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Fluorescence bioimaging applications of europium-doped strontium aluminate nanoparticles
Fluorescence bioimaging is widely used for physiological studies to visualise intercellular molecular events due to its highly selective, sensitive, and non-destructive nature. However, its application in in vivo live imaging is often limited by the scarcity of biocompatible fluorescent probes possessing optimal properties. Our study focuses on developing europium-based nanoparticles for in vivo bioimaging, especially imaging of plants. Eu-doped strontium aluminate nanoparticles were synthesised through a conventional solid-state reaction. Structural characterisation of samples using XRD confirmed the prevalence of SrAl2O4 as the prominent phase. The FTIR spectrum, SEM and TEM images were recorded for further characterization. Photoluminescence studies showed orange red emission of sample. The antibacterial activity of the nanophosphors was studied, demonstrating no antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. Furthermore, in vitro cytotoxicity studies conducted using Neuro-2A cells showed no indications of cytotoxicity associated with europium doped strontium aluminate nanoparticles. When incorporated into the plant tissue culture medium, these nanoparticles were found to have no effect on seed germination and plant growth, and it demonstrated no phytotoxicity. Imaging studies have shown the uptake of nanoparticles by plants and their subsequent transport through the vascular system. Our results emphasise the direct integration of nanophosphors into plant tissues from the growth medium, eliminating the necessity for traditional staining methods in fluorescence bioimaging. Incorporation of nanophosphors into living organisms holds promise for non-invasive and long-term fluorescence imaging, with potential applications in biological studies and diagnostics. The outstanding fluorescence properties and biocompatibility of europium doped strontium aluminate nanoparticles broaden its potential for various applications in fluorescence bioimaging. 2024 Elsevier Ltd and Techna Group S.r.l. -
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 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 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 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. -
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. -
Food and communities in post-COVID-19 cities: Case of India
While Covid-19 pandemic has affected countries across the world, the burden has been shared disproportionately by urban poor from the cities in Global South. In much of Global South, while cities have emerged as growth centers, they are mostly driven by informalities, belying the image of cities, visualized in the mainstream development economics literature as a place of secured formal jobs that free one from the drudgery of rural life. Covid-19 pandemic has exposed these fault-lines in the cities. India serves as a typical case of such urban-centric growth, with informal workers, predominated by disadvantaged social and religious categories, accounting for 81% of workers in urban space. In cities, migrant in general and seasonal migrants increasingly account for bulk of informal workforce. The lockdown imposed in the wake of Covid-19 pandemic left the community of households reliant on informal works for livelihoods, without any rights and entitlements, which affect their access to food. The review of evidence collected in both primary surveys and macro level data points towards sluggishness in recovery of jobs, which coupled with high food inflation, suggests that access to food continues to be an issue in urban governance. The paper calls for a roadmap entailing both short-term and long-term measures to build sustainable urban livelihoods for ensuring food secure urban space in India. 2023 The Author(s) -
Food calorie estimation using convolutional neural network
The modern world healthy body depends on the number of calories consumed, hence monitoring calorie intake is necessary to maintain good health. At the point when your Body Mass Index is somewhere in between from 25 to 29. It implies that you are conveying overabundance weight. Assuming your BMI is more than 30, it implies you have obesity. To get in shape or keep up the solid weight individuals needs to monitor the calorie they take. The existing system calorie estimation is to be happened manually. The proposed model is to provide unique solution for measuring calorie by using deep learning algorithm. The food calorie calculation is very important in medical field. Because this food calorie is provide good health condition. This measurement is taken from food image in different objects that is fruits and vegetables. This measurement is taken with the help of neural network. The tensor flow is one of the best methods to classify the machine learning method. This method is implementing to calculate the food calorie with the help of Convolutional Neural Network. The input of this calculated model is taken an image of food. The food calorie value is calculated the proposed CNN model with the help of food object detection. The primary parameter of the result is taken by volume error estimation and secondary parameter is calorie error estimation. The volume error estimation is gradually reduced by 20%. That indicates the proposed CNN model is providing higher accuracy level compare to existing model. 2021 IEEE. -
Food Detection and Recognition Using Deep Learning - A Review
Studies show poor lifestyle choices and unhealthy eating patterns cause issues like obesity and other ongoing illnesses that raise the risk of heart attacks, such as hypertension, abnormal blood sugar levels, and diabetes. To improve this situation a lot of health apps have been built which use modern dietary monitoring systems that automatically evaluate dietary intake using machine learning and deep learning techniques rather. For these reasons indepth investigations on food detection, classification, and analysis have been conducted. Some of the top methods for automatic food recognition created have been discussed in this paper. We also propose an idea for detection of Indian food items using image classification. According to our findings of the papers we reviewed, convolutional neural networks (CNN) have been extensively been used in food detection as it has been giving better results compared to other models. We also observed that Vision transformers perform better in situations where the dataset is large and a hybrid model would give better accuracy. A review of potential applications for food image analysis, shortfalls in the area, and open issues concludes the paper. 2022 IEEE. -
Food innovation adoption and organic food consumerism-a cross national study between Malaysia and Hungary
In order to meet the rising global demand for food and to ensure food security in line with the United Nations Sustainable Development Goal 2, technological advances have been introduced in the food production industry. The organic food industry has benefitted from advances in food technology and innovation. However, there remains skepticism regarding organic foods on the part of consumers, specifically on consumers acceptance of food innovation technologies used in the production of organic foods. This study measured factors that influence consumers food innovation adoption and subsequently their intention to purchase organic foods. We compared the organic foods purchase behavior of Malaysian and Hungarian consumers to examine differences between Asian and European consumers. The findings show food innovation adoption as the most crucial predictor for the intention to purchase organic foods in Hungary, while social lifestyle factor was the most influential in Malaysia. Other factors such as environmental concerns and health consciousness were also examined in relation to food innovation adoption and organic food consumerism. This paper discusses differences between European and Asian organic foods consumers and provides recommendations for stakeholders. 2021 by the authors. Licensee MDPI, Basel, Switzerland.