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Schematic representation of a quantum dot. QDs are nanocrystals composed of a core of a semiconductor, usually composed of elements from groups II–IV, e.g., CdSe, or groups III–V, e.g., InP. The shell is typically a higher bandgap material such as ZnS. Finally, a capping outer layer such as silica can offer large-surface area for covalently linking to biorecognition molecules such as peptides, antibodies, nucleic acids and small-molecule ligands for further application. The diameter of QDs ranges between 2–10 nm.
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Semiconductor quantum dots (QDs) are nanometre-scale crystals, which have unique photophysical properties, such as size-dependent optical properties, high fluorescence quantum yields, and excellent stability against photobleaching. These properties enable QDs as the promising optical labels for the biological applications, such as multiplexed analy...
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The optical properties of vertical semiconductor nanowires can allow an enhancement of fluorescence from surface-bound fluorophores, a feature proven useful in biosensing. One of the contributing factors to the fluorescence enhancement is thought to be the local increase of the incident excitation light intensity in the vicinity of the nanowire sur...
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... When a current is applied or exposed to light, QD emit light of a certain wavelength, the color they glow depend on their size [as shown in the Figure: 2]. Because of these properties they possess several medical applications such as molecular histopathology, disease detection, and biological imaging [49].Quantum dots (QDs) are semiconductor nanocrystals that, as a result of their small size and quantum confinement phenomena, have unusual optical and electrical capabilities. They are useful in a variety of applications, including ion diagnostics and imaging, because to their characteristics [50].Quantum dots can be utilized as ionsensitive probes or contrast materials for various imaging techniques in the context of ion diagnostics and imaging.The sensitivity of quantum dots to particular ions may be controlled. ...
Nanotechnology is a scientific field focused on studying and manipulating matter at very small scales, ranging from one to one hundred nanometers. This technology allows scientists to develop systems that can be used in biological research. By working with materials at the nano level and exploring their interactions, nanotechnology has led to advancements in creating useful materials, structures, and devices. It has also contributed to the development of concepts such as nanoparticles, nanomaterials, and nanoscale technologies. This technology has the potential to bridge the gap between physics, chemistry, and biology by reshaping our current understanding. In the medical field, nanotechnology-based imaging equipment and methods show great promise in transforming medical diagnosis. These innovative technologies offer new insights into the human body at the cellular and molecular levels by utilizing nanoscale materials and electronics. Nanodiagnostics is an emerging application of nanotechnology that aims to meet the needs of clinical diagnostics. It can significantly enhance testing sensitivity, accuracy, and speed, providing valuable information about the underlying cause and state of diseases.In contemporary medicine, diagnostic imaging is essential for the early identification and accurate diagnosis of a wide range of disorders. Although conventional imaging methods like X-rays, MRIs, CTs, and ultrasounds have been widely used, they have drawbacks in terms of sensitivity, specificity, and the capacity to target certain biomarkers. In order to overcome these difficulties and transform diagnostic imaging, nanotechnology has emerged as a possible answer. This research article examines the tremendous improvements in diagnostic and imaging capabilities provided by nanotechnology over conventional approaches.
... Creating NIR fluorescent probes and band gap engineering Li et al. [29] Fig. 2 Schematic illustration of QDs. Source Ref. [30] with a 6 nm diameter and the compositions CdSxSe1-x/ZnS emit light with various wavelengths simply by changing the composition [29]. Moreover, in line with their chemical components, QDs can also be categorized based on the positioning of their constituents in the periodic table for instance groups II-VI (CdTe, CdSe, and CdS) groups III-V (GaAs, InAs, InP, GaN), and later evolved group IV which is composed of C, Si, and Ge share familiar physical and chemical features, for instance, metalloid nature and semiconducting electrical properties. ...
Over the last decade, quantum dots (QDs), as nanomedicine, are gaining huge importance for their theranostic applications, i.e., in the field of diagnosis and therapeutics. QDs can be explained as colloidal, highly fluorescent, and photo-stable semiconductor-based nanomaterials exhibiting outstanding physical, chemical , optical, and electronic properties and biocompatibility with living systems, highlighting them as promising candidates for an extensive range of biomedical applications , like live cell imaging, and in vivo as well as in vitro imaging, traceable drug delivery, fluorescence-activated cell sorting (FACS), photodynamic therapy, and therapeutic applications (gene delivery for gene therapy). Moreover, their surface properties can also be modified by employing multifarious methods like ligand exchange, surface salinization, and ligand capping or encapsulation. Despite these dazzling properties, the clinical applications of QDs are well underestimated so far. In the current book chapter, we explain different types of QDs, their characteristic properties , and their major biomedical applications in the field of diagnosis and therapy. Furthermore, a brief focus on the prospective directions of research in QDs is also discussed.
... In other words, decreasing the size of QDs or more confining the spatial volume of the materials leads to blue shift (lower wavelength side) of emission or absorption spectra. For the past two decades, due to spectroscopic electro-optical properties, the semiconductor quantum dots have gained significant attention in the research community, as they have potential applications in the biomedical industries (Jin and Hildebrandt, 2012;Shao et al., 2011;Yu, 2008;, bio-sensing (Freeman et al., 2007;Hildebrandt, 2011;Jin and Hildebrandt, 2012;Martynenko et al., 2017;Xing et al., 2009), bio-imaging (Arya et al., 2005;Green, 2004;Jin and Hildebrandt, 2012;Martynenko et al., 2017;Xing et al., 2009), photovoltaic solar cells (Hetsch et al., 2011;Nozik et al., 2010;Raffaelle et al., 2002;Tian and Cao, 2013), quantum information processing (Biolatti et al., 2002;Troiani et al., 2000;Wu et al., 2004), and many optoelectronic devices (Masut et al., 1995;Reithmaier et al., 2006;Skolnick and Mowbray, 2004;. However, high market cost and toxicity associated ...
... As a result, the core and the shell are covered with polymer. Furthermore, QDs are inorganic fluorophores with a low reaction to neighbouring compounds, resulting in increased photostability [14,79]. During synthesis, the structure and size of QDs are affected by temperature, time, and the ligands used. ...
Biomaterials play a vital role in targeting therapeutics. Over the years, several biomaterials have gained wide attention in the treatment and diagnosis of diseases. Scientists are trying to make more personalized treatments for different diseases, as well as discovering novel single agents that can be used for prognosis, medication administration, and keeping track of how a treatment works. Theranostics based on nano-biomaterials have higher sensitivity and specificity for disease management than conventional techniques. This review provides a concise overview of various biomaterials, including carbon-based materials like fullerenes, graphene, carbon nanotubes (CNTs), and carbon nanofibers, and their involvement in theranostics of different diseases. In addition, the involvement of imaging techniques for theranostics applications was overviewed. Theranostics is an emerging strategy that has great potential for enhancing the accuracy and efficacy of medicinal interventions. Despite the presence of obstacles such as disease heterogeneity, toxicity, reproducibility, uniformity, upscaling production, and regulatory hurdles, the field of medical research and development has great promise due to its ability to provide patients with personalised care, facilitate early identification, and enable focused treatment.
... The crystals known as quantum dots glow as a result of quantum confinement effects 68 . There are a number of benefits that quantum dots have over traditional fluorescent dyes. ...
This Review focuses on the pressing global healthcare concerns surrounding the high prevalence of oral carcinoma and its late-stage detection. The World Health Organization (WHO) prioritizes early diagnosis and prevention of oral cancer, emphasizing the significance of timely oral screenings for understanding disease prognosis. Detecting crucial signs and symptoms during initial oral screening significantly enhances patient survival rates. Contributing factors to elevated mortality and morbidity include socioeconomic elements, insufficient public awareness, as well as basic medical shortages. While visual examination is conventionally employed to In the presence of risk factors, keep track of client survival, its clinical utility is limited. To address this, efficient screening tools are needed to differentiate between benign and malignant lesions, providing early information about oral squamous cell carcinoma (OSCC). Optical imaging techniques such as tissue-fluorescence imaging and optical coherence tomography show promise. Oral cancer ranks as the sixth most frequent cancer globally, primarily oral squamous cell carcinoma. Detection methods include comprehensive clinical examinations, costly biochemical tests, and invasive biopsies. Saliva emerges as a noninvasive, promising diagnostic fluid for early oral cancer detection. This Review emphasizes its potential, containing a variety of biomarkers (DNA, RNA, and protein indicators) that help with early diagnosis. Direct contact with oral cancer lesions improves the specificity and sensitivity of saliva for screening. Numerous salivary biomarkers have been found, including defensin-1, P53, and cells (IL-8, IL-1b, and TNF-a). However, further research is needed for clinical validation. Late-stage oral cancer diagnosis contributes to elevated mortality rates. Early detection and treatment remain crucial for improved patient outcomes. Spectroscopy, salivary proteomics, toluidine blue staining, auto fluorescence, brush biopsy, DNA analysis, and biomarkers are a few noninvasive techniques that show potential. Nanotechnology-based detection systems, utilizing nanoparticles, offer highly sensitive and specific diagnostic techniques, potentially revolutionizing oral cancer management.
... In contrast to organic fluorophores, QDs have some unique photo-physical properties [23]. The unique properties of QDs that; they have 20 times as bright and 100 times as stable against photo-bleaching when compared to conventional fluorophores [24,25]. QDs is highly promising fluorescent tags for using in biological applications via significant superiority over classic organic fluorophores. ...
Abstract
The bio-imaging technology is one of the most significant modern applications used in several fields, including early diagnosis
of many illnesses that are most important diseases facing humanity and other vital uses. The primary advancement in
nanotechnology is the creation of innovative fluorescence probes called quantum dots (QDs). The use of molecular tagging
in research, in vivo, and in vitro studies is revolutionized by quantum dots. The application of QD indicates conversion in
natural imaging and photography has demonstrated extraordinary appropriateness in bio-imaging, the discovery of novel
drugs, and delivery of targeted genes, biosensing, photodynamic therapy, and diagnosis. New potential methods of early
cancer detection and treatment management are being researched as a result of the special physical and chemical characteristics
of QD probes. The bio-imaging technique depends on the fluorescent emission of the used materials, which is paired
with living cells that are easy to see it in 3D without any surgical intervention. Therefore, the use of QDs many types
that have unique and appropriate properties for use in that application; In terms of fluorescent emission strength, duration
and luminosity.This review article displays some methods of preparation for QDs nanomaterials and the devices used in
this. In addition, it presentssome of challenges that must be avoided for the possibility of using them in the bio-imaging
field; as toxicity, bio-compatibility, and hydrophilization. It’s reviewed some of the devices that use QDs in bio-imaging
technique, the QDs application in cell analysis-imaging, and QDs application in vivo imaging.
... In contrast to organic fluorophores, QDs have some unique photo-physical properties [23]. The unique properties of QDs that; they have 20 times as bright and 100 times as stable against photo-bleaching when compared to conventional fluorophores [24,25]. QDs is highly promising fluorescent tags for using in biological applications via significant superiority over classic organic fluorophores. ...
The bio-imaging technology is one of the most significant modern applications used in several fields, including early diagnosis of many illnesses that are most important diseases facing humanity and other vital uses. The primary advancement in
nanotechnology is the creation of innovative fluorescence probes called quantum dots (QDs). The use of molecular tagging
in research, in vivo, and in vitro studies is revolutionized by quantum dots. The application of QD indicates conversion in
natural imaging and photography has demonstrated extraordinary appropriateness in bio-imaging, the discovery of novel
drugs, and delivery of targeted genes, biosensing, photodynamic therapy, and diagnosis. New potential methods of early
cancer detection and treatment management are being researched as a result of the special physical and chemical characteristics of QD probes. The bio-imaging technique depends on the fluorescent emission of the used materials, which is paired
with living cells that are easy to see it in 3D without any surgical intervention. Therefore, the use of QDs many types
that have unique and appropriate properties for use in that application; In terms of fluorescent emission strength, duration
and luminosity.This review article displays some methods of preparation for QDs nanomaterials and the devices used in
this. In addition, it presentssome of challenges that must be avoided for the possibility of using them in the bio-imaging
field; as toxicity, bio-compatibility, and hydrophilization. It’s reviewed some of the devices that use QDs in bio-imaging
technique, the QDs application in cell analysis-imaging, and QDs application in vivo imaging
... The observed sizes exhibit a wide range, spanning from one to 10 nm. In contrast to macrocrystalline materials, the distinguishing characteristic of these materials lies in their relatively modest size (Shao et al., 2011). In numerous fields of scientific investigation, QDs possessing unique characteristics have been harnessed for various purposes. ...
Quantum dots (QDs) are a class of remarkable materials that have garnered significant attention since their initial discovery. It is noteworthy to mention that it took approximately a decade for these materials to be successfully implemented in practical applications. While QDs have demonstrated notable optical properties, it is important to note that these attributes alone have not rendered them a feasible substitute for traditional organic dyes. Furthermore, it is worth noting that the substance under investigation exhibited inherent toxicity and instability in its initial state, primarily due to the presence of a heavy metal core. In the initial stages of research, it was observed that the integration of nanocomposites had a positive impact on the properties of QDs. The discovery of these nanocomposites was motivated by the remarkable properties exhibited by biocomposites found in nature. Recent discoveries have shed light on the potential utilization of QDs as a viable strategy for drug delivery, offering a promising avenue to enhance the efficacy of current pharmaceuticals and pave the way for the creation of innovative therapeutic approaches. The primary objective of this review was to elucidate the distinctive characteristics that render QDs highly suitable for utilization as nanocarriers. In this study, we will delve into the multi-faceted applications of QDs as sensing nanoprobes and their utilization in diverse drug delivery systems. The focus of our investigation was directed toward the utilization of QD/polymer composites in sensing applications, with particular emphasis on their potential as chemical sensors, biosensors, and physical sensors.
... Electrostatics of the vertical nanowire metal-insulatorsemiconductor (MIS) structures [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] 3.1. Introduction: From horizontal to vertical device architecture [42] 3.2. ...
... Concerns regarding utilizing conventional 'high-k' technology in nanowire vertical MIS structures to maintain electrostatic integrity [43] 3.3. Analytical modeling of vertical nanowire MIS devices [44] 3.4. Carrier concentration profile and capacitance-voltage (C-V) characteristics of the vertical nanowire MIS device [47] 3.4.1. ...
... Such devices are also integrated in standard CMOS based cameras to improve the sensor performance [38][39][40][41]. Most importantly, the devices have relatively higher photo-to-dark current ratio and faster response time which makes them an inevitable choice for several applications such as, multispectral imaging, spectroscopy, aerospace instruments, health monitoring and thermal imaging [42][43][44][45][46][47][48][49][50][51]. Photovoltaic devices are also expected to experience a 6% to 12% increase of power conversion efficiency by exploiting the properties of quantum dots [52]. ...
The current research work encompasses design modelling and fabrication of vertically aligned nanowire metal oxide semiconductor based voltage tunable quantum dot devices for optoelectronic applications. A novel device scheme is proposed for developing such VTQDs by combining the effects of nanowire geometry dependent structural confinement in transverse directions and the voltage assisted surface quantization in longitudinal direction. The formation of VTQDs near oxide/semiconductor interface at room temperature is predicted by developing a self consistent quantum electrostatic simultaneous solver. The photogeneration phenomenon and carrier transport in nanowire MOS based VTQD devices is analytically modelled by adopting non equilibrium Greens formalism based on second quantization field operators for incident photons and generated photocarriers. Engineering the combined effects of structural and electrical quantization has enabled a route for developing wavelength selective direct colour sensors with high spectral resolution. The developed NEGF based analytical model is further extended to obtain photocurrent which can be utilized for harvesting solar energy. A design window is also proposed for obtaining the desired values of solar cell performance parameters with the optimized device parameters such as, the nanowire diameter and oxide thickness. Finally, a patterned array of such nanowire MOS based VTQD devices is fabricated by employing electron beam lithography. The step like behaviour in capacitance voltage characteristics of such devices measured in situ within the FESEM chamber confirms the formation of VTQDs at room temperature. Such patterned nanowire MOS based VTQD devices can be utilized for the advanced photosensing and solar energy harvesting applications.
... Nanomaterials known as quantum dots possess distinct photophysical characteristics and have been employed in embryo manipulation. Among these, semiconductor quantum dots, which exhibit optical properties contingent upon the size, have been used to label and track embryos during their developmental stages (Shao et al., 2011). Metal chalcogenide quantum dots, another class of quantum dots, have gained significant traction due to their quantum confinement effects and potential applications in biosensing and bioimaging (Mal et al., 2016). ...
Advancements in technology and science have facilitated the development of various materials for use in different industries. These materials can range from large sizes to even nanometer dimensions. Nanomaterials or nanoparticles, which fall within the size range of 1 to 100 nanometers, have emerged as a prominent aspect of nanotechnology. Nanotechnology, known as one of the fastest-growing technologies today, has found applications in a wide array of fields such as health, energy, metallurgy, physics, chemistry, and engineering. Nanomaterials can be produced using diverse methods, including chemical synthesis and the utilization of biological structures. Biocompatible nanomaterials, as they are commonly referred to, have particularly found significance in the medical science, including applications in oncology, tissue engineering, and drug delivery. While certain areas have made remarkable progress in terms of nanobiotechnology, there are other areas that are comparatively new to the realm of nanotechnology. Reproductive biotechnologies are among the fields that are slowly and cautiously exploring the use of nanomaterials. Similar to a baby's crawling, progress in this field is being made gradually, and each day brings forth surprising developments through ongoing studies. In this book, which is prepared for our esteemed readers, the uses of nanotechnology in reproduction have been compiled. It covers various bioengineering studies and explores its functions in embryo manipulation, semen purification, infertility treatments, as well as the effects of different nanomaterials on mammalian semen and aquatic organisms. I would like to express my gratitude to all my colleagues who have contributed to this book, aimed at explaining the applications of nanotechnology in reproductive biotechnologies. With the expectation that it would be beneficial to the scientific community... Assist. Prof. Ali Erdem ÖZTÜRK
