Impact of (nano)formulations on the distribution and wash-off of copper pesticides and fertilisers applied on citrus leaves

2019 ◽  
Vol 16 (6) ◽  
pp. 401 ◽  
Author(s):  
Melanie Kah ◽  
Divina Navarro ◽  
Rai S. Kookana ◽  
Jason K. Kirby ◽  
Swadeshmukul Santra ◽  
...  

Environmental contextThere are great concerns around current wide usage of copper-based agrochemicals. We compare the fate of nano- and conventional forms of copper, in particular their resistance to wash-off by rain (rainfastness), following their application to citrus leaves. Results showing large differences between the formulations in the amount and forms of copper washed from the leaves provide essential information to optimise agrochemical efficacy while minimising the environmental impact. AbstractThis study compares the rainfastness of nine forms of Cu, including nano and conventional Cu-based fungicide formulations, as well as their salt or bulk equivalents. Rainfastness is the ability to resist wash-off; it is a key property for improving pesticide formulations and for assessing the potential transfer of pesticides to the soil. A new protocol was developed to characterise losses of Cu from treated leaves. It consisted of dipping the leaves in rainwater and then in an acid/ethanol mixture followed by size fractionation. The proportion of Cu lost by wash-off from citrus leaves ranged from <2% (Tribasic, nCuO or Cu(OH)2) up to 93% (CuSO4) of the initial amount of Cu applied. Intermediate Cu losses were observed for formulations with silica (nano)particles (9–14% of applied Cu), Kocide (22%), ChampDP (31%), and a formulation with graphene oxide (47%). Smaller particles generally resulted in less wash-off, possibly due to stronger attachment to the leaf surface, but other factors such as the particle shape and solubility also played an essential role. The retention of nCuO to the leaves was particularly high, and the exact mechanisms involved (e.g. foliar uptake) deserve further work. Most of the Cu was washed off in its ionic form (>74%). Two Cu formulations (one commercial formulation and the formulation with graphene oxide) also showed wash off in significant proportions of Cu (~17%) in the nano-sized fraction. This study provides essential information on the amounts and forms of Cu that may reach the soil after the application of Cu-based agrochemicals. The great diversity in behaviour across the range of formulations considered highlights the need for more systematic research to fully exploit the potential improvements of current agrochemicals through (nano)formulation technologies.

2019 ◽  
Vol 9 (01) ◽  
pp. 58-64
Author(s):  
Senthilnathan B ◽  
Billy Graham R ◽  
Chaarmila Sherin C ◽  
Vivekanandan K ◽  
Bhavya E

Objective: Drug targeting is the capacity of the dosage form. In which the therapeutic agent acts specifically to desired site of action in the non-targeted tissue with the help of Nano particles is called as the drug targeting. IMATINIB is a used to treat cancer by chemo therapy. Cancers like chronic myeloid leukemia cancer (CML) and acute lymphoblastic leukemia cancer (ALL) and other specific types of gastrointestinal stromal cell tumor (GIST) systemic mast cell disease and Bone marrow failure disorder. It is administered by oral root. For ATP, Tyrosine kinase is act as a binding site. Methodology: The drug IMATINIB is loaded in the polymer chitosan, poly-(D) glucosamine is a bio compactible, bio degradable, nontoxic, antimicrobial and soluble in solvents. This preparation is done by emulsion-droplet coalescence method. Content of the Drug, Size of the particle and Zeta potential, Encapsulation efficiency and Drug release testing are described for this formulation in this study. Results: The Imatinib Nano particles were formulated and evaluated for its invitro drug release profile. Based on the invitro drug release profile of Imatinib nano particles formulation (INP1 – INP5) formulation INP3 was selected as the best formulation in which the particle size was 285.9nm. The invitro % drug release of INP3 formulation was 99.76 ± 0.82 and it was found to be the suitable formulation to manage the cancer. Conclusion: Hence it is concluded that the newly formulated controlled release nanoparticle drug delivery system of Imatinib may be idol and effective by allowing the drug to release continuously for 24 hrs.


2015 ◽  
Vol 51 (18) ◽  
pp. 3824-3827 ◽  
Author(s):  
Fei Zheng ◽  
Wei-Long Xu ◽  
Han-Dong Jin ◽  
Meng-Qi Zhu ◽  
Wei-Hao Yuan ◽  
...  

It is demonstrated that oxidative debris can be separated and largely removed during the surfactant assisted phase transfer of graphene oxide from a water/ethanol mixture to dichlorobenzene.


2021 ◽  
Vol 130 (24) ◽  
pp. 244901
Author(s):  
Ting Lu ◽  
Senyu Yang ◽  
Bingqi Zhang ◽  
Xinlei Li ◽  
Tongsheng Chen

2020 ◽  
Vol 28 ◽  
pp. 101204 ◽  
Author(s):  
A.E. Kabeel ◽  
Ravishankar Sathyamurthy ◽  
A. Muthu Manokar ◽  
Swellam W. Sharshir ◽  
F.A. Essa ◽  
...  

2020 ◽  
Vol 8 (38) ◽  
pp. 20111-20121
Author(s):  
Yinze Zuo ◽  
Yuejin Zhu ◽  
Qi Wang ◽  
Kezhong Lv ◽  
Weiming Su ◽  
...  

A novel strategy for suppressing the “shuttle effect” of LiPSs and facilitating reaction kinetics is achieved using the reduced graphene oxide (rGO) with incorporated polar LiNiPO4 (LNPO) nano-particles as functional coating layer for separator.


Author(s):  
Imad H. Khaleel ◽  
Abdulkareem A. Alkhafaji ◽  
Hussein A. Miran ◽  
Zainab N. Jaf

In this research, a novel thin film Si-GO10 and nano-powders Si-GO30 of silica-graphene oxide composite were prepared via sol-gel method and deposited on glass substrates using spray pyrolysis. XRD results showed a relatively strong peak in graphite layer that corresponds to the plane of (002). TEM images displayed that SiO<sub>2</sub> nano-particles were randomly distributed on the surface of Si-GO30 sample, and the particle size in these nano-powders was below 50 nm. Moreover, silica nano-particles on the surface of GO plates exhibited almost a spherical and rod-like nanoparticles shapes, which in turn confirmed the formation of SiO<sub>2</sub>-GO nano-hybrids. FESEM analysis reveals a different morphology, the Si-GO10 sample is so rough and crumble, while the Si-GO30 sample is relatively smooth on the surface. Photocatalytic investigations revealed the composite materials exhibit high activity for dye adsorption and decomposition. Si-GO10 thin film did not undergo degradation after 120 minutes, however, for Si-GO30 nano-powder, the adsorption peak intensity was reduced to 665 nm, indicating a decrease in the dye concentration in the solution. FTIR analysis demonstrated that carboxylic functional groups are decreased by increasing silica particles. Photo-Luminescence (PL) spectrum in Si-GO10 thin film disclosed a severe emission peak at about 675 nm. This spectrum was completely disappeared in Si-GO30 nano-powders. Results of the antibacterial properties emphasized that Si-GO30 nano-particle would prevent Escherichia. coli growth after 20 hours. The presented methodology allows for the synthesis of graphene oxide supported silicon dioxide nano-particles for promising applications in photocatalytic and antibacterial fields.


2021 ◽  
Vol 13 (3) ◽  
pp. 473-480
Author(s):  
Yihan Jin ◽  
Xi Luo ◽  
Jinglin Zhang ◽  
Dongliang Zhao ◽  
Kewei Gao

Micro-emulsion method is adopted to synthesis rGO-Fe3O4-PANI (reduced graphene oxide-Fe3O4-polyaniline) ternary nano-composites. With the different contents of aniline (0.1 g, 0.2 g, 0.3 g) added in production, the corresponding final products are named as sample 1, sample 2, sample 3, respectively. The results of TEM indicate that the mean size of Fe3O4 nano-particles is 14 nm and they are anchored onto rGO slice. There are some PANI polymer wrinkles distributed on the rGO surface uniformly. The electro-magnetic data demonstrate that sample 1 possess a great enhancement of the electro-magnetic wave absorption abilities and frequency bandwidth among the three samples. The RLmin (minimum reflection loss) value of sample 1 is -44.16 dB at 4.29 GHz with 5 mm coating thickness and 1.77 GHz (3.72-4.94 GHz, 13.33-13.88 GHz) frequency bandwidth (RL <italic/> -10 dB). We can believe that this kind of nano-composites will have a promising application in the future.


2021 ◽  
Vol 13 (3) ◽  
pp. 447-454
Author(s):  
Yihan Jin ◽  
Xi Luo ◽  
Jinglin Zhang ◽  
Yipeng Yu ◽  
Jing An ◽  
...  

Chemical coprecipitation method, hydrothermal method and micro-emulsion method were adopted to prepare pure Fe3O4 (X1) magnetic nano-particles, reduced graphene oxide-Fe3O4 (X2) binary composites and reduced graphene oxide-Fe3O4-polyaniline (X3) ternary composites. The morphology, structure and magnetic performance were characterized by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM) and vibration sample magnetism (VSM). The result of TEM showed that Fe3O4 nano-particles distributed uniformly on the surface of graphene and PANI matrix and the mean size was bout 13~14 nm. The electromagnetic data was tested by vector network analyzer demonstrating that the minnimum reflection loss (RLmin) value of X3 was -53.94 dB at 16.1 GHz with 1.5 mm thickness and 3.82 GHz (14.18~18 GHz) absorbing bandwidth (RL<italic/>-10 dB). Compared with pure magnetic Fe3O4 powders and rGO-Fe3O4 binary composites, the rGO-Fe3O4-PANI ternary composites were conduced to a great reinforce of the electro-magnetic wave absorbing properties and absorbing bandwidth.


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