Fabrication of copper sulfide nanoparticles from b oswellia ovalifoliolata leaf extract and their potential application of environmental pollutants removal, antibacterial activity and antioxidant activity

. A nanomaterial has played a major role in protecting the environment-related issues. The prime reason for that nanomaterials synthetics approach is greener pathway, without using any hazardous chemicals and solvents. A huge number of plant-mediated metal sulfide nanoparticle (especially, Copper sulfide) synthesis has been reported and is still successfully continuing, because of its cost effective manner, eco-friendly nature, simple approach, reaction was carried out room temperatur. The current reports to synthesis of Copper sulfide nanostuctured materials through the green patch way, using Boswellia Ovalifoliolata leaves extract. From the UV-Visible spectroscopy noticed nanoparticles absorbance value is around 325 nm. As identified by FT-IR spectroscopy, a variety sources of phytochemicals in the extract which are responsible for the reduction of metal ions and stabilizing of the nanoparticles. X-ray diffraction studies revealed that nanomaterials were crystalline in nature, average crystalline size around 11 nm. SEM revealed that nanoparticles are spherical in nature and average size is 38.43 nm. The current report emphasizes that the materials are an excellent catalyst activity for the reduction of environmental pollutant azo dyes, antibacterial and antioxidant activity. The current article highlights the reduction of the azo dyes, antibacterial and antioxidant activity so the nanomaterials are apromising for the reduction of polluntat dyes.


Introduction
Nanotechnology is considered to be most exiting research in various fields such as environment, medicine, food technologhy, material science due to the fact that the material having wide variety of properties.There are several types of nanoparticles like metal and metal Oxide NPs, metal composite and metal sulphide nanoparticles which are synthesised through green synthesis and also through chemical methods.They have many applications in various fields.Nanoscience is the combination of nanotechnology and chemistry."Nanoscience" is the emerging science of objects which is indicated to intermediate in size between the largest molecules and the smallest molecules that can be synthesized by current photolithography; which is represents, the science of objects with a smallest dimensions ranging from one nm to 100 nm [1].Nanotechnology deals with the study of nanoparticles in varying of size from nanometers [2].
The synthesis of metal sulphide nanoparticles has great interest in the field of nanotechnology.The synthesis of noble metal sulphide nanoparticles has a growing attention due to their new method of development of nanoparticles using green methods, chemical methods and physical methods and also morphological and characteristical changes.Nanoscience is the emerging trends of research work.Nanometre-sized particles have novel properties which were used in different applications such as optical, electronic and structural properties [3,4].Nanoparticles can be obtained from varous methods like top-down and bottom-up method.However, from the top-down method involves breaking of a bigger molecules into a an smelllest atom whereas, in the case of bottom-up aprouch making a molecule from an atom.Some of the nanoparticles are it has high specific surface area due to its small characteristic dimension.Surface effects play an increasing role, sometimes decisive role.The energy of surface atoms is higher than the atom in the bulk solution hence the chemical reactivity was different.Biological samples like cells react with the nanoparticles differently from the bulk sample [5] The metal sulphide nanoparticles were formed by the reaction of metal acetate or metal nitrate with the sodium sulphide.Sulphide is an inorganic anion of Sulphur with the chemical formula S ─2 .It contributes no colour to the Sulphur salts.As it is classified as a strong base, even dilute solution salts such as Na2S are corrosive and can attack the skin.The sulphide anion can assimilate a proton by recombination.Na2S is an important industrial chemical, were it used in manufacture of Kraft papers, dyes, leather tannings, crude petroleum processing treatment of heavy metal pollution, and also in preparation of metal sulphide nanoparticles [6].
The nanoparticles has different form as metal oxide nanoparticles, metal sulphide nanoparticles etc. Hence green synthesis of metal sulphide nanoparticles has various applications in it.Many of the recent researchers have synthesizing the nanoparticles in various methods.It has a variety of properties like optical, electrical, magnetic and chemical properties [7].
Nanoparticles are synthesised by green methods from Boswellia Ovalifoliolata leaf extract.It was found in Tirumala hills of Andhra Pradesh and also in Seshachalam hills of Eastern Ghats of India.B. Ovalifoliolata is a medicinal tree and hence its stem, bark, leaves etc., are also used for medicinal purposes.The vernacular name of B. Ovalifoliolata was Konda Sambrani, Adavi Sambrani, and Guggilam.The tribes in those areas were using this plants leaves, stem, bark, etc for medicinal purposes [8].Only Silver and Zinc Oxide nanoparticles were synthesized from the B. Ovalifoliolata no other nanoparticle were synthesized from this plant [9,10].Hence, CuS NPs were synthesized by using this plant to study the antibacterial activity and photocatalytic activity.
The green synthesis of the nanoparticles is based on the presence of plant materials.Plant materials were used to reduce the metals from M + X to M 0 .The reduction of metals from +X state to 0 states involves the capping of the phyto-chemicals on the NPs.Hence the presence of phyto-chemicals play key role in the formation of metal sulfide nanoparticles [11].
Nowadays it is important to synthesis the nanoparticles in eco-friendly manner and through the low cost process [12,13].If the synthesized nanoparticles are environmental friendly then it can be preferred for medicinal applications as well.Nanoparticles can be used for drug designing, drug formulation, etc., mainly nanoparticles can be used for the treatment of cancer.Using nanoparticles we can do the photo-thermal ablation studies to study the cancer cells in our human body [14].
Synthesis of nanoparticles can be broadly classified into two methods that are top-down, bottom up method.Top-down methods breaks the bulk material into nanoscale with various lithographic techniques such as grinding, milling, etc., bottom up process making a groth of an atom to a nanosize formation [15].Nanoparticles can also be fabricated from chemical, physical, biological methods, microwave irradation, vapour condasation, sol gel, electrochemical techniques, evaporation-condensation, photo-chemical irradation, laser ablation, electron irradiation, thermal deposition, combusion method, gamma irradiation, micro emulsion, methods, metal and non-metal salts reduction by green organic, inorganic substance and plant extract as a reducing agents [16].Now-a-days an interest of synthesizing nanoparticles is through biological methods using bacteria, fungi, algae, and also from plant materials [17].
The nanoparticles have various applications in different fields in which metal sulphide has several applications in it.The fields in which the nanoparticles were used most was like photodynamic therapy, photothermal ablation studies, photoacoustic, cytotoxic, anticancer activity, antimicrobial, antifungal, antioxidant, antibacterial, photo-degradation drug delivery, sensors, water treatment, antioxidant activity, pollutant dyes degradation [18][19][20] Water purification by Treatment of Metal sulfide nanoparticles was studied in the previous reports with the help of photo reactor, solar system, sunlight irradiation and other inter energy treatment process, however still need to develop a advance techniques are required to complete the environmental issues.Dyes have been used extensively in the industries like paint, paper industries and leather, textile industries, food, laboratory, colouring agent.The large scale amount of dyes realised directly into the environment by products and this may cause very seviour problems to living creatures.A dye is very harmful to environment which affects our water bodies; soil and air etc., to reduce the potential hazardous effects on humans; NPs can be used to reduce such effects on environment [21].In a simpler manner to developed metal sulfide nanoparticles used to treatment of water purification.However, Copper sulfide nanomaterials have been studied significantly to removal of pollutant dye degradation by photocatalytic activity method, reduction process, and solar irradiation method [22].
Copper Sulfide nanomaterials were confirmed through UV-Visible spectrometer by observing the absorbance of the wavelength of the metal sulfide nanomaterials.FT-IR spectroscopy to identify the phytochemicals present in the Boswellia Ovalifoliolata leaves extract and metal sulfide nanomaterials, XRD pattern to study the structure and the size of the nanoparticles, from SEM analysis to confirm the nature of the nanomaterials, size and morphology of the metal sulfide nanopariticles.Succssfully, synthesized metal sulfide nanoparticles to test against the gram positive, gram negative bacteria's study, and DPPH radical mechanism for the antioxidant activity and furthermore, to studied the catalytic activity for the reduction of environmental pollutant azo dyes to protecting the environment-related issues.

Methods and Materials
Copper acetate mono-hydrate, sodium sulphide (Na2S) chemicals were purchased from Sigma Aldrich, India and remaining reagents were used analytical grade.The Congo red, Tartrazine dyes are used for the catalytic activity to test the reduction process and those used dyes also analytical grade.Distilled water was used as a solvent throughout the experiments.

Preparation of leaves extract
The leaves of Boswellia ovalifoliolata was collected and wash with tap water and dried at room temperature then finely make it into fine powder.The Boswellia ovalifoliolata fine powder 3 gm weighed and dissolved in 100 ml of deionised water.This solution mixture was kept on hotplate for 30 mins at 80℃ and then this solution was allowed to cool at room temperature.After that the solution was cooled it and filtered using whatmann no.1 filter paper and finally, the filtrate (extract) was collected and stored at 4 ºc for further preparation of Copper Sulfide nanoparticles.

Phytochemical quantitative analysis
The following tests were performed to identify the presence of phytochemicals in the plant extract.

Test for phenols : Qualitative determination of phenols
The leaf powder was dissolved in 5 ml of distilled water.To that solution few drops of 5% neutral ferric chloride was added.The dark green colour indicates the presence of phenols in the leaf extract.

Quantitative determination of phenols-FC reagent test
The extract was prepared by weighing 0.5 gms of the Boswellia Ovalifoliolata leaf powder which was dissolved in 50 ml of 70% ethanol (35 ml of ethanol in 15 ml of distilled water).This ethanolic extract of 100 µl was added to 2 ml of Folin-Ciocalteu reagent (FC reagent) and then 4 ml of sodium carbonate.The deep blue colour will formed due to the presence of phenols.The absorbance was taken for this solution to calculate the total phenolic content (TPC) in the leaf extract.

Test for flavonoids
The presence of flavonoids in the extract was identified by alkaline test.The extract was added to potassium hydroxide or sodium hydroxide, the solution will become intense yellow colour.When Con.HCl was added to that yellow colour solution the intense yellow colour will disappear.This shows the presence of flavonoids in the extract.

Antibacterial activity
Antibacterial activity of the synthesised Copper Sulfide nanoparticles was tested with the help of two bacteria's namely Staphylococcus aureus which is a gram positive bacteria and Pseudomonas aeruginosa which is gram negative bacteria that were cultured on agar plates added with different concentrations of synthesised Copper Sulfide nanoparticles by well diffusion method.

Catalytic activity of Copper Sulfide nanoparticles
The fabricated of Copper Sulfide nanoparticles was tested for its catalytic activity towards reduction of environment pollutant organic dyes that are Tartrazine dye (TZD), Congo red dye (CRD) at room temperature environment.Therefore, the reduction of pollutant dyes was carried out in the presence of specific amount of NaBH4 and Copper Sulfide nanoparticles was added to the pollutant dye solution for the catalytic reduction of dyes, then finally the complesion of reduction process was monitored by absorbance spectroscopy at each 1 min time intervals at 200 to 800 nm at room temperature.

Characterization techniques
UV-Visible spectrum were analysed to confirm the presence of Copper Sulfide nanoparticles and also to study the band gap of the synthesised Copper Sulfide nanoparticles nanoparticles.The presence of the functional groups was studied using FT-IR spectrometer.XRD is used to study the structure and the size of the synthesised Copper Sulfide nanoparticles.SEM is used to study the morphology, size of the synthesized Copper Sulfide nanoparticles.

UV-Visible analyis of Copper Sulfide nanomaterials
Initial, characterization of the synthesised Copper Sulfide nanoparticles was carriedout with the UV-Visible absorbance spectroscopy that is Jasco V-670 UV-visible double beam spectrophotometer.A 10 fold dilution of the synthesised Copper Sulfide nanoparticles with deionised water was performed to detect the nanoparticles by visible analysis.The synthesized materils were recorded by absorbance spectroscopy and the wavelength range between 200 to 800 nm.

Founcnal groups Analyis from Fourier Transform Infra Red Spectroscopy
Phytochemicals was determind by FT-IR analysis and within the range of 400 cm -1 to 4000 cm -1 using Shimadzu IR AFFINITY-1 using KBr pellets mixed with dried and purified nanoparticles.Using JASCO FT-IR 4100 under diffuse reflectance mode the instrument was operated at a resolution of 4 cm -1 and also did number of scans to identify the functional groups present in the nanoparticles and Boswellia Ovalifoliolata leaves extract.

X-Ray Diffraction Spectroscopy
XRD analysis is used to identify the average crystalline size of the synthesised Copper Sulphide nanoparticles.Bruker D8 Advance diffractometer with Cu Kα radiation (λ=1.54 0 ) was used to identify the diffraction patterns of the samples.After the reaction of the nanoparticles was complete it was centrifuged at 3000 rpm for 15 mins and carefully pellets were collected and grinned to make a fine powder.The obtained fine powder around 50 mg given for the XRD analysis.The sample was scanned at the detector angle range of about 10º-90º with the scanning rate 4º/min and a step size of 0.02º.

Scanning Electron Microscope Analysis (SEM analysis)
The sample for SEM analysis was prepared by dropping small amount of synthesized Copper Sulphide nanoparticles on 1cm by 1 cm glass slide and allows drying for 30 mins under infrared lamp.Then the SEM analysis will give the morphology and the elemental composition of the Copper Sulphide nano-materials.

UV-Visible analysis of Copper Sulfide nanoparticles
The formation of Copper Sulphide nanoparticles were initially confirmed through UV-Visible spectroscopy.The absorbance of the synthesized CuS NPs was found to be 325 nm which was matched with already reported of Copper sulphide nanoparticles [23].Hence the Copper Sulphide nanoparticles were confirmed through the Surface Plasmon Resonance (SPR) band which is responsible for the excitation of the electrons in the NPs and gives the absorbance band.Thus, the formation of Copper Sulphide nanoparticles was confirmed through the SPR band in the UV-Visible Spectroscopy.Fig. 1 represented the characteristic absorption spectroscopy of Copper Sulphide nanoparticles.Scherrer Formula is D = K×λ/β×Cos (θ) Where, β is denoted as a full width-half maximum of peak intensity which is express in radians (FWHM), D is denoted as average crystalline size of the materials, K is represent the Scherrer coefficient and that constst value is 0.891, λ is X-ray wavelength of the light beam which is around 1.5406 A 0 , θ is represent the Bragg's angle that is taken form 2θ. Therfore, the crystalline size of the Copper Sulphide nanoparticles was calculted to be around 11.57 nm [24].

Fourier Transform -Infrared Spectroscopy of Copper Sulfide nanoparticles
From the fourier transform infrared tecnique was used to identify the biomolecules present in the Boswellia Ovalifoliolata leaves extract and synthesized Copper sulfide nanoparticles.Therefore, the identified bio-molecules are responsible for the formation, stabilization of the copper sulfide nanoparticles.Here, identified the noticeable functional groups in the Boswellia Ovalifoliolata leaves extract.The bioactive molecules which were present in the Boswellia Ovalifoliolata leaves extract were responsible for the capping of the Copper Sulfide nanoparticles which are shown in Fig. 3.The peaks at 3344.5 cm -1 , 1705.07 cm -1 , 1604.77cm -1 , 1442.75 cm -1 , 1321.24 cm -1 , 1192.24 cm -1 , corresponds to -OH, -C=O, -NH, -C=C, -CN groups present in the Boswellia Ovalifoliolata leaves extract [25].Whereas Fig. 4 shows the peaks at 2978.09 cm -1 , 1537.27 cm -1 , 1384.89 cm -1 corresponds to -CH stretching, -C=O and -CH3 bending were the groups present in the synthesised Copper Sulfide nanoparticles.The functional groups like -OH, -NH was responsible for the capping on the surface of the synthesized Copper Sulfide nanoparticles.nanoparticles from green methods was subjected to Scanning electron microscope to know the morphology of the NPs.SEM was coupled with Energy Dispersive X-ray diffraction (EDAX) to identify the elemental composition of the Copper Sulfide nanoparticles.The Copper Sulfide nanoparticles were investigated under different magnification powers and the size of the NPs found from SEM analysis was to be around 35-43 nm [26].the average size of the synthesized Copper Sulfide nanoparticles was around about is 38.43 nm.The size of the Copper Sulfide nanoparticles obtained was within the range of the nanoparticles.The structure of the Copper Sulfide nanoparticles was found to be cubic centered hexagonal.The peaks obtained from EDAX indicates the presence of copper and sulphide this proves that the synthesized Copper Sulfide nanoparticles has only copper and sulphide ions.Fig. 5 explains the SEM results and EDAX peak.

Catalytic activity of Copper Sulfide nanoparticles
The pollutant dyes Tartrazine, Congo red dyes are used in food industrial, paper industrial, and textile manufacturing industries.Therefore, water contamination due to verstile uses of dyes in textile, food, leather and paper industries.Those dyes are causes a serious problem on environment.Hence, its nesesarry to remove the pollutants from the enviroment to best way to reductoin of dyes by copper sulfide nanpartiles in the environment wiith a ecofriendly nature.In the simple proces, for that need to maka a test solution and freesh sodiumbodohydride to analysis the catalytic actity of copper sulfide nanpartiles.

Catalytic of Copper Sulfide nanoparticles for the reduction process of towards Tartrazine dye
Tartrazine is a yellow colour, water soluble mono azo group and having sulphur group.However, when ingested, it's reduced to sulfanylic acid.Sulfanylic acid often caused allergic reaction, including urticaria, asthma, blood spots haemorrhages.In the absorbace spectra, the TZD dye is exhibit a noticebale absorption band around 428 nm, therfore, which is indicated to n to π* electron transition.For the reduction process to make a 3 mL test solution (Dye; 1×10 -4 M) molar concentration, 200 µL sodium borohydride (NaBH4, 0.05 M) solution and finally in the presence of catalyst 150 µL of green Copper sulphide nanoparticles (1mg mL-1) was added and the reaction was carried out and recored by UV-Vis absorbance analysis at around 428 nm.Finally, TZD dye was decolourised within 7 min (97.36 %), which is represented in (Fig. 6 A, B).The catalytic efficiency of Copper Sulfide nanoparticles catalysed to reduced Tartrazine dye molecules that efficiecny was estimated by using the equation that is ''the reduction of degrdation efficiency = (A0─At)×100/A0, Where, A0 is the initial concentration of trartrazine dye molecules absorbance values, At is the time took for the reduction of tartrazine dye molecules absorbance values at time ''t" exposure on test solution.Therefore, from the results concluded that the reduction efficiency (%) of tartrazine dye molecules by Copper Sulfide nanoparticles was decolourisation up to 97.36%.In Similar way reported catalytic activity of Tartrazine dye molecules degradation [27].

Catalytic activity of Copper Sulfide nanoparticles for the reduction process of towards Congo red dye
To investigate catalytic activity of copper nanoparticles were, to the 3 mL of dye solution molar concentration (1×10 -4 M), added sodium borohydride (NaBH4, 200 µL), specific amount of green Copper sulfide nanoparticles (150 µL, (1mg mL-1)) then absorbance of reaction mixture was gradually decreased that was noted in the UV-Visible spectrophotometer and also colour intensity changes good evident for the reduction of Congo red dye in a periodically manner which is noted in the absorbance spectroscopy.However, the catalytic reduction of azo-dye Congo red dye was mesured by abdorbance value using spectro photo-meter, which is around 498 nm.Finally, reduction of Congo red dye was degraded colour less within 11 min, which is represented in (Fig. 7 A).Varadavenkatesan et al., (2016) reported the reduction of azo dye such as Methyl Orange [28].The catalytic activity of Copper Sulfide nanoparticles efficiece was tested for the reduction of Congo red to determined the following equation which is (%) of decolorization efficiency = (A0-At)×100/A0, Therefore, A0 is idicated to initial concentration of test pollutant dye medium (Congo red dye), At is denoted to time taken for the reduction of Congo red dye solution.Finally, concluded that Congo red dye was degraded colour less within 11 min up to 96.21% degradation which is represented in (Fig. 7 B).The redox potential difference between the electron accepting Congo red dye molecules and the electron donating molecules that is sodium borohydride ion is huge so that reason the electron transfer between the two species is more difficulty for the reduction of Congo red, Tartrazine dye molecules.Therefore, for the reduction of Congo red dye to particularly Copper sulphide nanoparticles was added the because of the nanoparticles mediated transfer of electrons from donor to accepter that is electron transfer from sodium borohydride to Congo red dye molecules.Therefore, here copper sulphide nanoparticles diminishing the activation energy barrier centres between sodium borohydride and dye molecules then leading to rapid advancement electron transfer to dye molecules then lead to reduction reaction rapidly occurs.represents the zone of inhibition of the bacteria against the synthesized Copper Sulfide nanoparticles were found to be zone of inhibition gram positive bacteria are 0 mm, 12 mm and 16 mm whereas for gram negative bacteria 18 mm, 24 mm and 30 mm respectivily.It was done against amoxicillin which was used as control for this antibacterial activity.The amoxicillin was taken in the concentration on the gram positive and gram negative bacteria as 20 µl, 40 µl and 60 µl.For the control used as a amoxicillin, the zone of inhibition for the control was found to be for gram positive bacteria are 16 mm, 20mm and 23mm whereas for gram negative bacteria 13 mm, 16 mm and 19 mm respectivily.

CuS NPs in S. aureus
CuS NPs in P. aeruginosa  weighed an dissolved in 10 mL of distilled water.Finally, 1 mL of DPPH solution was measured and added into the 10 test tubes.To 1 ml of DPPH varying concentration of ascorbic acid from 50 µl to 250 µl was added into 5 test tubes and Copper Sulfide nanoparticles concentration from 50 µl to 250 µl was added to other 5 test tubes and the ten test tubes were kept in dark for 30 mins and the absorbance was recorded at 517 nm using by UV-Visible spectroscopy.The % of inhibition was calculated by using the absorbance values and to calculate the % of inhibition by using following formula % of inhibition = (Cc -Ct / Ct) * 100 The % of inhibition increases as the concentration of the test sample was increases.The initially % of inhibition was found to be around 29.33% at concentration of 50 µl and its was increases with increase of the nanoparticles doses [30].Finally, at the 250 µl concentration the inhibition was found to be 88.50%.Fig. 10 represents the antioxidant activity of the Copper Sulfide nanoparticles.The graph shows that the synthesized CuS NPs has good oxidation property towards DPPH in reference to ascorbic acid.Fig. 10 shows the clearly DPPH in the initial purple colour and in the final stage tested with copper sulphide nanoparticles its is yellow colour so from that concluded radical reaction occurs in the presence of nanoparticles.

Conclusion
In this study, a simple, cost effective and convenient way developed Copper Sulfide nanoparticles through the green process.The synthesized nanomaterials were carried out various host of analytical technique such as the Copper Sulfide nanoparticles were confirmed through UV -Visible spectroscopy, the functional groups present in Boswellia Ovalifoliolata leaves extract, and Copper Sulfide nanoparticles were confirmed through FT-IR spectroscopy.The crystal structure and the average crystalline size of the synthesised nanoparticles were confirmed through XRD analysis and average crystalline size is 11 nm.The size of the synthesised Copper Sulfide nanoparticles was confirmed through SEM /doi.org/10.1051/e3sconf/20234300115050 430

Fig. 1
Fig. 1 UV -Visible spectroscopy for the formation of Copper Sulfide Nanoparticles

Fig. 3
Fig. 3 FT-IR analysis of the Boswellia Ovalifoliolata leaves extract

Fig. 4 FT
Fig. 4 FT -IR analysis of the Copper Sulfide Nanoparticles

Fig. 5
Fig. 5 SEM and EDAX results of Copper Sulfide Nanoparticles

Fig. 6
Fig. 6 Reduction of Tartrazine azo dye (A) by in the presence of Copper Sulfide nanoparticles and % of azo dye degradation removal with respect to time intervals (B) /doi.org/10.1051/e3sconf/20234300115050 430

Fig. 7 Fig. 8 5 . 8
Fig. 7 Reduction of Congo red azo dye (A) by in the presence of Copper Sulfide nanoparticles and % of azo dye degradation removal with respect to time intervals (B)

Fig. 9
Fig. 9 Images of antibacterial activity of gram positive and gram negative bacteria against Copper Sulfide Nanoparticles

Fig. 10
Fig. 10 Antioxidant activity of Copper Sulfide Nanoparticles /doi.org/10.1051/e3sconf/20234300115050 430 analysis that is average size is around 38.43 nm.The applications for synthesised Copper Sulfide nanoparticles were carried out such as catalytic activity and antibacterial, antioxidant activity.The antibacterial activity was done with gram positive and gram negative bacteria that are Staphylococcus aureus, Pseudomonas aeruginosa.The synthesised Copper Sulfide nanoparticle has effectivily working on the gram positive bacteria.The results indicated that the synthesized Copper Sulfide nanomaterial are shows the excelent antioxidant activity against the free radical DPPH molecules.The biomolecules mediated Copper Sulfide nanoparticles are remarkable catalytic efficiency towards the pollutants Congo red, Tartrazine dye.

Table . 1
Zone of inhibition of Copper Sulfide Nanoparticles

5.9 Antioxidant activity of Copper Sulfide nanoparticles
Antioxidant activity was carried out with DPPH with con. of 50 ppm which was dissolved in methanol.The DPPH was prepared by addition of 15 ml of methanol to 1.5 mL of DPPH to make a 50 ppm of DPPH.The synthesized Copper Sulfide nanoparticles of 10 mg was weighed and dissolved in 10 mL of methanol and similarway, the ascorbic acid 10 mg was