Introduction
The most positive feature of nanotechnology is the anomalous properties including soft magnetic nature and magnetic nanoparticles at various compositions.1, 2 They contribute typical applications in different technological and fundamental research areas such as bio-medical, and bio-processing and are used as a good catalyst among many other NPs.3, 4, 5 Among the spinel ferrite compounds zinc ferrite exhibits superparamagnetic behaviour and prospective applications in many fields including photocatalysis, Magnetic Resonance Imaging (MRI), Li-Iron batteries and gas sensors. Various synthesis methods are proposed to prepare ZnFe2O4 nanoparticles such as the coprecipitation method, thermal decomposition, solvothermal, hydrothermal and ball milling. In this work superparamagnetic ZnFe2O4 NPs were synthesized by adopting the method of Co-precipitation method. Polyethylene glycol act as a capping element for the synthesis.6, 7, 8 The most auspicious feature of nanotechnology is the magnetic nano parties of different compositions. Since they have applications in the biomedical field and have catalytic properties, it is significant to get further detailing about Zn ferrite nanoparticles and to enhance the application level or develop new one’s careful studies based on their functional sample size and also along with that their antifungal behaviour is essential. Among the spiral ferrite compounds, zinc ferrite exhibits superparamagnetic behaviour and it has prospective applications in many fields. Such as photocatalysis, magnetic reasonable imaging, Lithium — ion batteries and gas sensors.9, 10
In the present paper, to characteristics structure and morphology of nanoparticles by using XRD, FTIR, U. V visible spectroscopy. To assess the properties of synthesized nanoparticles by antifungal using the Agar-well diffusion method.
Synthesis
Zinc ferrite nanoparticles is prepared as follows
Here we use one mol of ferric nitrate, one mol of zinc nitrate, 0.1 mol of polyethylene glycol (PEG), one mol of sodium hydroxide (NaOH), one mol of ammonium carbonate, Ferric nitrate and zinc nitrate are taken in a clean burette and the aluminium nitrate is taken in a clean pipette, while the rest of others are mixed well in a beaker and is subjected to magnetic stirring where all these get stirred well. Allow the solution from the burette to fall on the solution drop by drop and the colour of the solution begins to change. Once the stirring is over, the solution is removed from to test tubes and centrifugation is performed at a rate of 4000rpm for 15 minutes then settled precipitate is washed and separated from the test tubes. After that, it is heated to remove its water content and then it is crushed into powder using mortar. The powder is then heated using a muffle furnace at altered temperatures (500, 600 & 700℃) continuous for up to 4 hours to get the required aluminium doped zinc ferrite nanoparticle.
Results
XRD analysis
The crystallographic structure of the obtained ZnFe2O4 nanoparticles was identified by using XRD data. Average particle size, the lattice parameter and X-ray density can be measured.11, 12, 13, 14
Table 1
The values of crystalline size (nm), particle size (nm) in FE-SEM, lattice constant(a), X-ray density, cell volume and specific surface area (S)
Table 2
Thevalues of bond length A-O (Å), bond length B-O (Å), ionic radius rA and ionicradius rB
|
Temperature |
Bond Length in A-O sites (Å) |
Bond Length in B-O sites (Å) |
Ionic radius rA (Å) |
Ionic radius rB (Å) |
|
5000C |
3.66 |
5.2 |
4.98 |
5.714 |
|
6000C |
3.64 |
5.26 |
4.96 |
5.7 |
|
7000C |
3.63 |
5.24 |
4.95 |
5.66 |
All the samples show diffraction peaks at (311) compared with the JCPDS card No: 82-1049, which confirms the synthesized product single-phase cubic in synthesized nanoparticles. The crystallite size can be measured using the shearer’s equation. From Table 1 we observe that when temperature increases the crystallite size and particle size also increase while the lattice parameter decreases. The X-ray density increases with the increasing temperatures from 500℃ to 700℃.
FE-SEM analysis
The FESEM images exhibit agglomerated branches of spherical shaped nanoparticles, because of their high surface energy. The FESEM images show that thus agglomeration of zinc ferrite nanoparticles because of the effect of the capping agent on modifying crystal size.15, 16, 17
FTIR analysis
All samples exhibited peaks near 530cm-1corresponding to the Fe-O stretching frequency near 425cm-1 peaks indicated zinc ferrites nanoparticle. The present study suggests a linear variation between crystallite size and temperatures. This observation from the FTIR study strongly supports the result observed by XRD values. All samples have absorption bands in the region of 500-550 cm-1 and 400-450 cm-1. The high-frequency band is due to the stretching vibration of the unit cell in the tetrahedral A sites and the lower is due to the metal-oxygen in the octahedral B site i.e., high- the frequency band is due to the Zn-O stretching and the lower frequency corresponds to Fe-O stretching which confirms the formation of ZnFe2O4 nanoparticles. From the spectrum, some other absorption bands are also observed in the range 3750-3000 cm-1, 1750-1500 cm-1 and 1500-1250 cm-1 representing stretching frequencies of N-H bond and C=O and also O-H stretching vibrations respectively. As the temperature increases the bonds other than Zn-O, Fe-O and O-H bonds disappear. The appearance of the O-H bond indicates the presence of water in the sample.12, 13, 14, 15
U-V analysis
The change in characteristic properties of the synthesized sample towards the effect of light was investigated by UV-Visible spectral data. Figure 4 shows the spectra in the sample range of wavelength 200-800 nm. Band gap energy obtained for ZnFe2O4 is reducing with an increase in temperature.
Anti-fungal analysis agar-well diffusion method
The Biological activity and antifungal ability of samples were estimated by conducting Agar well diffusion technique. For that purpose, the analysing samples have purposefully interacted with test organisms that are seeded in a test plate.16, 17 The results were obtained in the form of a circular zone of inhibition. The results were evaluated according to the diameter of the zone. The test plates were kept overnight for the growth of species. Aspergillus Niger was considered as a standard for the analysis. Wells of nearly 10 mm was used and samples of varying concentration such as 25µg/mL and 1000µg/ mL were added to these wells. The circular zone of inhibition was estimated after incubation at room temperature overnight and compared with that of the standard. From the antifungal activity of the prepared samples, it was found that they are active against the fungal pathogen Aspergillus Niger except at 700℃. We can conclude as the temperature increases the zone of inhibition reduces and at 700℃ it will inactive.
Table 3
The antifungalactivity of zinc ferrite nanoparticles at different concentration 250µg/ml, 500µg/ml, 1000µg/ml at 5000C
|
Sample |
Concentration (µg/ml) |
Zone of exhibition (mm) |
|
5000C |
250 |
Nil |
|
500 |
12 |
|
|
1000 |
14 |
|
|
Clotrimazole |
100 |
21 |
Table 4
The antifungalactivity of zinc ferrite nanoparticles at different concentration 250µg/ml, 500µg/ml, 1000µg/ml at 6000C
|
Sample |
Concentration (µg/ml) |
Zone of exhibition (mm) |
|
6000C |
250 |
Nil |
|
500 |
12 |
|
|
1000 |
14 |
|
|
Clotrimazole |
100 |
26 |
Conclusion
Zinc ferrite nanoparticles were successfully prepared by the coprecipitation method using PEG as a capping agent. The XRD confirms the crystal structure and phase purity of the sample. The FESEM of ZnFe2O4 nanoparticles shows the spherical agglomerated particles’ antifungal activity showed the application of zinc ferrite NPs in inflammation and cancer therapy. FTIR study confirmed the presence of zinc ferrite NPs at all annealing temperatures. The optical study uses UV visible spectroscopy and can notice with the increase in temperature the bandgap energy decreases. From the antifungal activity of the prepared samples, it was found that they are active against the fungal pathogen Aspergillus Niger except at 700℃.
