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Fluorescent carbon nanoparticle hybrids: synthesis, properties and applications
The development of materials in nanoscale morphologies with novel compositions is one of the major focuses of nanoscience and technology, as these materials are imbibed with unique properties that make them suitable for specific applications in a large variety of fields. Combining two or more chemically distinct constituents into a single nanostructure helps to attain desirable attributes of physical and chemical responses that can be efficiently utilized for specific applications. Hybrid nanomaterials constituted as a combination of multiple components into single nanostructures are known to showcase the properties of the individual components in tandem or synergy. Novel functionalities are also known to arise from integrating Fluorescent carbon nanoparticles (FCNPs) with other counterparts. FCNPs, when combined with other materials to form nanohybrids, provide copious functional attributes due to their inherent properties and the augmentation in properties due to the presence of the other materials. Integrating hybrid counterparts with FCNs improves the functional properties, which can be utilized for various applications such as photocatalysis, bioimaging, bio/chemo sensing, and many more. Herein we present an overview of recent and relevant works related to the synthesis, properties, and applications of fluorescent carbon nanoparticle (FCNP) hybrids. Various synthetic routes of FCNP hybrids via physical and chemical methods are summarized. The properties of the hybrid systems and the influence of hybridization on the properties are discussed. Applications of FCNP hybrids in various fields are also discussed in detail. 2025 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies. -
Fluorescent carbon nanoparticles for catalytic and photocatalytic applications
In the present times, catalysis is ubiquitous in chemical processes. Catalysts range from macromolecules consisting of enzymes to nanoparticles, including metals/metal oxides and composite materials. Due to their harmlessness, biocompatibility, high stability, versatility, and ease of functionalization, carbon nanomaterials (CNMs) which are fluorescent in nature, are used extensively for catalytic applications. Several studies regarding the catalytic applications of CNMs have been reported. These applications range from homogeneous to heterogeneous catalysis, where CNMs are used as supports for metal/metal oxide nanoparticles. Extensive studies on nanocomposites, doping strategies, and their utility in catalysis have been carried out. Carbon-based electrocatalysts find applications in both storage and conservation of energy. The exceptional properties of these materials make them an apt choice for various environment-friendly organic transformations. Photocatalysis is another area in which CNMs have excelled. Photoluminescence, photostability, and electron transfer properties of CNMs make them potent candidates for several photoinduced reactions. Various CNMs, namely graphene, carbon dots, nanotubes, graphitic carbon nitride, fullerenes, and graphdiyne, find applications in medicine, catalysis, sensing, bioimaging, supercapacitors, and many more. This chapter focuses on the catalytic and photocatalytic applications of CNMs. 2025 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies. -
Fluorescent Carbonized Polymer Dots Derived from o-phenylenediamine and its Photonic Application
Optimizing the optoelectronic characteristics of low-dimensional carbon dots (CDs) through surface modifications and doping has proven instrumental in tailoring them for diverse applications. This study explores a facile and economical hydrothermal synthesis method for generating Carbonized Polymer Dots using o-phenylenediamine at different temperatures. The resulting materials exhibit structural and morphological variations linked to the synthesis temperature. A transition from carbon dots (CDs) embedded in reduced graphene oxide (rGO)-like sheet structures at low temperatures to the core-shell structure at the highest temperature is observed in HR-TEM, implying the formation of CPDs. X-ray photoelectron spectroscopy (XPS) corroborates these findings, showing an augmented degree of graphitization in alignment with HR-TEM results. The photoluminescence spectra of CPDs synthesized at the lowest temperature exhibit multiple emission peaks, resulting in a yellowish-orange color. Utilizing these CPDs to fabricate light-emitting diodes (LEDs) produces a vivid bright-green emission with CIE coordinates (0.378, 0.522). Moreover, the CPDs demonstrate solvatochromism across diverse solvents of varying polarity, covering the entire visible spectrum. This intriguing solvatochromic effect positions the CPDs as promising materials for polarity probing applications. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Fluorescent Carbonized Polymer Dots Derived from o-phenylenediamine and its Photonic Application
Optimizing the optoelectronic characteristics of low-dimensional carbon dots (CDs) through surface modifications and doping has proven instrumental in tailoring them for diverse applications. This study explores a facile and economical hydrothermal synthesis method for generating Carbonized Polymer Dots using o-phenylenediamine at different temperatures. The resulting materials exhibit structural and morphological variations linked to the synthesis temperature. A transition from carbon dots (CDs) embedded in reduced graphene oxide (rGO)-like sheet structures at low temperatures to the core-shell structure at the highest temperature is observed in HR-TEM, implying the formation of CPDs. X-ray photoelectron spectroscopy (XPS) corroborates these findings, showing an augmented degree of graphitization in alignment with HR-TEM results. The photoluminescence spectra of CPDs synthesized at the lowest temperature exhibit multiple emission peaks, resulting in a yellowish-orange color. Utilizing these CPDs to fabricate light-emitting diodes (LEDs) produces a vivid bright-green emission with CIE coordinates (0.378, 0.522). Moreover, the CPDs demonstrate solvatochromism across diverse solvents of varying polarity, covering the entire visible spectrum. This intriguing solvatochromic effect positions the CPDs as promising materials for polarity probing applications. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Fluorescent chiral nematogens derived from naturally occurring moieties
We discuss the synthesis and characterisation of new non-symmetric liquid crystal dimers of cholesteryl n-(4-formyl-2-methoxyphenoxy)alkanoates by tethering cholesterol and vanillin. Spectroscopic characterisation such as IR, 1H and 13C NMR used to confirm the molecular structures. Mesophase properties are assessed using polarising optical microscopy (POM) and differentially scanning calorimeter (DSC). All the dimers in the series display liquid crystalline phase particularly cholesteric and smectic A* phases. Additionally, a UV-Vis study showed that the molecules self-assemble into H-aggregates with strong fluorescence emission. DFT studies provide insights into molecular geometry, electronic structure, and energy states, enabling detailed estimations of chemical behaviour and interactions. 2025 Informa UK Limited, trading as Taylor & Francis Group. -
Fluorescent detection of Pb2+ pollutant in water samples with the help of Delonix regia leaf-derived CQDs
Heavy metals released from different sources into water bodies are a major concern in the view of environmental protection. Their non-biodegradability and the numerous health hazards add to the issue. Scientists worldwide have emphasized the issue and are trying to resolve it by different means. Among all the methods, the fluorescent method stands out for its simplicity and rapid results. Here, the study focuses on the development of an efficient and sustainable method for the detection of lead in waste-water effluents. Carbon quantum dots (GCDs), a highly non-toxic substance developed from Delonix regia leaves for the purpose via a simple hydrothermal method. The prepared GCDs exhibited good photostability and water solubility; they also displayed a bright red emission when irradiated with ultraviolet (UV) light. Here, the authors propose the synthesized GCDs as an effective fluorescent probe for sensitive detection of lead ions in aqueous samples. Photoluminescence quenching of GCDs by the addition of lead was studied and a good detection limit of 3.3 nM with a linear range of 10180 M was achieved. Further, real sample analysis was also conducted to prove the applicability of the synthesized GCDs. 2022 Elsevier B.V. -
Fluorescent detection of Pb2+ pollutant in water samples with the help of Delonix regia leaf-derived CQDs /
Synthetic Metals, Vol.291, ISSN No: 0379-6779.
Heavy metals released from different sources into water bodies are a major concern in the view of environmental protection. Their non-biodegradability and the numerous health hazards add to the issue. Scientists worldwide have emphasized the issue and are trying to resolve it by different means. Among all the methods, the fluorescent method stands out for its simplicity and rapid results. Here, the study focuses on the development of an efficient and sustainable method for the detection of lead in waste-water effluents. Carbon quantum dots (GCDs), a highly non-toxic substance developed from <em>Delonix regia</em> leaves for the purpose via a simple hydrothermal method. -
Fluorescent enhancement of polymer nanoparticle by composite preparation with ruta graveolens nano-carbon and its application in fluorescence sensing /
Patent Number: 202241039689, Applicant: Neethu Joseph.
The current invention provides an environmentally friendly, green synthesis of a cost- effective and scalable nanocarbon-polymer composite with possible fluorescence features that may be used in fluorescence sensing. The fluorescence of the produced nanostructure is high, indicating that this could be employed in fluorescence-based sensing applications. Fluorescence spectroscopy experiments show that the produced nano-carbon has remarkable heavy metal ion sensing potential. -
Fluorescent imidazole derived sensor for selective in vitro and in vivo Fe2+ detection and bioimaging in zebrafish with DFT studies
Herein, we have developed imidazole derivatized fluorescent probes IM-1 and IM-2 for extremely selective detection of Fe2+ with rapid response (LOD: 3.245 ?M for IM-1 and 0.297 ?M for IM-2) and excellent binding constants (0.214 105 M?1 and 1.004 105 M?1). Aqueous ethanol system was employed to assess the sensing potency of the probes both in vitro and in vivo in zebrafish is the main highlight of this work. The synthesized fluorophores possess admirable quantum yields of 0.61 and 0.78. The 1:1 binding mechanism of ligands with Fe2+ ions is supported by Job's plot and ESI-Mass spectrum. The synthesized probes demonstrated limited cytotoxicity both in vitro (MDA-MB-231 cells) and in vivo (zebrafish, Danio Rerio) studies. These results prompted us to employ the probes IM-1 and IM-2 to trace out intra cellular Fe2+ ions in zebrafish embryos. 2024 Elsevier B.V. -
Fluorescent Mechanism in Zero-Dimensional Carbon Nanomaterials: A Review
Fluorescent carbon dots (CDs) have acquired growing interest from different areas over decades. Their fascinating property of tunable fluorescence by changing the excitation wavelength has attracted researchers worldwide. Understanding the mechanisms behind fluorescence is of great importance, as they help with the synthesis and applications, significantly when narrowed down to applications with color-tunable mechanisms. But, due to a lack of practical and theoretical information, the fluorescence mechanisms of CDs remain unknown, preventing the production of CDs with desired optical qualities. This review focuses on the PL mechanisms of carbon dots. The quantum confinement effect determined the carbon core, the surface and edge states determined by various surface defects and the connected functional/chemical groups on the surface/edges, the molecular state solely determined the fluorophores in the interior or surface of the CDs, and the Crosslink Enhanced Emission Effect are the currently confirmed PL mechanisms. Graphic Abstract: [Figure not available: see fulltext.]. 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Fluorescent nanocellulose derived from Plectranthus barbatus for the selective detection of Pb(ii) ions in aqueous solutions
This study reports the synthesis of fluorescent nanocellulose from Plectranthus barbatus and its effective use as a fluorescent probe for the detection of Pb(ii) ions in aqueous solutions. Nanocellulose, a nanoscale derivative of cellulose, is used in a variety of applications, such as sensing, food packaging, and biomedical applications, owing to its characteristic properties. In sensing applications, it is mostly used as a support or substrate for the sensing probe. Nanocellulose shows intrinsic fluorescence, which can be harnessed for sensing applications. This underexplored research domain holds significant potential for developing sustainable and cost-effective sensing materials. We synthesized nanocellulose from Plectranthus barbatus (PBNC) and employed it as a fluorescent probe for the detection of Pb(ii). To the best of our knowledge, this is the first report demonstrating the potential of fluorescent nanocellulose for metal ion detection. The properties of fluorescent nanocellulose, PBNC, were studied using Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Photoluminescence (PL) spectroscopy. The fluorescence intensity of the nanocellulose was remarkably quenched in the presence of Pb(ii) ions selectively. The detection limit (LOD) of Pb(ii) using PBNC was found to be 2.7 nM. PBNC is a novel autofluorescent material that functions as an efficient nanosensor for the detection of Pb(ii) ions, and its applications can be extended to bio-imaging and sensing in biological, chemical, and environmental samples. This journal is The Royal Society of Chemistry, 2026. -
Fluorescent Photosensitizers: A Promising Tool for Biomedicine
The growing demand for the detection for biomedical imaging has taken the interest of researchers as there is a significant increase in cancer and malignant diseases across the globe. Photosensitizers assisted with fluorescent properties can be a pioneer in this field. Photosensitizers generally damage the living cell, however, selected fluorescent photosensitizers can offer a minimal threat to the living cells. Medically relevant processes such as live cell imaging and photodynamic therapy can be monitored using this technique. Some of the commonly used fluorescent photosensitizers include porphyrins, chlorins, and bacteriochlorins. This chapter addresses the significance, limitations, and future perspectives of fluorescent photosensitizers in biological applications. Scientists can develop efficient fluorescent photosensitizers for easy detection and cure of different infectious diseases. The chapter also puts forward a deeper understanding of the principle underlying tunable fluorescent properties, and the recent efforts for developing efficient fluorescent photosensitizers. 2022 Nova Science Publishers, Inc. -
Fluorescent PVDF dots: from synthesis to biocidal activity
Infection by microorganisms is a serious concern in food storage, water purification, drugs, and particularly in biomedical devices. Long-term use of permanent implants often leads to its contamination due to pathogens. Timely tracking of bacterial activity and its interaction with antibodies are crucial for overcoming these infections. In this work, fluorescent polymeric biocides are obtained from a non-conjugated polymer polyvinylidene fluoride (PVDF), which is neither emissive nor known for its antibacterial activity. PVDF dot was synthesized via hydrothermal treatment eliminating the need for complicated and toxic preparation strategies. PVDF-based dot exhibits high fluorescence aroused from the carbogenic core due to the carbonization of the hydrocarbon chain. It is found that the dots were semiconducting contrary to the bulk form of PVDF. The photoluminescent polymer dots also exhibited an excellent antibacterial activity toward Escherichia coli (E.coli) and Streptococcus bacteria. This luminescence and biocidal activity of PVDF-derived dots have attractive applications in the field of fluorescent diagnostics and therapeutics. Graphical abstract: [Figure not available: see fulltext.] 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. -
Fluorogenic selective detection of Zn2+ using a pyrazole-ortho-vanillin conjugate: insights from DFT, molecular docking, bioimaging and anticancer applications
A fluorescent sensor, (E)-N?-(2-hydroxy-3-methoxybenzylidene)-3,5-dimethyl-1H-pyrazole-1-carbohydrazide (HMPC), was designed and synthesized for the selective fluorescence recognition of Zn2+ in semi-aqueous media. Notably, HMPC exhibited a red-shifted, two-fold fluorescence turn-on enhancement in response to Zn2+ at 490 nm, with a detection limit of 1.68 ?M, which is significantly lower than the WHO guideline (76.0 ?M). The binding constant of HMPC with Zn2+ was calculated to be 5 104 M?1. The fluorescence enhancement of HMPC in the presence of Zn2+ is attributed to the suppression of the PET process and the enhancement of ICT, leading to fluorescence via the CHEF mechanism. The sensing mechanism was demonstrated through UV-vis, fluorescence spectroscopy, Job plots, ESI-MS, and DFT calculations. For biological applications, cytotoxicity and cell imaging studies were performed using MCF-7 cells. Molecular docking studies revealed a high binding energy of HMPC (?G = ?7.1 kcal mol?1) with the 4,5-diaryl isoxazole HSP90 chaperone protein, suggesting its potential as an anticancer agent. Additionally, its binding energy of ?6.5 kcal mol?1 with the HDAC8 protein indicates greater efficacy than suberoylanilide hydroxamic acid (SAHA) in inhibiting HDAC, as it binds more strongly to the HDAC8 protein than SAHA (?7.4 kcal mol?1). Furthermore, due to its favorable ADME profile, HMPC may be suitable for oral administration, enhancing its potential as an anticancer drug. 2025 The Royal Society of Chemistry. -
FO-DPSO Algorithm for Segmentation and Detection of Diabetic Mellitus for Ulcers
In recent days, the major concern for diabetic patients is foot ulcers. According to the survey, among 15 people among 100 are suffering from this foot ulcer. The wound or ulcer found which is found in diabetic patients consumes more time to heal, also required more conscious treatment. Foot ulcers may lead to deleterious danger condition and also may be the cause for loss of limb. By understanding this grim condition, this paper proposes Fractional-Order Darwinian Particle Swarm Optimization (FO-DPSO) technique for analyzing foot ulcer 2D color images. This paper deals with standard image processing, i.e. efficient segmentation using FO-DPSO algorithm and extracting textural features using Gray Level Co-occurrence Matrix (GLCM) technique. The whole effort projected results as accuracy of 91.2%, sensitivity of 100% and specificity as 96.7% for Nae Bayes classifier and accuracy of 91.2%, sensitivity of 100% and sensitivity of 79.6% for Hoeffding tree classifier. 2023 World Scientific Publishing Company. -
Foetal brain extraction using mathematically modelled local foetal minima
This paper proposes segmentation techniques to separate brain parcel from the MRI of the human embryo and also determines the abnormality of the foetal brain at various gestational weeks. These strategies mean to characterise areas of the premium of various granularities: brain, tissue types, or constructions that are more limited. Various philosophies have been applied for this division task and can be grouped into the solo, parametric, characterisation, atlas combination, and deformable models. Brain atlases are usually used as preparing information in the division interaction. Difficulties identifying using pictures secured, the quick mental health, and the restricted accessibility of imaging information thwart this division task. This paper discusses foetal brain segmentation using mathematically modelled foetal brain minima by using a curve fitting segmentation technique. Broad tests show that the proposed approach beats the ebb and flow of various segmentation techniques and the results gained are significant. Copyright 2023 Inderscience Enterprises Ltd. -
Folic Acid-Modified B-Type Y2O3:Eu3+ Quantum Dots: A Bright Approach to Fluorescence Imaging of Cancer Cells
Clinical applications of nanophosphors have gained extensive interest in research areas such as bioimaging and targeted drug delivery. The development of nontoxic semiconductor quantum dots (QDs), which can replace the conventional fluorescent probes, can bring significant developments in the bioimaging industry. This work reports the synthesis of monoclinic Y2O3:Eu QDs, without and with surface functionalization using PEG/folic acid at low temperature and its application in live cancer cell imaging. The synthesized quantum dots show sharp absorption in the short UV region and an intense red emission at 614 nm. Concentration-dependent optical properties are studied in detail, and color purity is measured. Transmission electron microscopy substantiates the monoclinic structure, crystalline nature, and the lower particle dimensions essential for the biological applications. The surface-modified sample is characterized for its structural and luminescence properties. Biocompatibility was ensured by performing MTT Assay on L6 skeletal muscle cell lines (normal) and MCF 7 cell lines (cancer) for the samples without and with surface modification, respectively. Fluorescence detection experiments on SKMEL cells using an uncapped sample prove the suitability of the material as a fluorescent probe. The effect of surface functionalization on imaging results was established by carrying out fluorescence detection experiments on MCF 7 cells using PEG-folic acid-functionalized sample, which resulted in enhanced cell uptake, specific binding, and bright fluorescence emission. Thus, this work authenticates the suitability of the material to be used as a reliable nanophosphor and an efficient fluorescent probe for imaging cancer cells. 2024 American Chemical Society. -
Folksonomy-based fuzzy user profiling for improved recommendations
Genre is a major factor influencing user decisions to peruse an item in domains such as movies, books etc. Recommender systems, generally have, at their disposal, information regarding genres/categories that a movie/book belongs to. However, the degree of membership of the objects in these categories is typically unavailable. Such information, if available, would provide a better description of items and consequently lead to quality recommendations. In this paper, we propose an approach to infer the degree of genre presence in a movie by examining the various tags conferred on them by various users. Tags are user-defined metadata for items and embed abundant information about various facets of user likes, their opinion on the quality and the type of object tagged. Leveraging on tags to guide the genre degree determination exploits crowd sourcing to enrich item content description. Fuzzy logic naturally models human logic allowing for the nuanced representation of features of objects and thus is utilized to derive such gradual representation as well as for modeling user profiles. To the best of our knowledge ours is one of the first approaches to utilize such folksonomy information to infer genre degrees subsequently used for recommendations. The proposed method has the twin advantages of utilizing enriched content information for recommendation as well as squeezing the information from the user-item-tag and user-item ratings spaces and condensing them into fuzzy user profiles. The fuzzy user and object representations are leveraged both for the design of content-based as well as collaborative recommender systems. Experimental evaluations establish the effectiveness of the proposed approaches as compared to other baselines. 2013 Elsevier Ltd. All rights reserved. -
Food additives and contaminants in infant foods: a critical review of their health risk, trends and recent developments
The infant food market has expanded rapidly over the past two decades. However, the industry faces significant challenges, including concerns over the health effects of infant food additives and issues with food safety. However, new evidences suggest that certain food additives, such as those used to preserve and transport infant formula to keep it fresh for longer, should be avoided. Science into the effects of additives on human behavior makes up a sizable sector of the additives market. Problems such as hypernatremic dehydration, malnutrition, and obesity in infants are directly linked to faulty formula production. The Food and Drug Administration (FDA) has established the toxicity types and chemical tests necessary for evaluating the safety of food additives and GRAS (Generally Recognized as Safe) compounds. These tests are crucial in understanding the food safety aspects of food additives. The health effects of different types of food additives on infants are discussed in this context. The article gives an outline of various national and global agencies that provides recommendations and standards to gauge the quality of baby food. The immunological responses, allergic reaction pathways and other related health hazards among the infants and young children caused by the food additive are discussed in this article. Graphical Abstract: (Figure presented.) The Author(s) 2024. -
Food Additives and Evolved Methods of Detection: A Review
Food additives are essential constituents of food products in the modern world. The necessity of food processing went up rapidly as to meet requirements including, imparting desirable properties like preservation, enhancement and regulation of color and taste. The methods of identification and analysis of such substances are crucial. With the advancement of technology, a variety of techniques are emerging for this purpose which have many advantages over the existing conventional ways. This review is on different kinds of additives used in the food industry and few prominent methods for their determination ranging from conventional chromatographic techniques to the recently evolved nano-sensor techniques. 2024 Taylor & Francis Group, LLC.