► A simple and easy nanoprecipitation method was successfully used to synthesize starch nanoparticles with controllable sizes. ► The shape and size of the starch nanoparticles can be controlled by ...the synthesis parameters. ► Starch nanoparticles with mean particles size of 150nm were obtained in the presence of surfactants during precipitation.
Starch nanoparticles of particle size range between 300nm and 400nm were synthesized by a simple nanoprecipitation method from native sago starch (Metroxylon sagu). Starch nanoparticles were formed by controlled precipitation through drop-wise addition of dissolved native starch solution to excess absolute ethanol. The size and shape of starch nanoparticles were modulated varying the synthesis parameters including the use of appropriate surfactant. Starch nanoparticles with mean diameter of about 150nm were obtained in the presence of surfactants during precipitation. Both solvent and non-solvent systems used in the synthesis method were aqueous-based and the method was facile, and easy to perform as compared to other synthesis approaches previously reported.
Cellulose hydrogel derived from cellulose fibers extracted from printed paper waste is prepared. The hydrogel derived from 3 wt% of the cellulose concentration exhibits a maximum water absorption ...capacity of 465.5%. The effects of the cellulose hydrogel on the soil moisture are evaluated using four types of soils namely river sand, clayey soil, loamy soil, and gley soil (the wetland soil). The potential application of cellulose‐based hydrogel as an eco‐friendly seed germination media of the paddy seeds under the soil‐less condition is evaluated. This study shows that paddy seeds exhibit a higher seed germination rate of 53% when cellulose hydrogel is used as a seed germination media as compared to seed germination rate ranging from 14% to 35% when various types of soil are used as the germination media. The prepared cellulose hydrogel could be applied as an eco‐friendly and cost‐effective seed germination media to enhance the paddy seeds' germination rate.
Cellulose hydrogel is prepared from cellulose fibers isolated from printed paper waste. Cellulose hydrogel is shown to enhance paddy seeds' germination rates.
Solvothermal synthesis has shown to have a great potential to synthesize Zinc Oxide nanoparticles (ZnO NPs) with less than 10 nm size. In this study, we present a rapid synthesis of ZnO NPs in which ...ZnO NPs with more uniform shape and highly dispersed were synthesized using zinc acetate dihydrate (Zn(CH3COO)2 2H2O) and potassium hydroxide (KOH) as a precursor and absolute ethanol as solvent via solvothermal method. Few techniques were exploited to characterize synthesized ZnO NPs including X-ray diffraction (XRD), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET), energy-dispersive X-ray spectroscopy (EDX), fourier transform infrared (FT-IR) spectroscopy, and ultraviolet visible (UV-Vis) spectroscopy. Synthesized ZnO NPs that were prepared via solvothermal synthesis method at 60 °C for 3 hours exhibited a wurtzite structure with a crystalline size of 10.08 nm and particle size of 7.4 ± 1.2 nm. The UV-vis absorption spectrum has shown peak at 357 nm indicate the presence of ZnO NPs. Hence, better quality with uniform size ZnO NPs can be easily synthesized with reduced amount of time via solvothermal synthesis method rather than using other complicated and lengthy synthesis methods.
The effect of urea-loaded cellulose hydrogel, a controlled-release fertilizer (CRF) on growth and yield of upland rice were investigated in upland rice. As with the initial research, nitrogen (N) ...treatments were applied as CRF treatments; T2H (30 kg N ha
), T3H (60 kg N ha
), T4H (90 kg N ha
), T5H (120 kg N ha
) and recommended dose of fertilizer (RDF) at 120 kg N ha
RDF (T6U) in split application and T1 (0 N) as control. Results from this study indicated that applying CRF at the optimum N rate, T4H resulted in maximum grain yield, increasing by 71%. The analysis of yield components revealed that higher grain yield in T4H CRF was associated with an increase in panicle number and number of grains per panicle. Maximum grain N uptake of 0.25 g kg
was also observed in T4H CRF. In addition, T4H CRF recorded the highest harvest index (HI) and N harvest index (NHI) of 45.5% and 67.9%, respectively. Application of T4H CRF also recorded the highest N use efficiency (NUE) and N agronomic efficiency (NAE), 52.6% and 12.8 kg kg
, respectively. Observations show that CRF with only 75% N applied (T4H) in soil improved grain yield when compared to CRF with 100% N and 100% RDF in farmers' conventional split application. This suggested that CRF with a moderate N application might produce the highest potential yield and improved N efficiencies while enhancing crop production and further increase in N supply did not increase yield and N efficiencies. The results suggest that the application of T4H CRF for upland rice would enhance HI, N efficiencies and improve the yield of upland rice. Also, all growth parameters and yield were positively influenced by the application of CRF as a basal dose compared to split application of conventional urea fertilizers.
•Lignin and iodo-lignin nanoparticles were synthesized via the nanoprecipitation method.•Both lignin and iodo-lignin nanoparticles demonstrated excellent antifungal properties.•Lignin and iodo-lignin ...nanoparticles are potential eco-friendly nanoparticle-based antifungal agents.
In this study, lignin (LNPs) and iodo-lignin nanoparticles (ILNPs) with mean particle sizes of 215 nm and 360 nm were synthesized by a nanoprecipitation method. Both LNPs and ILNPs exhibited excellent antifungal efficacy against various fungi such as Cunninghamella sp., Fusarium equiseti, Penicillium chermesinum, Aspergillus flavus, Aspergillus niger and Trichoderma piluliferum. LNPs demonstrated an inhibition effect ranging from 25.81% to 65.29% whereas ILNPs exhibited a superior inhibition effect ranging from 81.34% to 95.57%. This work has proven that both LNPs and ILNPs are promising eco-friendly nano-fungicides for plant pathogenic fungi.
•Alginate nanoparticles was synthesised via ultrasonic-assisted nanoprecipitation.•Alginate nanoparticles was converted to carbon nanoparticles via acid dehydration.•Carbon nanoparticles formed were ...fluorescent.•Carbon nanoparticles were used as optical sensing probe for ferric ions.
Carbon nanoparticles have emerged as a promising alternative to the well-known quantum dots in many biological applications due to their excellent optical properties and biocompatibility. It has received considerable attentions from researchers especially in the aspects of producing these carbon nanomaterials via easier and cheaper synthetic routes. On this motivation, we hereby report an economical and facile synthesis of carbon nanoparticles from alginate via a simple two-step procedure; nano-precipitation through ultrasonication followed by thermal acid carbonisation. Nano-precipitation was first performed on the alginate stock solution to produce nanoparticles with controlled morphology. Precipitation was performed in acidic solution that has coagulated the alginate chains into nanoparticles. Ultrasonic treatment was found crucial to assist the formation of nanoparticles that were more homogenous in the size distribution at around 100nm. The shape was also more spherical as compared to those without ultrasonic treatment. In the carbonisation step, thermal dehydration was employed using concentrated sulphuric acid that has successfully converted the preformed alginate nanoparticles into carbon nanoparticles. The carbon nanoparticles isolated showed high fluorescence even without further surface passivation. The fluorescence of these carbon nanoparticles were utilised for sensitive and selective sensing of ferric ions and it was evaluated to have a linear analytical dynamic range up to 25μM with a limit of detection (LOD) as low as 1.06μM. The system was successfully employed to detect ferric ions in real water sample.
•Cellulose depolymerization using an ionic liquid as solvent and a solid catalyst.•Cellulose depolymerizes via a second order reaction under optimized conditions.•Optimized depolymerization enables ...precise control of cello-oligomer chain lengths.
Cellulose extracted from printed paper wastes were selectively depolymerized under controlled conditions into cello-oligomers of controllable chain lengths via dissolution in an ionic liquid, 1-allyl-3-methylimidazolium chloride (AMIMCl), and in the presence of an acid catalyst, Amberlyst 15DRY. The depolymerization process was optimized against reaction temperature, concentration of acid catalyst, and reaction time. Despite rapid initial depolymerization process, the rate of cellulose depolymerization slowed down gradually upon prolonged reaction time, with 75.0wt% yield of regenerated cello-oligomers (mean Viscosimetric Degree of Polymerization value of 81) obtained after 40min. The depolymerization of cellulose fibers at 80°C appeared to proceed via a second-order kinetic reaction with respect to the catalyst concentration of 0.23mmol H3O+. As such, the cellulose depolymerization process could afford some degree of control on the degree of polymerization or chain lengths of cello-oligomers formed.
Highly porous cellulose beads of controllable sizes were successfully prepared from regenerated cellulose of printed paper wastes based on a facile dissolution and controlled precipitation approach. ...Pure and dispersed cellulose fibers were isolated from finely ground paper wastes by undergoing initial pretreatment and maceration processes in sodium hydroxide solution (NaOH, 12wt%). Dispersed cellulose fibers were subsequently dissolved in an ionic liquid (1-allyl-3-methylimidozoium chloride, AMIMCl) to form a homogenous cellulose solution. Highly porous cellulose beads of controllable sizes within the range of 0.4–2.2mm in diameter were prepared by precipitation in a coagulation bath of ultrapure water under controlled conditions. Cellulose beads of various mean sizes exhibited substantially different specific surface area which ranged between 107m2/g and 498m2/g. Cellulose beads of biocompatibility, high porosity and specific surface area are therefore potentially useful as drug delivery carriers.
•Highly porous cellulose beads derived from printed paper wastes.•Mean diameters of cellulose beads are modulated via synthesis conditions.•Specific surface area inversely proportional to mean diameter of cellulose beads.
Spherically shaped cellulose nanoparticles with average particle diameter range between 70 and 365 nm were fabricated from cotton fibers by a simple nanoprecipitation method. The average particle ...diameter of cellulose nanoparticles could be precisely controlled by modulating the synthesis conditions such as cellulose solution concentration and volume ratio of solvent/non-solvent. Methylene blue (MB) as a model hydrophilic drug was loaded onto cellulose nanoparticles via the in-situ nanoprecipitation process. The loading efficiency and release profile of MB were observed to be affected by the average particle diameter of cellulose nanoparticles.
(a) SEM image of cellulose fibers facial cotton and (b) TEM micrograph of cellulose nanoparticles prepared from 0.01 w/v % of cellulose solution. Display omitted
In this study, an eco-friendly controlled release fertilizer cellulose-based hydrogel was prepared from cellulose fibers derived from wastepaper, epichlorohydrin (ECH) as a crosslinker and carboxy ...methyl cellulose (CMC) as a gelling agent. A maximum swelling capacity of 2000% was achieved for cellulose hydrogel with optimum composition. The soil moisture contents in the presence of optimized cellulose hydrogels were determined using the digital moisture meter. Maximum soil moisture of 36.5% was obtained in topsoil, followed by 30.1% in wet clayey soil and 23.4% in sandy soil after 7 days. Urea as a model fertilizer was loaded onto the cellulose hydrogels to control the release of fertilizer. The maximum loading capacity of urea in cellulose hydrogel is 0.51 g/g. The urea-controlled release profiles of the cellulose hydrogel in distilled water and various types of soils were investigated. The formulation of cellulose hydrogels was observed to facilitate the gradual release of urea, with about 74.71% release in topsoil, 73.37% release in wet clayey soil and 71.84% release in sandy soil within 42 days when compared to the free urea which was about 97.32%, 95.09% and 98.47% release in topsoil, wet clayey soils and sandy soils, respectively within 7 days. The result of this study shows that the urea-loaded cellulose hydrogel could be a promising controlled-release fertilizer.
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