DESC:[0030] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure. Further, the phraseology and terminology employed in the description is for the purpose of description only and not for the purpose of limitation.
[0031] The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, apparatus, system, assembly, method that comprises a list of components or a series of steps that does not include only those components or steps but may include other components or steps not expressly listed or inherent to such apparatus, or assembly, or device. In other words, one or more elements or steps in a system or device or process proceeded by “comprises… a” or “comprising …. of” does not, without more constraints, preclude the existence of other elements or additional elements or additional steps in the system or device or process as the case may be.
[0032] The primary object of the present invention is to provide a novel nanocomposite composition containing cerium and graphene oxide synthesized using flower extracts or bacterial media. The invention discloses a nano composite containing cerium and graphene oxide using a green process with floral extract of Calotropis gigantea and its application for inhibiting/reducing the colony formation and antibacterial activity against Streptococcus mutans is provided. The present invention envisages that the nanocomposite is cost effective and eco-friendly and is scalable for the its antibacterial and antibiofilm activity.
[0033] Reference may be made to Figure 1 illustrating the Scanning Electron microscopy (SEM) image of the GO, CeO2 and GO/CeO2 composite, in accordance with an embodiment of the present invention. SEM image of the Graphene oxide(GO), Cerium oxide (CeO2) and GO-CeO2 nanocomposites was taken to study the relevant structure of the nanoparticles and the nanocomposite and the images revealed the crystalline structure and orientation of materials making up the sample.
[0034] Reference may be made to Figure 2 illustrating the biofilm analysis of the composite, in accordance with an embodiment of the present invention. For this, the antibiofilm property was checked by the analysis of crystal violet absorbance in treated bacterial strains. Absorbance of crystal violet was found to decrease with increased concentration of GO/CeO2 composite indicating the increasing antibiofilm efficacy of GO/CeO2 composite for the disruption of biofilm formed by the S.mutans.
[0035] Reference may be made to Figure 3 illustrating the Dead-live qualitative analysis of S.mutans treated with Go-CeO nanocomposite(flower extract). The bacterial culture was treated with different concentration of nanocomposite and stained with Syto 9/PI to estimate the dead-live bacterial strains, in accordance with an embodiment of the present invention. Green fluorescence was exhibited by the live bacteria, while the red fluorescence was exhibited by the dead bacteria. The yellow fluorescence inferred the bacterial strains with damaged membrane which are about to die. The red fluorescence was found to be increased with increase in treatment concentration of nanocomposite (GO-CeO2 nanocomposite comprising flower extract), in turn indicating the concentration-dependent antibacterial activity of the nanocomposite comprising of the Calotropis flower extract synthesized by the green process.
[0036] Reference may be made to Figure 4 illustrating the quantitative analysis of S.mutans treated with Go-CeO nanocomposite represented by the Bar graph presenting the comparative dead percentage of bacteria (data in log scale) treated with different concentrations of GO, CeO NP and Go/CeO Np composite (flower extract), in accordance with an embodiment of the present invention. The quantification of the fluorescence was performed through Image J analysis. The data presented higher efficacy of GO/CeO NP composite (comprising flower extract) compared to GO nanoparticle and CeO2 nanoparticle alone.
[0037] Reference may be made to Figure 5 illustrating the Dead-live qualitative analysis of S.mutans treated with Go-CeO nanocomposite (bacterial media). The bacterial culture was treated with different concentration of nanocomposite and stained with Syto 9/PI to estimate the dead-live bacterial strains, in accordance with an embodiment of the present invention. Green fluorescence was exhibited by the live bacteria, while the red fluorescence was exhibited by the dead bacteria. The yellow fluorescence inferred the bacterial strains with damaged membrane which are about to die. The red fluorescence was found to be increased with increase in treatment concentration of nanocomposite (GO-CeO2 nanocomposite comprising bacterial), in turn indicating the concentration-dependent antibacterial activity of the nanocomposite comprising of the bacterial media synthesized by the green process.
[0038] Reference may be made to Figure 6 illustrating the quantitative analysis of S.mutans treated with Go-CeO nanocomposite represented by the Bar graph presenting the comparative dead percentage of bacteria (data in log scale) treated with different concentrations of GO, CeO NP and Go/CeO Np composite (bacterial media), in accordance with an embodiment of the present invention. The quantification of the fluorescence was performed through Image J analysis. The data presented higher efficacy of GO/CeO NP composite (comprising bacterial media) compared to GO nanoparticle and CeO2 nanoparticle alone.
[0039] Reference may be made to Figure 7 illustrating the Bar Graph presenting the percentage of dead cells (data in log scale) of S.mutans in the presence of different concentration of Go/CeO2 composite (with flower extract) analyzed through Flow cytometry, in accordance with an embodiment of the present invention. The dead percentage was found to be increased with increase in concentration of the composite. The cells were stained with Syto 9 for live cell analysis and Propidium iodide for dead cells analysis. The analysis was performed in ATTUNE focusing cytometer (Thermo Fisher scientific) and the data inferred the concentration dependent antibacterial activity of GO/CeO2 composite (with flower extract).
[0040] Reference may be made to Figure 8 illustrating the Histogram presentation of the mean fluorescence intensity (MFI) of DCFDA fluorescence presenting the induced Reactive oxygen species(ROS) in S.mutans treated with different concentration of (A) GO (B) CeO NP (C) Go/CeO2 composite (Flower extract) analyzed by Flow cytometry, in accordance with an embodiment of the present invention. 2',7'–dichlorofluorescin diacetate (DCFDA) assay was done for the real time monitoring and quantification of reactive oxygen species in S.mutans treated with different concentration of (A) GO (B) CeO NP (C) Go/CeO2 composite (Flower extract). . From the data it was inferred that there was comparative higher induction of ROS by Go/CeO2 nanocomposite comprising of Flower extract as compared to the GO and CeO alone indicating higher antibacterial activity
[0041] Nanocomposites are widely applied to human contact areas and there is a growing need to develop processes for synthesis that do not use harsh toxic chemicals. Therefore, a green/biological process for synthesis of nanoparticles is a possible alternative to chemical and physical methods. The particles produced by green synthesis differ from those using physico–chemical approaches. Green synthesis, a bottom-up approach, is similar to chemical reduction where an expensive chemical reducing agent is replaced by extract of a natural product such as leaves of trees/crops or fruits for the synthesis of metal or metal oxide nanoparticles. Use of environmentally friendly solvents and conditions of the green synthesis process results in reduced energy consumption and waste generation. Further, unique properties are influenced by the biomolecules or bio entities involved in the green process which is devoid of any hazardous materials, whereas chemical process tends to generate more chemical waste, utilize higher energy consumption, in turn leading to a higher environmental impact. Biological production of nanoparticles allows recycle of expensive metal salts like gold and silver contained in waste streams.
[0042] The thermal and mechanical properties of graphene help in strengthening and increasing the interfacial bonds between the layers of graphene and the host matrix upon distribution, which in turn dictates the cumulative properties of graphene in reinforced nanocomposites. The nanocomposite synthesized by the green process has remarkable effects against S. mutans in the biofilm formation along with antibacterial activity. Biosynthesis of nanocomposite using plant extracts is one of the very effective, rapid, clean, non-toxic and eco-friendly methods.
[0043] In an embodiment of the present invention, the invention discloses an antimicrobial nanocomposite composition synthesized through a green process comprising of at least a first suspension comprising of nanoparticles of Cerium and Graphene in a ratio of 1:99 V/V; at least a second suspension comprising one of a bacterial media, plant extracts, bio-inspired materials as reducing agents, precursors. In an embodiment, the ratio of the first suspension comprising nanoparticles with the second suspension is 1:3 V/V and is synthesized by the green process.
[0044] In another embodiment of the present invention, the nanoparticles of Cerium in the first suspension comprises Cerium oxide.
[0045] In yet another embodiment of the present invention, the nanoparticles of Graphene in the first suspension comprises Graphene oxide and modifications of graphene oxide.
[0046] In an embodiment of the present invention, the bacterial extract in the second suspension comprises at least one selected from gram-negative bacteria.
[0047] In an embodiment of the present invention, the plant extract in the second suspension comprises at least one selected from aqueous floral extract of Calotropis gigentea.
[0048] In an embodiment of the present invention, the bio-inspired materials is at least one selected from reducing agents and precursors.
[0049] In a preferred embodiment of the present invention, Cerium Oxide (CeO2) and Graphene Oxide (GO) nanocomposite is made by mixing GO and CeO2 nanoparticles (NP) at a ratio of 1:100 (V/V). For the green synthesis of the nanocomposite, GO and CeO NP is used as a precursor and aqueous floral extract of Calotropis gigentea is used as a reducing and stabilizing agent. The invention discloses a green process for synthesis of antimicrobial nanocomposite composition, comprising the steps: a) preparing a first suspension byi) taking graphene oxide nanoparticles. Graphene oxide is dispersed in distilled water and sonicated at 70Amp for 10 min. Followed by sonication, Calotropis gigentea floral extract is mixed in a ratio of 1:1(V/V) and stirred for 30 min with an adjustment of pH to 4.0 using NaOH(1mM). This modified Graphene oxide nanoparticles is washed twice and re- dispersed in distilled water to get the desired sized Graphene oxide nanoparticle to be used in the green synthesis; (ii) taking cerium oxide nanoparticles in size <5.0nm ; (iii) mixing the nanoparticles from steps (i) and (ii) in a ratio of 1:99 (V/V) using a green reducing agent or bio-inspired method to form a nanoparticle composite; b) preparing a second suspension comprising at least aqueous floral extract of Calotropis gigantea wherein, aqueous floral extract of Calotropis gigentea is prepared by boiling 5 g chopped floral part comprising at least one selected from Petals, sepals, and inner part, in distilled water for 15 minutes, followed by filtering with the help of muslin cloth and cooling to obtain a supernatant to be used as the second suspension in the synthesis reaction; c) setting up a synthesis reaction by incubating the second suspension from step (b) with the first suspension in a ratio of 1:3 V/V. For setting up the synthesis reaction, floral extract is incubated with 1mM GO and CeO2 NP solution in a ratio of 1:3 V/V. The synthesis reaction is then exposed to UV-light for 3 hours in stirring condition. The synthesized CeO2 and GO nanocomposite (CeO2/GO NC) is then centrifuged, lyophilized and suspended in distilled water. This is the final Graphene and Cerium Oxide Nanocomposite synthesized by the green process of the present invention. The presence of graphene oxide improves the stability and dispersibility of CeO2 nanoparticles in various matrices or environments, preventing agglomeration and enhancing their overall performance and longevity.
[0050] In an embodiment of the present invention, the green reducing agent and stabilizing agent comprises a plant extract, vitamin C, or a combination thereof.
[0051] In a preferred embodiment of the present invention, the invention discloses a green process for synthesis of antimicrobial nanocomposite composition, comprising the steps: a) preparing a first suspension by mixing Graphene oxide nanoparticles and Cerium oxide nanoparticles by: i) taking graphene oxide nanoparticles wherein the graphene oxide nanoparticle is synthesized by dispersing the Graphene oxide in distilled water and sonicating them at 70Amp for 10 min, followed by sonication. The Calotropis gigentea floral extract is mixed in a ratio of 1:1(V/V), followed by stirring for 30 min with an adjustment of pH to 4.0 using NaOH(1mM); wherein the modified Graphene oxide nanoparticles is washed twice and re- dispersed in distilled water to be used as Graphene Oxide nanoparticle with the desired particle size (ii) taking cerium oxide nanoparticles in size <5.0nm (iii) mixing the nanoparticles from steps (i) and (ii) in a ratio of 1:99 (V/V) using a green reducing agent or bio-inspired method to form a nanoparticle composite and this is the nanoparticle suspension; b) preparing a second suspension comprising at least bacterial media wherein, the bacterial media for use as the second suspension is prepared by centrifuging the Luria-Bertani (LB) media used for the growth of S. mutans bacterial strain followed by filtering to obtain a supernatant for use as the second suspension; c) setting up a synthesis reaction by incubating the second suspension from step (b) with the first suspension in a ratio of 1:3 V/V. Synthesis reaction was set up by incubating the bacterial extract with 1mM GO and CeO2 NP solution in a ratio of 1:3 V/V and this was then exposed to UV-light for 3 hours in stirring condition. This synthesized Ce and GO nanocomposite (CeO/GO NC) was then centrifuged, lyophilized and suspended in distilled water. This was the final Graphene and Cerium Oxide Nanocomposite synthesized by the green process. In this embodiment of the present invention, GO and CeO2 NP was used as a precursor and bacterial media extract was used for the green process in place of the aqueous flower extract as a reducing and stabilizing agent.
[0052] For the preparation of the bacterial media extract, S. mutans bacterial strain was grown in the “Luria-Bertani" medium and after centrifuging the supernatant bacteria media obtained as a bacterial extract, was used as a second suspension for the green process. The extract was then cooled and this aqueous extract was further used for the nanocomposite synthesis reaction setup.
[0053] In an embodiment of the present invention, the green reducing agent and stabilizing agent comprises a plant extract, vitamin C, or a combination thereof.
[0054] In an embodiment of the present invention, the nanoparticles have an average particle size in the range of 1-100 nanometers.
Example:
[0055] In the method of the present invention, the aqueous flower extract of Calotropis gigantea was used as a reducing and stabilizing agent and the nanocomposite was synthesized which was further characterized. The synthesized cerium oxide graphene oxide nanoparticle composite were characterized using spectroscopic and microscopic techniques, including SEM, TEM, XRD, FTIR, and Raman spectroscopy.
[0056] Scanning Electron Microscopy (SEM analysis): Scanning Electron Microscopy analysis, SEM image of the Graphene oxide(GO), Cerium oxide (CeO2) and GO-CeO2 nanocomposites (GO/CeO2 NC ) was taken to study the relevant structure of the nanoparticles and the nanocomposite (FIGURE 1). The two different nanocomposites were synthesized using green methodology in the presence of Bacterial extract and floral extract (C. gigentea) as reducing and stabilizing agent and the images revealed the crystalline structure and orientation of materials making up the sample.
[0057] Dynamic Light Scattering for Zeta potential and Hydrodynamic size determination: The optical scattering properties of a solution containing the particles are used to determine the size and stability of the particle through dynamic light scattering method. Zeta potential analysis in biological samples provides an insight into the cellular uptake of particles and the presence of biomarkers. Zeta potential was checked to study the stability of particles in solution and the potential of aggregation of particles. For this, the size and stability of GO NP, CeO2 NP and GO/CeO2 NC in aqueous medium was assessed by determination of hydrodynamic diameter and zeta potential by Zetasizer (Malvern, UK).
[0058] The size of the synthesized nanomaterials was determined through dynamic light scattering in the aqueous medium. Graphene oxide nanosheets was found to have a hydrodynamic diameter of 1068 nm, which represents that there was Graphene sheet formation. However, a small peak was also observed at 317.3nm which represented the dislocation of some of the nanosheets from its original position during the process of formation. In case of CeO2 NP there was very high non uniformity with three different types of particle sizes in the solution. The sizes were 3.641, 49.50 and 1.559 nm in descending order of their percentage intensity. While after the formation of Graphene oxide- cerium oxide Nanocomposites, it was clearly seen that that there was a uniform structure of 288.9 nm, confirming the solution containing the NC with a uniform size. However, there was presence of a very low intensity of other particles at 5411nm which were negligible.
[0059] Further, in order to find out the stability of nanomaterials, their zeta potential was measured using the Zetasizer. As shown in Table 1, the Zeta potential of GO NP was found to be -55.5 mV depicting that it was a stable particle. In case of CeO NP it was -16.7 mV indicating that, both of them are stable in the solution for a long time. The zeta potential of GO/CeO NC was recorded as -50.2 mV and -64.1 mV presenting the excellent stable behavior of the synthesized nanocomposites. Thus, the analysis confirmed the stability of the GO, CeO2 and synthesized GO/CeO2 nanocomposites in aqueous medium (Table 1).
[0060] Table 1: Zeta potential of GO, CeO2 and GO/CeO2 nanocomposites
S.N Material Zeta Potential
1. GO -55.5 ± 7.1 mV
2. CeO -16.7 ± 6.2 mV
3. GO/CeO NC (Bacterial extract) -50.2 ± 6.8 mV
4. GO/CeO NC (Flower extract) -64.1 ± 11.3 mV

[0061] Antibiofilm property of GO/CeO2 nanocomposite: The cerium oxide-graphene oxide nanoparticle composite synthesized by the green process exhibiting enhanced biocompatibility, reduced toxicity, and improved catalytic properties was compared to conventionally synthesized counterparts. For this, the antibiofilm property was checked by the analysis of crystal violet absorbance in treated bacterial strains. The 72h cultured bacterial strains were treated by the Nanocomposites and stained with crystal violet for 15 min. Absorbance of crystal violet was found to decrease with increased concentration of GO/CeO2 composite indicating the increasing antibiofilm efficacy of GO/CeO2 composite for the disruption of biofilm formed by the S.mutans. The results in turn confirmed that the cerium oxide-graphene oxide nanoparticle composite synthesized by the green process had remarkable effects against S. mutans in the biofilm formation along with antibacterial activity (FIGURE 2).
[0062] SYTO 9/Propidium Iodide (PI) staining: To study the the concentration-dependent antibacterial activity of the nanoconjugate, dead-live qualitative analysis of S.mutans treated with Go-CeO2 nanocomposite was done. For this, the bacterial culture was treated with different concentration of nanocomposite and stained with Syto 9/PI to estimate the dead-live bacterial strains. Green fluorescence was exhibited by the live bacteria, while the red fluorescence was exhibited by the dead bacteria. The yellow fluorescence inferred the bacterial strains with damaged membrane which are about to die.
[0063] (i) For GO-CeO2 nanocomposite comprising flower extract: The red fluorescence was found to be increased with increase in treatment concentration of nanocomposite (GO-CeO2 nanocomposite comprising flower extract). The results in turn indicated the concentration-dependent antibacterial activity of the nanocomposite comprising of the Calotropis flower extract synthesized by the green process (FIGURE 3).
For Quantitative studies: The analysis was done with counting the treated bacterial strains stained with Syto9/PI. The quantification of the fluorescence was performed through Image J analysis. Bar graph presenting the comparative dead percentage of bacteria (data in log scale) treated with different concentrations of GO, CeO NP and GO/CeO NP composite (comprising flower extract) were shown in FIGURE 4. The data presented higher efficacy of GO/CeO NP composite (comprising flower extract) compared to GO nanoparticle and CeO2 nanoparticle alone.
[0064] (ii) For GO-CeO2 nanocomposite comprising bacterial media: Similar studies for studying the efficacy of the GO-CeO2 nanocomposite comprising bacterial media, by dead-live qualitative analysis of S.mutans treated with different nanoparticles. In this the bacterial culture was treated with different concentration of nanocomposite (Go-CeO2 nanocomposite comprising bacterial media) and stained with Syto 9/PI to estimate the dead-live bacterial strains. Green fluorescence was exhibited by the live bacteria, while the red fluorescence was exhibited by the dead ones. The yellow fluorescence inferred the bacterial strains with damaged membrane which were about to die in due course of time. The red fluorescence was found to be increased with increase in treatment concentration of nanocomposite. The data indicated the concentration-dependent antibacterial activity of the nanocomposite comprising of the bacterial media synthesized by the green process (FIGURE 5).
For Quantitative studies: The analysis was done with counting the treated bacterial strains stained with Syto9/PI. The quantification of the fluorescence was performed through Image J analysis. Bar graph presenting the comparative dead percentage of bacteria (data in log scale) treated with different concentrations of GO, CeO NP and Go/CeO Np composite (bacterial media) were shown in FIGURE 6. The data presented higher efficacy of GO/CeO NP composite (comprising bacterial media) compared to GO nanoparticle and CeO2 nanoparticle alone.
[0065] Flow cytometry Analysis: Bar Graph presenting the percentage of dead cells (data in log scale) of S.mutans in the presence of different concentration of Go/CeO2 composite was analyzed through Flow cytometry. The dead percentage was found to be increased with increase in concentration of the composite. The cells were stained with Syto 9 for live cell analysis and Propidium iodide for dead cells analysis. The analysis was performed in ATTUNE focusing cytometer (Thermo Fisher scientific). The data inferred the concentration dependent antibacterial activity of GO/CeO2 composite (FIGURE 7).
[0066] DCFDA experiment to study the Reactive Oxygen Species: 2',7'–dichlorofluorescin diacetate (DCFDA) assay was done for the real time monitoring and quantification of reactive oxygen species in S.mutans treated with different concentration of (A) GO (B) CeO NP (C) Go/CeO2 composite (Flower extract). The Histogram presentation of the mean fluorescence intensity (MFI) of DCFDA fluorescence presented the induced Reactive oxygen species (ROS) in S.mutans treated with different concentration of (A) GO (B) CeO NP (C) Go/CeO2 composite (Flower extract) which was analyzed by Flow cytometry. The DCFDA fluorescence was found to be increased with an increase in concentration of the composite indicating the higher induction of ROS with increasing concentration. The analysis was performed in ATTUNE focusing cytometer (Thermo Fisher scientific). (D) bar graph represented a comparative assessment of the MFI. From the data it is inferred that there is comparative higher induction of ROS by Go/CeO2 nanocomposite comprising of Flower extract as compared to the GO and CeO alone indicating higher antibacterial activity (FIGURE 8).
[0067] ADVANTAGES OF THE INVENTION
[0068] Graphene based nanocomposites when combined with cerium and other materials make those materials one of the most exciting platforms in many areas of materials for healthcare. Proteins and peptide sequences used in graphene composites improve the attachment of cells to the surface of tissue scaffold in regenerative medicine applications. Further advantage of graphene materials, unlike some other biomaterials such as metals, is the ability of cells to adhere directly to a variety of graphene surfaces and to spread and proliferate on these surfaces without apparent adverse effects. Further it is a green process to develop better and advanced formulations to combat specific dental pathogens and maintain healthy oral environment.
• A green synthesis method for the synthesis of Nanocomposite of cerium and grapheme oxide using leaf extract is eco-friendly and cost-effective.
• The activity of this Nanocomposite is better than the materials (Nanoparticles) when used individually.
• an antimicrobial nanocomposite composition may be used for medical devices and others.
• as compared with the existing nanocomposites the present invention discloses an eco-friendly and cost-effective green process for the synthesis of cerium and grapheme oxide nanocomposites by using Calotropis leaf extract.
[0069] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0070] Although embodiments for the present invention have been described in language specific to structural features, it is to be understood that the present invention is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present invention. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present invention.
,CLAIMS:WE CLAIM:
1. An antimicrobial nanocomposite composition synthesized through a green process comprising:
a) At least a first suspension comprising of nanoparticles of Cerium and Graphene in a ratio of 1:99 V/V;
b) at least a second suspension comprising one of a bacterial media, plant extracts, bio-inspired materials as reducing agents, precursors;
wherein the ratio of the first suspension comprising nanoparticles with the second suspension is 1:3 V/V and is synthesized by the green process.
2. The nanocomposite as claimed in claim 1 wherein, the nanoparticles of Cerium in the first suspension comprises Cerium oxide.
3. The nanocomposite as claimed in claim 1 wherein, the nanoparticles of Graphene in the first suspension comprises Graphene oxide.
4. The nanocomposite as claimed in claim 1 wherein, the bacterial extract in the second suspension comprises at least one selected from gram-negative bacteria.
5. The nanocomposite as claimed in claim 1 wherein, the plant extract in the second suspension comprises at least one selected from aqueous floral extract of Calotropis gigantea.
6. The nanocomposite as claimed in claim 1 wherein, the bio-inspired materials is at least one selected from reducing agents, precursors.
7. A green process for synthesis of antimicrobial nanocomposite composition, comprising the steps:
a) preparing a first suspension by mixing Graphene oxide nanoparticles and Cerium oxide nanoparticles by: i) taking graphene oxide nanoparticles, wherein the graphene oxide nanoparticle is synthesized by treating Graphene oxide with Calotropis gigentea floral extract in a ratio of 1:1(V/V) to form their structure as nanoparticles (ii) taking cerium oxide nanoparticles in size <5.0nm (iii) mixing the nanoparticles from steps (i) and (ii) in a ratio of 1:99 (V/V) to form GO-CeO2 nanoparticle suspension;
b) preparing a second suspension comprising at least aqueous floral extract of Calotropis gigantea wherein, aqueous floral extract of Calotropis gigentea is prepared by boiling 5 g chopped floral part comprising at least one selected from Petals, sepals, and inner part, in distilled water for 15 minutes, followed by filtering and cooling to obtain a supernatant to be used as the second suspension;
c) setting up a synthesis reaction by incubating the second suspension from step (b) with the first suspension in a ratio of 1:3 V/V; and
d) exposing the composition from step (c) to UV-light for 3 h in stirring condition, followed by centrifuging, lyophilizing and suspending in distilled water to prepare the nanocomposite.
8. A green process for synthesis of antimicrobial nanocomposite composition, comprising the steps:
a) preparing a first suspension by mixing Graphene oxide nanoparticles and Cerium oxide nanoparticles by: i) taking graphene oxide nanoparticles, wherein the graphene oxide nanoparticle is synthesized by treating Graphene oxide with Calotropis gigentea floral extract in a ratio of 1:1(V/V) to form their structure as nanoparticles (ii) taking cerium oxide nanoparticles in size <5.0nm (iii) mixing the nanoparticles from steps (i) and (ii) in a ratio of 1:99 (V/V) to form a GO-CeO2 nanoparticle suspension;
b) preparing a second suspension comprising at least bacterial media wherein, the bacterial media for use as the second suspension is prepared by centrifuging the LB media used for the growth of S. mutans bacterial strain followed by filtering to obtain a supernatant for use as the second suspension;
c) setting up a synthesis reaction by incubating the second suspension from step (b) with the first suspension in a ratio of 1:3 V/V; and
d) exposing the composition from step (c) to UV-light for 3 h in stirring condition, followed by centrifuging, lyophilizing and suspending in distilled water to prepare the nanocomposite.
9. The method as claimed in claim 7 or claim 8, wherein the graphene oxide nanoparticle is synthesized by (i) dispersing the Graphene oxide in distilled water and sonicating them at 70Amp for 10 min; (ii) followed by sonication, Calotropis gigentea floral extract is mixed in a ratio of 1:1(V/V), followed by stirring for 30 min with an adjustment of pH to 4.0 using NaOH(1mM); wherein the modified Graphene oxide nanoparticles is washed twice and re- dispersed in distilled water to be used as Graphene Oxide nanoparticle with the particle size of .
10. The antimicrobial nanocomposite composition of the claimed invention, wherein the nanoparticles have an average particle size in the range of 1-100 nanometers.
Dated 25th day of December 2022