NOVEL GREEN SYNTHESIZED FLUORESCENT CARBON DOTS FOR HEAVY METAL ION SENSING APPLICATIONS

Abstract

ABSTRACT “NOVEL GREEN SYNTHESIZED FLUORESCENT CARBON DOTS FOR HEAVY METAL ION SENSING APPLICATIONS” The present invention relates to green-synthesized fluorescent carbon dots (CDs) for detecting heavy metal ions, specifically arsenic (III). The CDs are synthesized using Tabernaemontana divaricata leaf extract as a novel carbon precursor, with cysteine incorporated to enhance fluorescence. The resulting sulfur- and nitrogen-doped carbon dots exhibit excellent water solubility, high fluorescence quantum yield, and significant photoluminescence quenching when exposed to arsenic (III) ions. This quenching occurs via energy transfer due to selective interactions between the CDs' surface functional groups (oxygen, nitrogen, sulfur) and metal ions. The CDs demonstrate selective and sensitive detection of arsenic (III) with greater efficiency compared to other heavy metals. These carbon dots are low in toxicity, environmentally friendly, and stable in aqueous environments, making them suitable for environmental monitoring applications to detect heavy metal contaminants, particularly arsenic (III). Figure 1

Specification

Description:TECHNICAL FIELD
[0001] The present invention relates to the field of artificial intelligence and automated systems, and more particularly, the present invention relates to the novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications.
BACKGROUND ART
[0002] The following discussion of the background of the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was published, known, or part of the common general knowledge in any jurisdiction as of the application's priority date. The details provided herein the background if belongs to any publication is taken only as a reference for describing the problems, in general terminologies or principles or both of science and technology in the associated prior art.
[0003] This patent application presents a novel green synthesized sulfur and nitrogen doped fluorescent carbon dots (CDs) designed for heavy metal ion sensing applications.
[0004] Traditional methods for synthesizing CDs often involve toxic substances and harsh conditions. In contrast, the disclosed method utilizes green chemistry principles, employing renewable plant-derived precursors to produce CDs with exceptional fluorescence properties. These green-synthesized CDs exhibit high sensitivity and selectivity for detecting heavy metal ions, offering a sustainable and effective solution for environmental monitoring.
[0005] Environmental pollutants such as heavy metals are well known for their toxicity, longevity in the atmosphere, and ability to accumulate in the human body. The human body is frequently exposed to toxic contaminants and pollutants, either directly through drinking water or food or through skin absorption. Heavy metal ions (e.g. As3+, Pb2+, Hg2+, Cu2+, Cd2+, Ag+, etc.) are non-biodegradable, so the accumulation of these ions in human tissues through the food chain leads to serious health problems, including allergies, kidney failure, neurotoxicity, oxidative toxicity, and apoptosis. By displacing original metals from their natural binding sites, these heavy metals bind with protein sites, causing malfunctioning of cells and ultimately toxicity.
[0006] Nanomaterials such as carbon dots (CDs), carbon quantum dots, metal nanoparticles, graphene, fullerene, and others are used to detect toxic heavy metal ions. Among all sensors, CDs are highly fluorescent material which is the most effective and efficient for the selective detection of heavy metals. Traditionally, the synthesis of Carbon Dots (CDs) is carried out by using conventional chemical methods, however, these methods often involve toxic chemicals and energy-intensive processes, leading to environmental concerns and safety hazards. Thus, it is crucial to investigate green synthesis methods for producing CDs, as opposed to traditional approaches.
[0007] The disclosed method addresses these issues by employing green chemistry principles, utilizing renewable plant-derived precursors as starting materials. Green synthesis methods provide several advantages, such as reduced production of toxic byproducts, lower energy consumption, eco-friendly, cost-effective, and scalability for large-scale production. Additionally, nanoparticles produced using plant extracts have shown effective binding affinity for heavy metal ions, making them ideal for use in sensing applications. Therefore, we have developed novel sulfur and nitrogen-doped carbon dot nanoparticles with a great photoluminescence property for sensing of heavy metal ions.
[0008] Traditionally, numerous techniques such as ion-selective electrodes, atomic absorption spectroscopy, chelation and precipitation, and colorimetric methods have been utilized for detecting and degrading metal ions.
[0009] Traditionally synthesized Carbon dots (CDs) through methods such as arc discharge, laser ablation, and chemical oxidation, which often involve toxic substances, high temperatures, and energy-intensive conditions. These conventional processes can generate hazardous byproducts and offer restricted control over the size, shape, and surface properties.
[0010] Green synthesis techniques present eco-friendly alternatives by employing renewable resources, non-toxic solvents, and gentle reaction conditions, thus providing a more sustainable approach to CD production. Several methods for green synthesis including carbonization derived from biomass, synthesis assisted by microwave, and the hydrothermal technique, have been used by using different plant, fruit, and flower extracts as precursors.
[0011] The utilization of Tabernaemontana divaricata leaf extract for the synthesis of carbon dots has not been previously reported.
[0012] In light of the foregoing, there is a need for Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications that overcomes problems prevalent in the prior art associated with the traditionally available method or system, of the above-mentioned inventions that can be used with the presented disclosed technique with or without modification.
[0013] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies, and the definition of that term in the reference does not apply.
OBJECTS OF THE INVENTION
[0014] The principal object of the present invention is to overcome the disadvantages of the prior art by providing Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications.
[0015] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications wherein the formulation is innovative, involving the synthesis of sulfur and nitrogen-doped carbon dots using Tabernaemontana divaricata leaf extract as a precursor.
[0016] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications wherein the sulfur and nitrogen-doped carbon dots have never been synthesized using Tabernaemontana divaricata leaf extract.
[0017] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications wherein the Tabernaemontana divaricata leaf extract-derived carbon dots have not previously been utilized in heavy metal sensing applications, highlighting the uniqueness of this approach.
[0018] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications wherein the green-synthesized carbon dots have garnered interest due to their sustainable nature, affordability, biocompatibility, and user-friendly characteristics.
[0019] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications that wherein our formulation i.e. sulfur and nitrogen-doped carbon dots utilized in fluorescent sensing offer numerous benefits, such as rapid detection, good metal ion sensitivity, and excellent selectivity in detecting arsenic (III).
[0020] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications that holds tremendous potential to be used in sensing applications for heavy toxic metal ions.
[0021] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications wherein the synthesis of CDs is optimized for rapid and reliable detection of heavy metal ions with high accuracy.
[0022] Another object of the present invention is to provide Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications wherein the synthesized nanoparticles possess surface thiol groups, which augment their ability to bind efficiently with heavy metals like arsenic (As3+).
[0023] The foregoing and other objects of the present invention will become readily apparent upon further review of the following detailed description of the embodiments as illustrated in the accompanying drawings.
SUMMARY OF THE INVENTION
[0024] The present invention relates to Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications. This method describes green synthesis of novel sulfur and nitrogen-doped fluorescent carbon dots from an unreported Tabernaemontana divaricata leaf extract as a green precursor for the detection of As3+ ions. The synthesized carbon dots are water-soluble and have low toxicity and great photoluminescence properties. This formulation shows significant photoluminescence quenching for heavy metal ions i.e. As3+. The synthesized carbon dots exhibit quenching for other heavy metal ions also, but arsenic (III) quenching is more than other heavy metal ions.
[0025] We have developed novel green synthesized sulfur and nitrogen-doped fluorescent carbon dots using Tabernaemontana divaricata leaf extract as a carbon source. Tabernaemontana divaricate leaf extract has never been used for the synthesis of carbon dots. Carbon dots derived from Tabernaemontana divaricata leaf extract have not been previously employed for heavy metal ion sensing applications, specifically for arsenic (III) detection. Synthesized carbon dots exhibit good photoluminescence and metal quenching properties. Carbon dots have been employed for sensitive and selective colorimetric and fluorometric sensing of metal ions due to the presence of surface groups. These groups coordinate with metal ions, leading to photoluminescence (PL) quenching. The selective interactions between the functional groups and surface traps on the nanocarbon and the metal ions facilitate energy transfer, which is primarily responsible for photoluminescence quenching. The synthesized nanoparticles feature surface thiol groups, enhancing their affinity to bind more effectively with heavy metals such as arsenic (As3+). The green-synthesized CDs exhibit low toxicity and excellent stability in aqueous environments, making them suitable for environmental sensing applications.
[0026] While the invention has been described and shown with reference to the preferred embodiment, it will be apparent that variations might be possible that would fall within the scope of the present invention.
BRIEF DESCRIPTION OF DRAWINGS
[0027] So that the manner in which the above-recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may have been referred by embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
[0028] These and other features, benefits, and advantages of the present invention will become apparent by reference to the following text figure, with like reference numbers referring to like structures across the views, wherein:
[0029] Fig. 1 Schematics of synthesis and application of novel fluorescent carbon dots.
DETAILED DESCRIPTION OF THE INVENTION
[0030] While the present invention is described herein by way of example using embodiments and illustrative drawings, those skilled in the art will recognize that the invention is not limited to the embodiments of drawing or drawings described and are not intended to represent the scale of the various components. Further, some components that may form a part of the invention may not be illustrated in certain figures, for ease of illustration, and such omissions do not limit the embodiments outlined in any way. It should be understood that the drawings and the detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claim.
[0031] As used throughout this description, the word "may" is used in a permissive sense (i.e. meaning having the potential to), rather than the mandatory sense, (i.e. meaning must). Further, the words "a" or "an" mean "at least one" and the word "plurality" means "one or more" unless otherwise mentioned. Furthermore, the terminology and phraseology used herein are solely used for descriptive purposes and should not be construed as limiting in scope. Language such as "including," "comprising," "having," "containing," or "involving," and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents, and additional subject matter not recited, and is not intended to exclude other additives, components, integers, or steps. Likewise, the term "comprising" is considered synonymous with the terms "including" or "containing" for applicable legal purposes. Any discussion of documents, acts, materials, devices, articles, and the like are included in the specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention.
[0032] In this disclosure, whenever a composition or an element or a group of elements is preceded with the transitional phrase "comprising", it is understood that we also contemplate the same composition, element, or group of elements with transitional phrases "consisting of", "consisting", "selected from the group of consisting of, "including", or "is" preceding the recitation of the composition, element or group of elements and vice versa.
[0033] The present invention is described hereinafter by various embodiments with reference to the accompanying drawing, wherein reference numerals used in the accompanying drawing correspond to the like elements throughout the description. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. In the following detailed description, numeric values and ranges are provided for various aspects of the implementations described. These values and ranges are to be treated as examples only and are not intended to limit the scope of the claims. In addition, several materials are identified as suitable for various facets of the implementations. These materials are to be treated as exemplary and are not intended to limit the scope of the invention.
[0034] The present invention relates to Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications.
[0035] The water-soluble novel fluorescent carbon dots were synthesized from Tabernaemontana divaricata leaf extract precursor.
[0036] Cysteine was used in the synthesis of carbon dots to enhance the fluorescent properties of the nanoparticles.
[0037] The green synthesized carbon dots exhibit strong brightness characterized by a significant molar absorption coefficient and a high fluorescence quantum yield when excited at the ideal wavelength. Additionally, it has oxygen, nitrogen, and sulfur-containing groups on its surface which effectively bind with the target heavy metals i.e. arsenic (III) resulting in fluorescence quenching.
[0038] The photoluminescence quenching occurs due to energy transfer between nanocarbons and metal ions via selective interactions facilitated by functional groups and surface traps.
[0039] The present invention relates to Novel green synthesized fluorescent carbon dots for heavy metal ion sensing applications. This method describes green synthesis of novel sulfur and nitrogen-doped fluorescent carbon dots from an unreported Tabernaemontana divaricata leaf extract as a green precursor for the detection of As3+ ions. The synthesized carbon dots are water-soluble and have low toxicity and great photoluminescence properties. This formulation shows significant photoluminescence quenching for heavy metal ions i.e. As3+. The synthesized carbon dots exhibit quenching for other heavy metal ions also, but arsenic (III) quenching is more than other heavy metal ions.
[0040] We have developed novel green synthesized sulfur and nitrogen-doped fluorescent carbon dots using Tabernaemontana divaricata leaf extract as a carbon source. Tabernaemontana divaricate leaf extract has never been used for the synthesis of carbon dots. Carbon dots derived from Tabernaemontana divaricata leaf extract have not been previously employed for heavy metal ion sensing applications, specifically for arsenic (III) detection. Synthesized carbon dots exhibit good photoluminescence and metal quenching properties. Carbon dots have been employed for sensitive and selective colorimetric and fluorometric sensing of metal ions due to the presence of surface groups. These groups coordinate with metal ions, leading to photoluminescence (PL) quenching. The selective interactions between the functional groups and surface traps on the nanocarbon and the metal ions facilitate energy transfer, which is primarily responsible for photoluminescence quenching. The synthesized nanoparticles feature surface thiol groups, enhancing their affinity to bind more effectively with heavy metals such as arsenic (As3+). The green-synthesized CDs exhibit low toxicity and excellent stability in aqueous environments, making them suitable for environmental sensing applications.
[0041] Various modifications to these embodiments are apparent to those skilled in the art from the description and the accompanying drawings. The principles associated with the various embodiments described herein may be applied to other embodiments. Therefore, the description is not intended to be limited to the 5 embodiments shown along with the accompanying drawings but is to be providing the broadest scope consistent with the principles and the novel and inventive features disclosed or suggested herein. Accordingly, the invention is anticipated to hold on to all other such alternatives, modifications, and variations that fall within the scope of the present invention and appended claims.
, Claims:CLAIMS
We Claim:
1) A method for synthesizing fluorescent carbon dots for heavy metal ion sensing, the method comprising:
- utilizing Tabernaemontana divaricata leaf extract as a green precursor to produce carbon dots;
- incorporating cysteine to enhance fluorescent properties; and
- generating carbon dots characterized by water solubility, sulfur and nitrogen doping, and the presence of surface groups containing oxygen, nitrogen, and sulfur.
2) The method as claimed in Claim 1, wherein the synthesized fluorescent carbon dots exhibit strong photoluminescence with a high quantum yield and a significant molar absorption coefficient when excited at an optimal wavelength.
3) The method as claimed in Claim 1, wherein the carbon dots selectively bind to arsenic (III) ions through surface functional groups, resulting in photoluminescence quenching due to energy transfer between the nanocarbons and the metal ions.
4) The method as claimed in Claim 1, wherein the carbon dots exhibit quenching for other heavy metal ions in addition to arsenic (III), with arsenic (III) demonstrating greater quenching efficiency than other metal ions.
5) A fluorescent carbon dot composition produced by the method of Claim 1, wherein the carbon dots feature:

- sulfur and nitrogen doping,
- surface groups comprising oxygen, nitrogen, and sulfur, and
- the ability to selectively sense heavy metals in an aqueous environment through fluorescence quenching.

Documents