their expected values. The study fulfills a vital knowledge gap by investigating the effects of laser intensity on the size of thermo-sensitive Poly(N-Isopropyl Acrylamide-Vinyl Pyrrolidone-Polyethylene Glycol Diacrylate-(2-(Dimethyl Amino)Ethyl Methacrylate)), Poly(NIPAAM-PVP-PEGDA-DMAEMA) nanogels and subsequent count rates in DLS measurements. The Lower Critical Solution Temperature, LCST phase transition of Poly(NIPAAM-PVP-PEGDA-DMAEMA) nanogel can be observed using the DLS technique. The higher laser intensity was advantageous for measuring at high dilution more vigorously with varying laser intensities. Thus, a sufficient laser intensity should be chosen based on the light scattering characteristics of typical samples.

This chapter aims to provide the reader with some information about the possibility of starch as a suitable substitute for synthetic polymers in biodegradable food packaging. This is due to the starch has good characteristics which are great biodegradability, low cost and also easy to gain from natural resources. However, some of technical challenges are also introduced before starch-based polymers can be used in more applications. These technical challenges involved preparation methods and incorporation of additives and these are being summarized in this topic. Hence, the enhancement of starch can be done in order to prepare innovative starch-based biodegradable materials.

Nanotechnology also called as nanotech is referring to the science, technology and engineering to synthesis, manipulation and investigation of materials and devices at nanoscales. Nanoparticles (NPs) owns a special place in nanotechnology due to their extreme-small size, multifunctionality, and modifiable surface for wide range of applications especially in new drug delivery application as the stability, solubility, biocompatibility and drugs releasing of NPs are highly controllable. The variation of nanomaterials with different physiochemical and morphological properties will affect the materials-living cells interaction and determination of the route of clearance and potential toxic effects. Thus, it requires more cross-disciplinary research on the designing and developing of drugs delivery NPs based on the diagnosis and treatment of devastating diseases. Biopolymers-based NPs have gained great attention for drug delivery system over the past few decades compared to other materials-based NPs such as liposomes, ceramics and lipids as well as magnetic NPs. There are extensive studies and developments of biopolymers-based NPs for drug delivery and tissue engineering as it capable of controlling the release of drugs, stabilizing labile molecules from degradation, and site-specific drug targeting. Alginate is an anionic copolymer that extracted from algae. The NPs composed alginate have become one of the most extensively researched materials for biomedical applications such as tissue engineering, wound dressing, protein/enzyme carrier and drug delivery due to its biodegradability, biocompatibility, non-toxicity and mucoadhesive properties. Furthermore, by physiochemical crosslinking and cooperating with other polymers, the mechanical strength, cell affinity and drug release profile can be modified and improved. In this brief review paper, several aspects about using alginate or crosslinked alginate for drug delivery application will be discussed, mainly focus on the structure and properties of alginate such as biocompatibility, immunogenicity and biodegradability, as well as the effect of mucoadhesion and pH sensitivity of using alginate in drug delivery nanoparticles developments.

In vanadium redox flow battery (VRFB), the active area for charge-discharge plays an important role on the optimization of the system. In this work, the optimum flow rate and current density of Nafion 117 membranes were examined and compared using 5cm2 and 25cm2 size of interdigitated flow field to operate VRFB at maximum efficiencies and discharge capacity. During discharge, flow field 25cm2 showed the highest discharge capacity of 367.5mAh at 10mAcm-2 as compared to 5cm2 flow filed which gave 221.9mAh. For battery efficiencies, three different parameters showed significant effects on different size of interdigitated flow field. 25 cm2 size of interdigitated flow field gave higher efficiencies than 5.0 cm2 up to 98%. This research offers fundamental understandings that bigger active area is needed to fully utilize the performance of VRFB.

The influence of 2-(dimethylamino)ethyl methacrylate (DMAEMA) concentration on the temperature sensitivity of nanogels based on N-isopropylacrylamide (NIPAAM), poly(vinylpyrrolidone) (PVP), poly(ethylene glycol) diacrylate (PEGDA) by gamma radiation induced polymerization was investigated. Dynamic light scattering (DLS) and zeta potential measurements were used to characterize the nanogels. Temperature has been found to cause the nanogel particles to swell and shirnkage, allowing controlled dosing of the drug contained in capsules. The developed nanogels are promising materials with great potential for biomedical applications.

Dyes are coloured compound which are widely used in textile, painting, rubber, cosmetics, plastics and leather industry to colour their products. However, the irresponsibility of certain manufacturer results in producing dye waste and channel it to water resources had become one of the biggest challenges in water pollution. In this study, an effective solid adsorbent derived from sustainable sources for adsorption capacity study was produced which is silver nanoparticles loaded activated carbon (Ag NPs – AC) to remove crystal violet (CV) dye. Adsorption process are cost – effective, simple and flexible with various dye pollutants. Silver nanoparticles (Ag NPs) was synthesized from Clitorea Ternatea flower extract that utilizes functions as stabilizing agents for silver nitrate (AgNO3) to promotes environmental friendly with no toxic chemicals produced and loaded in activated carbon (AC). Characterization of Ag NPs was analysed using UV-Visible which correspond to peak at 408 nm and XRD analysis. Four peaks values for silver at 2θ of 38.19°, 44.43°, 64.57°, 77.43° and average crystallite size of Ag NPs and Ag NPs – AC were calculated to be 16.11 nm and 36.13 nm respectively that were obtained from XRD pattern. The adsorption capacity of Ag NPs – AC was analysed and the optimum conditions were determined using different parameters which are the Ag NPs - AC ratio (1.0 g), contact time (240 min), adsorbent dosage (30 mg) and pH of CV dye (10). The highest percentage removal of CV dye using Ag NPs – AC was recorded up to 97% at 240 min with 30 mg dosage. Ag NPs – AC as adsorbent is a promising advanced materials in removing water pollutants with viable conditions and can applied in the wastewater treatment industry.

Chitosan nanoparticles (ChNPs) have been extensively examined for various biomedical applications due to their advantages include large surface area, biodegradability, and biocompatibility. The purpose of this research was to synthesize ChNPs using a simple ionic gelation technique by the interaction of low molecular weight chitosan (LMWC) and sodium tripolyphosphate (TPP) as a cross-linking agent. ChNPs, TPP, and LMWC were analysed by X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectra that indicated the formation of ChNPs, attributing to the rearrangement of the nanoparticles after adding the TPP cross-linker into the LMWC solution. XRD analysis exhibited that ChNPs were amorphous, due to the effect of TPP cross-linker. Dynamic light scattering showed the nano-dimension of ChNPs with a hydrodynamic size of 68.50 nm. Thus, the obtained results indicated that the properties of chitosan were improved through converting it into nanoparticles using TPP initiated ionic gelation procedure.

The present paper reports the synthesis of silver nanoparticles (Ag-NPs) by a green method using Hibiscus sabdariffa (H. sabdariffa) leaves extract as reductant and stabilizer. The synthesized Ag-NPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). UV-vis spectrum of synthesized Ag-NPs showed a peak at 378 nm. TEM analysis revealed that the particles were spherical and irregular in shape and has average size around 56.52 nm. This structure and size of particles were confirmed by AFM analysis. The UV-vis and FTIR spectrum provides evidence of the presence of caffeic acid component as a representative biomolecule in stabilising the nanoparticles based on previous studies. Hence, this study advocates that H. sabdariffa have potential for synthesizing nanoparticles.

In this studies, synthesis of silver nanoparticles (Ag-NPs) on pullulan-based biofilm was achieved by microwave irradiation technique. Synthesis of Ag-NPs was achieved using pullulan as both a reducing and stabilizing agent. The effect of different microwave irradiation duration on pullulan and silver nitrate in synthesis of silver nanoparticles (Ag-NPs) was investigated. The synthesized Ag-NPs/PL were first screened and identified using surface plasmon peaks of UV–Vis spectroscopy. The research results indicated that the surface plasmon resonance peaks were observed between 400–414 nm wavelengths in UV-VIS spectroscopy studies. From Fourier-transform infrared spectroscopy (FTIR) spectra, stretching vibrations of hydroxyl (OH), carbonyl (C=O) and C=C stretches exhibits the reduction and stabilization of Ag-NPs. Further, five characteristic peaks Ag(111), Ag(200), Ag(210), Ag(220) and Ag(311) confirmed the presence of elemental silver and the crystalline structure of silver nanoparticles from X-ray Diffraction analysis. Biofilms were produced by mixing the synthesized Pulullan-Ag-NPs with polyvinyl alcohol. The AgNP/PL were applied for the antimicrobial activity against Bacillus subtilis and found to have high antibacterial activity. In addition, the clear zones of inhibition was found at 11 mm to 16 mm against Bacillus Subtillis. The experimental results demonstrated that pullulan could be used as reducing and stabilizing agent for formation of Ag-NPs.

Magnetite nanoparticles (Fe3O4 NPs) have received considerable attention in various biomedical applications due to their fascinating properties and multiple functionalities. In this multidisciplinary study, Fe3O4 NPs were produced by an inexpensive co-precipitation technique and using four different weight percentages of Punica granatum fruit peel extract as a green stabilizer. From the image of transmission electron microscopy, the NPs showed spherical shapes with an average size of 14.38 nm. Results of UV–VIS spectroscopy and bandgap indicated successful preparation of the Fe3O4 NPs stabilized with the extract. Adding the stabilizer concentration improved the particle zeta potential from −29.24 to −35.62 mV. Thermoresponsive performance of the Fe3O4 nanofluids with the green extract could render a remarkable heating capability under the hyperthermia condition. Magnetic resonance imaging (MRI) analysis presented that the samples possessed acceptable MRI signals. An anticancer drug 5-fluorouracil was successfully loaded onto the Fe3O4 NPs containing 2 weight percentage of the extract, which indicated a maximum release of 79% in a media with pH 7.4. In cytotoxicity assays, the drug-loaded Fe3O4 NPs at 15.62 and 31.25 µg.ml−1 concentration eliminated 29% and 35% of HCT116 colorectal cancer cells, respectively. This study, therefore, introduced that the green-synthesized Fe3O4 NPs can be a promising candidate for magnetic hyperthermia therapy, MRI nanoagents and drug delivery in colorectal cancer.

Polyvinylidene Fluoride (PVDF) has been used as a membrane’s base material for wastewater treatment for quite some time. Due to PVDF hydrophobic nature, fouling will occur, thus, reducing the membrane performance. The main objective of this study was to investigate the effect of various chitosan loadings on membrane hydrophilicity and overall liquid separation performance. The loadings of chitosan (wt.%) used were neat PVDF, 0.25%, 0.5%, 0.75% and 1% in PVDF mixed matrix membrane. It was found that 0.75% chitosan membrane had the lowest contact angle of 63° making it the most hydrophilic. The pure water flux test on the membranes also showed the same trend where the lowest contact angle resulting in the highest pure water flux. The PVDF membrane containing 0.75% chitosan possessed the highest pure water flux of 43.5 Lm−2h−1. With the rejection of dye of over 43.12%. The study proved that adding chitosan into PVDF membrane certainly improved the membrane hydrophilicity and the percentage removal of methylene blue dye.

The production of pure silver nanoparticles (Ag-NPs) with unique properties remains a challenge even today. In the present study, the synthesis of silver nanoparticles (Ag-NPs) from natural pullulan (PL) was carried out using a radiation-induced method. It is known that pullulan is regarded as a microbial polysaccharide, which renders it suitable to act as a reducing and stabilizing agent during the production of Ag-NPs. Pullulan-assisted synthesis under gamma irradiation was successfully developed to obtain Ag-NPs, which was characterized by UV-Vis, XRD, TEM, and Zeta potential analysis. Pullulan was used as a stabilizer and template for the growth of silver nanoparticles, while gamma radiation was modified to be selective to reduce silver ions. The formation of Ag-NPs was confirmed using UV–Vis spectra by showing a surface plasmon resonance (SPR) band in the region of 410–420 nm. As observed by TEM images, it can be said that by increasing the radiation dose, the particle size decreases, resulting in a mean diameter of Ag-NPs ranging from 40.97 to 3.98 nm. The XRD analysis confirmed that silver metal structures with a face-centered cubic (FCC) crystal were present, while TEM images showed a spherical shape with smooth edges. XRD also demonstrated that increasing the dose of gamma radiation increases the crystallinity at a high purity of Ag-NPs. As examined by zeta potential, the synthesized Ag-NP/PL was negatively charged with high stability. Ag-NP/PL was then analysed for antimicrobial activity against Staphylococcus aureus, and it was found that it had high antibacterial activity. It is found that the adoption of radiation doses results in a stable and green reduction process for silver nanoparticles.

The search of new membranes for vanadium redox flow battery with low vanadium ions permeation rates, high ion conductivity, excellent proton conductivity, low area resistance, chemical stability, and low cost is on a soaring demand. In this work, a simple modification method is applied to improve the performance of commercially available low-cost membranes by applying several polyelectrolytes layers. Particularly, graphene-containing commercial perfluorinated sulfonic acid membrane of GN212C with a thickness of 33 μm is modified by introducing alternate layers of positively charged poly(diallyldimethylammonium chloride) and negatively charged poly(sodium styrene sulfonate). Microscopy and spectroscopy investigations indicate that the polyelectrolytes layers are successfully deposited on the membrane surface. The effects of the layer composition and number of bilayers are evaluated with regard to vanadium ion permeability, proton conductivity and battery performance. The modified membranes exhibit an improved vanadium (VO2+) barrier property, which enhances the VRFB single cell performance in terms of coulombic efficiency and energy efficiency compared to pristine GN212C and Nafion 117 membranes. The overall results suggest that the bi-ionically modified membrane is a potential candidate for application in flow battery despite its small thickness.

In this study, gold nanoparticles (Au-NPs) were synthesized through green biosynthetic route using water extract of Hibiscus sabdariffa leaves (H. sabdariffa L.) which acted as both reductant and stabilizer agents. The synthesized Au-NPs were characterized by UV–vis spectroscopy, XRD, TEM, FESEM, EDX, zeta potential, and FTIR spectroscopy. By analyzing the UV–vis, FTIR and HPLC data, and comparing with previous studies, the presence of chlorogenic acid in H. sabdariffa L. was identified as the major antioxidant compound involved in the reduction of Au3+ ions. The FESEM micrograph and TEM images visualized that Au-NPs were formed with a narrow distribution and an average particle size of 7 ± 2 nm at stirring time of 80 min. As for application, the electrooxidation of nitrite was studied with Au-NPs. The electrocatalytic activity of bare GCE and Au-NPs/GCE towards the electrooxidation of nitrite was examined and compared via cyclic voltammetry. Higher electrooxidation of nitrite ions for the synthesized Au-NPs was observed at a stirring time of 80 min. The prepared material showed a linearity of 0.37–10 mM towards nitrite electrooxidation, with the limit of detection (LOD) of 0.11 mM (S/N = 3). Moreover, the prepared electrode presented acceptable stability, repeatability and reproducibility.

A series of magnetite nanoparticles were prepared with electrosynthesis. Natural capping agent, sodium alginate (SA) was added to electrolysis system to produce smaller size and highly crystalline of magnetite. The variation of SA content highly influenced the particle size which confirmed with XRD. FTIR characterization confirmed that SA interact with magnetite surface. The magnetite product was also evaluated for paracetamol (PCT) degradation as a sample of pharmaceutical waste due to its large consumption in society. The highest initial degradation rate (8.22 x 10-2 mg/L.min) was achieved with magnetite which is prepared from 0.05% w/v of SA at initial concentration of 15 mg/L PCT. Finally, the result could contribute to electrosynthesis advancement of magnetite with high purity using inexpensive and green chemicals.

The variations in the consumption load and generation power in microgrid systems such as photovoltaic, wind-turbine fuel cell and energy storage systems (PV/WT/FC/ESSs) has challenged the load-frequency control due to the increased complexity and nonlinear nature of these systems. This paper employs a self-tuning controller based on the fuzzy logic to overcome parameter uncertainties of classic controllers, such as operation conditions, the change in the operating point of the microgrid and the uncertainty of microgrid modeling. Further, a combined fuzzy logic and fractional-order controller is used for load-frequency control of the off-grid microgrid with the influence of renewable resources because the latter controller benefits robust performance and enjoys a flexible structure. To reach a better operation for the proposed controller, a novel meta-heuristic whale algorithm has been used to optimally determine the input and output scale coefficients of the fuzzy controller and fractional orders of the fractional-order controller. The suggested approach is applied to a microgrid with a diesel generator, wind turbine, photovoltaic systems, and energy storage devices. The comparison made between the results of the proposed controller and those of the classic PID controller proves the superiority of the optimized fractional-order self-tuning fuzzy controller in terms of operation characteristics, response speed, and the reduction in frequency deviations against load variations.

Polysulfone (PSf) membranes are becoming more popular in wastewater treatment recently, mostly due to its stability in chemical, thermal and mechanical properties. PSf membranes are hydrophobic, causing difficulty of water permeation. Incorporating metal oxide nanoparticles improving the membrane hydrophilicity, thus increasing membrane permeation and rejection. In this study, copper oxide nanoparticle (CuO NPs) incorporated PSf membranes were fabricated under different evaporation times of 3s, 6s, 8s, and 9s to investigate on membrane morphology and performance. The membrane morphologies were characterized by using scanning electron microscope (SEM) while the membrane performance was determined through pure water flux (PWF) and bovine serum albumin (BSA) rejection. When characterized by SEM, all membranes showed an asymmetric structure with thin and dense at the top while the bottom layer was thick and porous. It was discovered that as the evaporation time increased, the formation of the finger-like structure became narrower while dense layer became thicker. When tested with PWF, membranes with higher evaporation times showed less permeability, decreasing from 139.74 Lm-2h-1 to 89.89 Lm-2h-1. In terms of BSA rejection, increased in evaporation time caused the rejection rate to increase from 87.79% to 92.15%. This study proved that evaporation time is one of important parameters that influences the membrane performance significantly.

The main objective of the current work is to investigate the influence of catalyst to biomass ratio (by weight%) on the catalytic upgrading of sugarcane bagasse derived pyrolysis vapours over cerium (Ce) loaded Hydrogen exchanged Zeolite Socony Mobil-5 (HZSM-5) catalyst via in-situ fixed bed reactor. The temperature of pyrolysis was kept at 500 °C for all investigated samples. The HZSM-5 catalyst was used as a support with 1 wt% of Ce as promoter loaded via incipient wetness impregnation method. The biomass sample was fixed at 2 g, while the catalyst mass loading was loaded according to the catalyst to biomass ratio which are 0.5:1.0, 1.0:1.0, 1.5:1.0, and 2.0:1.0. For comparison, the non-catalytic and biomass catalytic over HZSM-5 catalyst was also pyrolyzed at the same operating conditions. The results show that the yields of pyrolysis oil and coke were significantly influenced by the use of Ce/HZSM-5 catalyst at various catalyst to biomass ratio than the catalytic pyrolysis over HZSM-5, in which generate higher pyrolysis oil yield (58.0–68.0 wt%) and lower coke yield (2.9–4.1%). The increasing loading of mass in Ce/HZSM-5 catalyst has additional effect with respect to C6–C8 hydrocarbon contents in pyrolysis oil than the catalytic samples over the HZSM-5 catalyst. Among the tested catalyst to biomass ratio, the catalyst to biomass ratio of 1.5:1 has demonstrated to be the potential candidates in the catalytic upgrading of sugarcane bagasse derived oxygenated pyrolysis vapours into higher content of C6–C8 hydrocarbons (2.45%) in pyrolysis oil with lower coke yield (3.2%) over Ce/HZSM-5 catalyst. The bi-functional Ce/HZSM-5 catalyst was more effective in suppressing the coke formation in comparison to HZSM-5 catalyst at all investigated catalyst to biomass ratios and this was attributed to the synergistic effect of Ce on HZSM-5 support.

Magnetic polymer nanocomposites are inherently multifunctional and harbor assorted physiochemical actions for applications thereof as novel drug nanocarriers. Herein, Fe3O4-nanoparticles were supported on rice straw cellulose for 5-fluorouracil carrier abbreviated as MC/5-FU for potential colorectal cancer treatments. Several analyses indicated the multifunctional properties of MC/5-FU bionanocomposites. Transmission and scanning electron microscopy study demonstrated that Fe3O4 nanofillers covered the cellulose matrix. The drug release from MC/5-FU was evaluated under various pH and temperature conditions, showing the maximum release at pH 7.4 and 44.2 °C. In in vitro anticancer assay, MC/5-FU exhibited enhanced selectivity and anticancer actions against 2D monolayer and 3D tumour spheroid models colorectal cancer cells. The anticancer effects of MC/5-FU with magnetic targeting and heat induction were also examined. This easily synthesized MC/5-FU indicated the potential in application as a low-cost drug formulation for colorectal cancer treatments.

The main objective of the present work is to investigate the influence of catalyst to biomass ratio (C:B) on pyrolysis sugarcane bagasse over cerium loaded Hydrogen exchanged Zeolite Socony Mobil-5 (HZSM-5, Si/Al = 23) catalyst via in-situ fixed bed reactor. HZSM-5 catalyst was used as a support with 1 wt.% of Ce as promoter loaded via incipient wetness impregnation method. The pyrolysis oil (PO) yield and coke yield were significantly affected by the use of Ce/HZSM-5 at various C:B ratio than the none catalytic pyrolysis, in which generating low PO yields (50.0 wt.%). The increasing Ce/HZSM-5 loading has an additional effect with respect to PO and coke yields. Among the tested C:B ratio, a catalyst to biomass ratio of 1:1 has demonstrated to be potential candidates in the catalytic pyrolysis of SB into a higher yield of condensable pyrolysis oil with lower coke contents.

The main objective of the present work is to study the effect of Nickel-Cerium/Alumina multifunctional catalyst (Ni-Ce/Al2O3) mass loading on pyrolysis of coconut copra and rice husk via thermogravimetric analysis. The sample is pyrolyzed from 30 °C up to 700 °C at a constant heating rate of 10 °C/min in nitrogen environment flowing at 150 mL/min. The multifunctional catalyst (Ni-Ce/Al2O3) was prepared via incipient wet impregnation method. Pyrolysis feedstocks were prepared based on biomass to catalyst mass loading ratio. The TG-DTG curve shows that the presences of catalyst significantly affect the devolatilization rate of biomass. Among TGA-pyrolyzed coconut copra samples, the CC-3 (1:0.15) has achieved the highest mass loss (83.3%). For rice husk, the non-catalytic sample has attained the highest mass loss of volatile matter (48.7%). In addition, the kinetic characteristics of non-catalytic and catalytic pyrolysis of biomass were also studied and calculated by employing the Coats-Redfern integral method. The CC-1 has lower activation energy (53.10 kJ/mol) than that of catalytic sample particularly CC-3 (79.28 kJ/mol). The presence of a catalyst on rice husk is able to reduce the activation energy of non-catalytic rice husk sample from 49.78 to 45.24 kJ/mol.

In the last several years, the interest on hydrophobic and hydrophilic solid subtract was increased due to many applications in daily life, agriculture and industry. The continuous effort has been made to fabricate suitable material with more efficient fabrication method. In this research, physical blending method have been used by mixing four components of modifying agent with organic beeswax varnish at different weight percentage. Those modifying agents consists of decamethylcyclopentasiloxane (D5), Silica nanoparticles (R812S), Polydimethylsiloxane (BP-9400) and non-ionic surfactant (Triton X-100) were mixed in the mass ratio of 52:3:34:1. The modified varnish produced was coated on Pineapple peel fiber (PAPF) biocomposite and were characterized using Water Contact Angle (WCA) instrument, Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). Based on the wettability index analysis; the value of water contact angle was reduced when increasing weight percent of modifying agents from 101.87 to 22.98°. The morphology of the surface was observed to have more silica nanoparticles, along with the increasing concentration of modifying agent. It also supported by FTIR which shows the presence of Si-O peak at 1030.88 cm-1. These results proved that the modifying agent and organic beeswax varnish had successfully produced hydrophilic coated on the PAPF surface.

Graphene oxide (GO) has attracted tremendous attention in membrane-based separation field as it can filter ions and molecules. Recently, GO-based materials have emerged as excellent modifiers for vanadium redox flow battery (VRFB) application. Its high mechanical and chemical stability, nearly frictionless surface, high flexibility, and low cost make GO-based materials as proper materials for the membranes in VRFB. In VRFB, a membrane acts as the key component to determine the performance. Therefore, employing low vanadium ion permeability with excellent stability membrane in vanadium electrolytes is important to ensure high battery performance. Herein, recent progress of GO-modified membranes for VRFB is briefly reviewed. This review begins with current membranes used for VRFB, followed by the challenges faced by the membranes. In addition, the transport mechanism of vanadium ion and the stability properties of GO-modified membranes are also discussed to enlighten the role of GO in the modified membranes.

Preparation and optimization of tetraethylenepentamine (TEPA) content in polyethylene/polypropylene (PE/PP) grafted with poly(glycidyl methacrylate) (PGMA) adsorbent for CO2 capture were investigated. The amination reaction parameters such as solvent type, amine to solvent ratio and reaction time were optimized using the Taguchi method to maximize the level of amination in the adsorbent. The obtained data were statistically analysed using the analysis of variance (ANOVA) and signal to noise (S/N) ratio. The chemical, morphological, structural, and thermal properties of the aminated fibrous adsorbent were investigated using Fourier transform infrared (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). The performance of the obtained TEPA-containing fibrous adsorbent was evaluated for adsorption of pure and mixed CO2/N2 gases under varying pressure up to 30 bar. The optimization of the amination parameters led to an adsorbent with improved properties in forms of not only 23% higher amination level and 27% greater TEPA utilisation efficiency but also 31.6% bigger CO2 adsorption capacity than its corresponding adsorbent obtained without optimization. The adsorbent also demonstrated high CO2/N2 selectivity and regeneration stability. The results suggest that the obtained TEPA-containing fibrous adsorbent is a promising candidate for CO2 capture from CO2/N2 gaseous mixture under various pressures.

In this paper, a brief review on the preparation of copper nanoparticles (Cu-NPs) is discussed which highlighted more on the green biosynthesis route. Copper nanoparticles have been proved by numerous of researchers on their capability to be used in wide range applications due to their unique properties apart of a low cost metal compared to the noble metal nanoparticles. Nowadays, green biosynthesis method has been favoured among researchers especially those study related with biological applications due to its simple, non-toxic and environmental friendly as compared to the physical and chemical method. Even though some of the green materials have both functions which act as stabilizing agent and reducing agent in the preparation of Cu-NPs, however, some of them need a booster which also must be a green material. So, ascorbic acid which is vitamin C that has been proven with its capability to act as stabilizing and reducing agent in most of previous studies also included in this short review.

The broad range of nanotechnology applications makes it an immensely developing field especially form the areas of science and technology. A facile and eco-friendly biosynthesis approach was introduced in this study. The aqueous flower extract of Clitoria ternatea (CT) is used to reduce gold ions, gold(III) chloride trihydrate (HAuCl ·3H O) to gold nanoparticles (Au-NPs). The effect of reaction time (15 min, 60 min) was changed to determine the outcome of the size of nanoparticles. CT flower extract plays an essential part in producing Au-NPs which act as a stabilizing and reducing (Au3+ to Au) agent to reduce the consumption of harmful substances during the synthesis of CT/Au-NPs. Furthermore, it also cut down the production of unnecessary side product during the reaction that can cause harm to the ecosystem and surrounding. Ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy was used for quantification of CT/Au-NPs synthesized form different parameters. An absorption UV-vis peaks of CT/Au-NPs was noticed approximately at the range of 540 nm wavelength with different concentration of HAuCl ·3H O. X-ray diffraction was used to identify the structure and purity of synthesized CT/Au-NPs. These spectrums provide a sharp peak at around 2θ = 38.44°, 44.41°, 65.03°, and 77.58° respectively. Meanwhile, it also correlated to a face-centered cubic structure with a plane of (111), (200), (220), and (311). Furthermore, high-resolution transmission electron microscopy analysis showed the formation of highly distributed CT/Au-NPs with an average diameter of about 15.53±10.12 nm to 59.43±27.62 nm and mostly spherical. This paper has been concentrated on producing simple, cost-effective, non-toxic, and environmentally friendly nanoparticles with size controlled.

This paper reported the synthesis of copper nanoparticles (Cu-NPs) via the chemical method in the presence of CuSO4.5H20 as precursor, polysaccharide as a stabilizer and ascorbic acid was acted as a reducing agent. In this study, the irradiation time was varied to evaluate the effect of time exposure with the Cu-NPs production. The analysis of samples without and with polysaccharide was characterized using ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD) and Fourier-transform infrared coupled with attenuated total reflection instrument (ATR-FTIR). Based on the observation, reddish-brown colour solution demonstrated the formation of Cu-NPs and UV-Vis proved the plasmon resonance (SPR) spectra at the peak of 580 nm. The sharp peak of XRD at angle 2Ɵ gives the value of 43.69°, 50.81°, and 74.42° was attributed to Cu-NPs and the presence of polysaccharides maintained the crystallinity of Cu-NPs. FTIR results shows that the interaction peaks were occurred based on shifting of the peak to higher wavenumber. In conclusion, Cu-NPs were successfully produced by using the microwave method and be a function of time.

Magnetic iron oxide nanoparticles (IONPs) are increasingly being studied for potential anticancer application to circumvent off-target cytotoxicity and other side effects from conventional chemotherapy. In this study, four different weight% of Punica granatum fruit peel extract were used as green stabilizers to synthesize IONPs followed by a series of characterization experiments and in vitro anticancer evaluation. Results revealed that all synthesized IONPs have high degree of crystallinity and purity. The optimum saturation magnetization, and hydrodynamic size were found to be ∼69 emu.g−1, and 26.52 nm, respectively. Morphological studies demonstrated that adding peel extract decreased size of NPs with the average particle size below 11 nm. Cytotoxicity assay showed that the IONPs were not reactive (IC50 > 250 μg/ml) against colon (HCT116), breast (MCF7), cervical (HeLa) and lung (A549) cancer cell lines and two normal cell lines derived from human colon and kidney (CCD112 and HEK293). Specifically, IONPs with 2 and 4 wt% of peel extract displayed potent anticancer activities (IC50 of 197.46 and 85.06 μg/ml respectively) against nasopharyngeal carcinoma (NPC) cell line, HONE1. Overall, this study shows the characterization of green synthesized IONPs and its potential use as anticancer therapeutic agents against NPC cells.

In this study, ligands originated from glycidyl methacrylate (GMA) and vinyl benzyl chloride (VBC) monomers were grafted onto fibrous polyethylene/polypropylene (PE/PP) substrate and the resulting grafted copolymers were functionalized with ethylenediamine (EDA). The changes in the chemical structure and crystallinity of the aminated adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), respectively. The PE/PP-g-PGMA-EDA adsorbent showed a CO2 adsorption capacity of 1.73 mmol/g from pure gas, which is 87% lower than that of PE/PP-g-PVBC-EDA (3.24 mmol/g) at 30 bars despite the higher density in the former adsorbent. The effect of temperature, selectivity and CO2 gas composition was further investigated for the PE/PP-g-PVBC-EDA adsorbent.

A study on the effect of size and shape of copper nanoparticles (Cu-NPs) by varying the amount of honey has been done using a facile green synthesis method with the presence of ultrasonic assistance. Several amount of different % w/v of honey (0%, 1%, 5%, 10%, 15% and 20% w/v) that contain carbohydrate which are mainly glucose and fructose, and other polyhydroxyl groups act as stabilizing agent and a weak reducing agent supported by ascorbic acid were used to produce the Cu-NPs. The synthesized Cu-NPs were characterized using UV-visible, XRD and HRTEM to prove the size and shape of the nanoparticles. The best amount of honey used to produce Cu-NPs with uniform particle size and shape is at 15 % w/v. The size is 3.81 ± 1.135 nm and it shows a consistence spherical shape using HRTEM analysis image. UV-visible supported the results from the HRTEM. And XRD shows good diffraction pattern for pure Cu-NPs. It proves that honey has the ability to act as stabilizing agent in controlling the size and shape of nanoparticles.

The synthesis of gold nanoparticles (Au-NPs) is being accomplished by the reduction of aqueous gold metal ions, gold(III) chloride trihydrate (HAuCl4.3H2O) reacted with the aqueous flower extract of Clitoria Ternatea (CT). CT flower extract plays an important role in synthesizing Au-NPs. It acts as a reducing (Au3+ to Au) and stabilizing agent that can eliminate the usage of chemicals during the production of Au-NPs. Besides that, it also reduces the production of unwanted by-products which would cause hazardous to the surroundings and environment. In this study, an absorption peak of Au-NPs is observed at the range of 540-550 nm from ultraviolet-visible spectroscopy (UV-vis) analysis. Furthermore, the diffraction peaks at 2θ = 38.44°, 44.41°, 65.03° and 77.58° respectively which correspond to face-centered cubic structure with (111), (200), (220) and (311) plane confirm the successful synthesis of Au-NPs. According to transmission electron microscopy (TEM), the majority of Au-NPs are spherical in shape and having a mean particle size distribution of 18.16 nm with a standard deviation of 4.67 nm.

This paper describes a fabrication of poly (2-hydroxylethyl methacrylate) poly(HEMA) grafted on polyurethane (PU) film prepared by radiation-induced grafting (RIG) copolymerization method using electron beam irradiation for the first time. This method was well known to be fast technique, clean method without involve any chemical initiator, chemically bond the materials, and at the same time is a sterile technique suitable for further potential of biomedical application. This poly(HEMA) grafted on PU film or called as PU-g-poly(HEMA) films was analysed using Fourier-transform infrared (FTIR), scanning electron microscope (SEM), water contact angle analyser (WCA), platelet adhesion and clotting time measurement. As the results, poly(HEMA) was confirmed successful grafted on PU based on the shifting of the functional group, no significant changes in surface morphology, lowering the water contact angle from 78.28° to 70.02°, nearly no platelet adhesion and no excessive disturbance of the clotting time was observed. This means that PU-g-poly(HEMA) was improved its hydrophilicity, thus significantly reduced the platelet adhesion and maintain the normal range of time taken for blood to clot. Therefore, the present PU-g-poly(HEMA) films not only improved hydrophilicity, however, was also compatible with blood. Thus, it may be potential candidates in the biomedical devices or new biomaterial useful for future tissue engineering fields.

Green biobased polymeric membranes are being increasingly studied for different applications. In this study, freeze dried cellulose fiber with 35% yield was isolated from rice straw. The cellulose fiber was obtained through bleaching and delignification of the rice straw waste using soxhlet instrument and facile method of alkali treatment, respectively. The cellulose fiber was analysed through X-ray powder diffraction (XRD), fourier-transform infrared spectroscopy (FTIR), zeta potential analyzer and scanning electron microscope (SEM). Compared to the straw, all physicochemical properties of treated cellulose fiber increased with zeta potential up to -33.61 mV. FTIR revealed that the treatments on the straw was successful to obtain cellulose fiber with high purity. In addition, the morphological study illustrated cellulose fiber with organized structure.

Porous membrane with enhanced proton conductivity is designed and prepared for vanadium redox flow battery (VRFB). The membrane is composed of ultra height molecular weight polyethylene (UHMWPE) grafted with poly(vinylbenzyl chloride) (PVBC) at different degrees of grafting (DOG). Subsequently, the membrane is functionalized with graphene oxide (UHMWPE-g-PVBGO) under ultrasonication. The functionalization of the GO on the porous substrates is confirmed by Fourier transform infrared (FTIR) and Raman analyses. UHMWPE-g-PVBGO membranes exhibited ∼37% higher proton conductivity compared to pristine UHMWPE upon modification at 30 °C and 100% relative humidity (RH). In relation to the degree of grafting, a higher degree of grafting possessed higher proton conductivity value for the porous membrane.

The CO2 adsorption performance of poly (chloromethyl styrene) (PCMS) grafted on polyethylene coated polypropylene (PE/PP) fibrous polymer substrate and followed by amination with monoethanolamine (MEA) was investigated using gravimetric sorption system. The chemical, structural and morphological changes in the aminated adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), respectively. The amination was carried out using three different compositions of MEA (50, 80 and 100%) diluted in water to optimize the yield of loaded amine. The highest percent of amination obtained was about 71% and the amine content increase with the rise in MEA concentration. The CO2 adsorption capacity increase with MEA concentration with the highest capacity recorded was1.63 mmol/g with pure CO2 gas at 30 bars and room temperature.

Radiation induced technique was employed during the synthesis of silver nanoparticles (AgNPs) on pullulan. In this study, the Ag-NPs on pullulan by γ irradiated process is performed to reduce Ag+ ions at the ambient temperature without using excessive reducing agents or producing unwanted by-products of the reductant. Moreover, reducing agent can be uniformly distributed in the solution and AgNPs are produced in highly pure and stable form. The results from ultraviolet-visible spectroscopy (UV-vis) and XRD demonstrated that the silver nanoparticles can be synthesize using pullulan. This can be confirmed by absorption band of UV-vis spectrum at 420 nm as well as the XRD pattern at (1 1 1), (2 0 0), (2 2 0), and (3 1 1) planes of silver. In addition, the pullulan also acts as a reducing and stabilizing agent. TEM images showed formed AgNPs are spherical in shape with smooth edges. The TEM also revealed that the increasing radiation dose decreases the particle size and increase the rate of reduction. It was found that the mean diameter of silver nanoparticles was about 3.98 -14.87 nm. In addition, the size of the AgNPs is believed can be tuned by controlling the radiation doses. The γ-rays doses also provide the powerful reduction process in a harmless condition by producing a very stable silver nanoparticles.

Biocomposite has been widely used as plastics replacement for its biodegradability. However, the water absorptivity defeats its purpose as food packaging. The water absorption analysis for pineapple peel fiber (PAPF) was done according to ASTM D570-98 and it has been proven that the water content increases to 7.2% with the 50% content of PAPF in the bio-composite (50% PAPF). For that matter, hydrophobic coating was synthesized and applied on PAPF based bio-composite. The bio-composite was produced using Low Density Polyethylene (LDPE), pineapple peel fibre (PAPF), Linear LDPE grafted maleic anhydride (LLDPE-g-MA) as compatibilizer and Refined, Bleached Deodorized Olein (RBDOL) as plasticizer. The coating was synthesized by using polydimethylsiloxane (PDMS) and decamethylcyclopentasiloxane as hydrophobic component, silica nano-particles as nanostructured particles and non-organic solvent and non-ionic surfactant p-octyl polyethylene glycol phenyl ether as surfactant. The emulsion was homogenized and after that sprayed onto the surface of PAPF bio-composite and dried in the oven at 50-60˚C for 24 hours. Through the 100µm magnification using field emission scanning electron microscope (FESEM), the hydrophobic coating was proven to conform the Cassie-Baxter hydrophobic property. C-O bond from the PAPF disintegrates after the production of bio-composite from the Attenuated Total Reflectance Fourier Transform Infrared (ATR FTIR) spectrometry transmittance. The application of the coating onto the surface of PAPF bio-composite gave the surface hydrophobic property where the contact angle changes from 82.27±2.66˚ which is hydrophilic to 122.63±2.17˚ which is hydrophobic. The bio-composite with the highest PAPF content will also exhibit self-cleaning ability which makes it suitable for the usage of hydrophobic food packaging material.