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![a) Schematic illustration of rationally design of biomolecular templates for the synthesis of metal nanoclusters [17], b) Different strategies for improvement of ligand-to-metal charge transfer in ligand-protected metal nanoclusters [46].](publication/344678527/figure/fig1/AS:961196635217921@1606178544127/a-Schematic-illustration-of-rationally-design-of-biomolecular-templates-for-the.png)
a) Schematic illustration of rationally design of biomolecular templates for the synthesis of metal nanoclusters [17], b) Different strategies for improvement of ligand-to-metal charge transfer in ligand-protected metal nanoclusters [46].
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Noble metal nanoparticles (NPs) such as gold and silver, in the size range of 5-100 nm possess unique plasmonic properties such as light scattering and absorption, which can be altered by changing their shape, size, chemical composition, and even the dielectric constant of the medium; while the ultrasmall metal nanoclusters (NCs) with size less tha...
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Context 1
... of M À S bond (i.e., M ¼ Au, Ag, Cu, etc.) at the outer layer of metal NCs. In addition, biotemplated approach has also received paramount attention due to the use of green synthesis conditions (e.g., aqueous solution) and biomolecular ligands leading to the formation of biocompatible metal NCs, which is an advantage for biomedical applications (Fig. 2a). For example, we have employed natural proteins as biotemplates to synthesize the bovine-serum albumin (BSA)-protected silver nanoclusters (BSA-AgNCs) [38] and human serum albumin (HSA)-protected gold nanoclusters (HSA-AuNCs) [39] respectively with special functionalities such as high fluorescence for bioimaging/sensing and singlet ...
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... the fluorescence intensity of as-synthesized metal nanoclusters. The first method is ligand engineering with preservation of metal NC structure. In this approach, the ligand-to-metal charge transfer (LMCT) process can be controlled using ligands with different electron-donating ability or change in the electron-withdrawing ability of metal kernel (Fig. 2b). For example, Wu and Jin [41] observed the enhanced fluorescence with increasing electron donating ability of the ligand in the synthesis of Au nanocluster, where Au 25 (SC 6 H 13 ) 18 < Au 25 (SC 12 H 25 ) 18 < Au 25 (SC 2 H 4 Ph) 18 . The second method is ligand engineering with transformation of metal NC structure. Briefly, the ...
Citations
... Plasmonic metal nanoparticles have become important in biosensing as a result of advancements in nanofabrication techniques. Various platforms for bacteria detection could be developed using metallic nanoparticles, such as colorimetric and fluorescent detection platforms [80]. Among the metallic nanoparticles, gold nanoparticles (AuNPs) are the most widely utilized for colorimetric detection due to various advantages such as controlled synthesis, excellent solubility, and easy surface modification [81]. ...
Sepsis is a critical disease caused by the abrupt increase of bacteria in human blood, which subsequently causes a cytokine storm. Early identification of bacteria is critical to treating a patient with proper antibiotics to avoid sepsis. However, conventional culture-based identification takes a long time. Polymerase chain reaction (PCR) is not so successful because of the complexity and similarity in the genome sequence of some bacterial species, making it difficult to design primers and thus less suitable for rapid bacterial identification. To address these issues, several new technologies have been developed. Recent advances in nanotechnology have shown great potential for fast and accurate bacterial identification. The most promising strategy in nanotechnology involves the use of nanoparticles, which has led to the advancement of highly specific and sensitive biosensors capable of detecting and identifying bacteria even at low concentrations in very little time. The primary drawback of conventional antibiotics is the potential for antimicrobial resistance, which can lead to the development of superbacteria, making them difficult to treat. The incorporation of diverse nanomaterials and designs of nanomaterials has been utilized to kill bacteria efficiently. Nanomaterials with distinct physicochemical properties, such as optical and magnetic properties, including plasmonic and magnetic nanoparticles, have been extensively studied for their potential to efficiently kill bacteria. In this review, we are emphasizing the recent advances in nano-biotechnologies for bacterial identification and anti-bacterial properties. The basic principles of new technologies, as well as their future challenges, have been discussed.
... Optics-based sensing applications depend upon the changes created in the photophysical properties. The advancement of nanotechnology and nanoscience has resulted in the development of nano spectrometric biosensing devices like "dynamic light scattering sensors" [16], Raman scattering sensors [17,18], electro-chemiluminescence sensors [19], fluorescent sensors [20], colorimetric sensors [21], Kretschmann configuration-based sensor models [22,23], and surface plasmon resonance sensors [24][25][26][27][28]. These sensors used fundamental optical principles but simultaneously showed unique advantages by combining optics with nanomaterials [29][30][31][32]. ...
This work showcases a novel optical setup for water sensing based on transmission (Tx) (%) and absorbance (Ab) (AU). Four different water samples examine the sensing ability of the proposed device. These samples consist of RO water, tap water, groundwater, and pond water. The setup details the Tx (%) and Ab (AU) from different water samples. The Tx (%) obtained from the RO water (RW), tap water (TW), groundwater (GW), and pond water (PW) are 51.71%, 49.63%, 47.24%, and 45.92%, respectively. Similarly, the water sample’s Ab (AU) is 0.288 AU, 0.297 AU, 0.320 AU, and 0.336 AU, corresponding to RW, TW, GW, and PW respectively. A linear relationship between Tx (%) and wavelength reaching the degree (2) provides maximum R² = 0.9313. Similarly, a linear relationship between Ab (AU) and wavelength corresponding to a degree (2) provides maximum R² = 0.9999. Thus, the developed setup successfully provides information about the sensing features from different water samples.
... Colorimetric methods provide visual recognition for aptamer-target binding, which is either discerned with the naked eye or measured quantitatively using an optical reader. The concentration of the detected targets is determined by any alterations in scattering and absorption efficiencies [94], the refractive index of the surrounding medium [94], the electromagnetic spectrum [95] or wavelength, and the full width at half maximum (FWHM) values of the resonance signal [96]. Such methods hold great potential for on-site diagnosis, especially in resource-limited settings, since they are cost-effective and straightforward [97]. ...
... Colorimetric methods provide visual recognition for aptamer-target binding, which is either discerned with the naked eye or measured quantitatively using an optical reader. The concentration of the detected targets is determined by any alterations in scattering and absorption efficiencies [94], the refractive index of the surrounding medium [94], the electromagnetic spectrum [95] or wavelength, and the full width at half maximum (FWHM) values of the resonance signal [96]. Such methods hold great potential for on-site diagnosis, especially in resource-limited settings, since they are cost-effective and straightforward [97]. ...
Recent innovations in point-of-care (POC) diagnostic technologies have paved a critical road for the improved application of biomedicine through the deployment of accurate and affordable programs into resource-scarce settings. The utilization of antibodies as a bio-recognition element in POC devices is currently limited due to obstacles associated with cost and production, impeding its widespread adoption. One promising alternative, on the other hand, is aptamer integration, i.e., short sequences of single-stranded DNA and RNA structures. The advantageous properties of these molecules are as follows: small molecular size, amenability to chemical modification, low- or nonimmunogenic characteristics, and their reproducibility within a short generation time. The utilization of these aforementioned features is critical in developing sensitive and portable POC systems. Furthermore, the deficiencies related to past experimental efforts to improve biosensor schematics, including the design of biorecognition elements, can be tackled with the integration of computational tools. These complementary tools enable the prediction of the reliability and functionality of the molecular structure of aptamers. In this review, we have overviewed the usage of aptamers in the development of novel and portable POC devices, in addition to highlighting the insights that simulations and other computational methods can provide into the use of aptamer modeling for POC integration.
... Recently, to enhance the performance of biosensors, researchers developed various plasmonic phenomena including propagating surface plasmon resonance (SPR) [28], localized SPR (LSPR) [29], and surface-enhanced Raman scattering (SERS) [30,31]. Usually, the bimetallic structures consisting of gold-silver alloy or gold-aluminum alloy films are considered to enhance the potential of the sensing layer [32]. LSPR sensors are compact, cheaper, less prone to mechanical noise, and more used for the detection of low molecular weight and low-concentration analytes [33]. ...
... In particular, to perform biological measurements using those materials, confirmation of the size, shape, and optical properties of MNPs has been suggested since toxicity is dependent on those parameters [39]. Notably, Fe 2 O 3 and Ag nanostructures with a size range of 20-60 nm are used to design biocompatible plasmonic materials to improve light absorption ability [32]. In addition, Lung cancer is a cancer type that starts in the lungs such as the bronchioles and alveoli. ...
Applying quantum technology to dispatch face-to-face medical activities has generated significant interest. Unfortunately, the work on remote medical treatment soliciting quantum medication and information processing techniques is hard to observe. In this research, we proposed the Mach–Zehnder interferometer (MZI) based optoplasmonic biosensors (OPBs) with two homodyne detectors for remotebased lung cancer detection using classical and quantum mechanical principles. From the classical
basis (Drude-Lorentz model and Kretschmann configuration), the influence of silver nanoparticles
(Ag NPs) layers and biomolecule concentration on the performance of biosensors has been investigated. The different types of cancer cells for CL1-5, A549, and HT-29 have been used to analyze
the sensitivity, and 319, 332, and 365 (deg/RIU) have been achieved, respectively. In addition, from
quantum mechanical principles, the biosignals were conveyed through quantum teleportation in the
form of the quantum state of light via fiber optics cable to enable precise remote detection of lung
cancer. The obtained sensitivity and teleportation fidelity clearly reveal, the best candidacy of the
proposed optoplasmonic biosensor for lung cancer telediagnosis.
... Pathogen detection has been carried out using DLS, in which the pathogens are considered microparticles. Different pathogens exhibit unique scattering of light based on different sizes, shapes, and characteristics of the microbes [87][88][89][90][91]. ...
Detection of foodborne pathogens at an early stage is very important to control food quality and improve medical response. Rapid detection of foodborne pathogens with high sensitivity and specificity is becoming an urgent requirement in health safety, medical diagnostics, environmental safety, and controlling food quality. Despite the existing bacterial detection methods being reliable and widely used, these methods are time-consuming, expensive, and cumbersome. Therefore, researchers are trying to find new methods by integrating spectroscopy techniques with artificial intelligence and advanced materials. Within this progress report, advances in the detection of foodborne pathogens using spectroscopy techniques are discussed. This paper presents an overview of the progress and application of spectroscopy techniques for the detection of foodborne pathogens, particularly new trends in the past few years, including surface-enhanced Raman spectroscopy, surface plasmon resonance, fluorescence spectroscopy, multiangle laser light scattering, and imaging analysis. In addition, the applications of artificial intelligence, microfluidics, smartphone-based techniques, and advanced materials related to spectroscopy for the detection of bacterial pathogens are discussed. Finally, we conclude and discuss possible research prospects in aspects of spectroscopy techniques for the identification and classification of pathogens.
... For Brownian motion situations, the particle size estimate is correlated with the motion, with small particles moving faster and large particles moving slower [166]. If the particles are assumed to be spherically symmetrical and not permeable to the solvent, the Stokes-Einstein equation is used to calculate their hydrodynamic diameter [167]. ...
Given the great relevance that adsorption processes have for many applications, especially for the water and wastewater treatment, the development and improvement adsorbent materials is a key research topic. When a new adsorbent is proposed, a good characterization of the material is fundamental to in order to know its properties, support its application and understand its performance in the desired process. There is a variety of physical and chemical information that can obtained by different techniques, whose choice depends on the type of material to be studied and on the available instrumentation. The available techniques include UV-Vis, FTIR, Raman, XPS, EDX, zeta potential, XRD, SEM/FESEM, TEM, AFM, surface area and porosimetry, VSM, DLS, thermoanalytical analysis (TG, DTA, DSC and DTG), among several others. These techniques enable the identification, location and quantification of chemical constituents, like elements, functional groups and molecules, as well as the study of the structure, topography, morphology, magnetic properties, and size, among other physical properties of materials. This information can provide great support for the assessment of the synthesis/functionalization of adsorbent materials as well as in the study of the adsorption process by the interactions between adsorbent and adsorbate. In the face of that, this review intends to be a comprehensive and concise guide for researchers that study adsorbent materials to consult the available characterization techniques and choose the most suitable ones for their specific needs.
... While peaks at 1630 and 1265 cm −1 correspond to -C=O stretching and C-O stretching respectively. FTIRs analysis confirmed that the surface of the colloidal AuNPs was covered with citrate groups, which are important for the stability of the prepared nanoparticles [23]. The binding interaction of Dox@AuNPs was further investigated using FT-IR studies. ...
Multi-drug resistance (MDR) in addition to the damage to non-malignant normal cells are the most difficult in cancer treatment. Drug delivery and Plasmonic photothermal therapy based on the use of resonant metallic nanoparticles have developed as promising techniques to destroy cancer cells selectively. In the present work, gold nanoparticles (AuNPs) were synthesized using trisodium citrate. The prepared AuNPs have a small size of 14 ± 4 nm and exhibit high stability with Zeta potential − 18 mV, AuNPs showed higher photothermal heating efficiency compared to irradiation with a 532 nm laser alone on the breast cancer cell line (MCF-7). Treatment of MCF-7 cells with 0.125 mM AuNPs coupled with laser irradiation for 6 min was found to significantly reduce (34%) the cell viability compared to 5% obtained with AuNPs in the same concentration and 26% with laser irradiation for 6 min without AuNPs. Moreover, the prepared AuNPs were used as an anticancer drug carrier for Doxorubicin (Dox), upon loading Dox to AuNPs there was a slight increase in the particle size to 16 ± 2 nm, FT-IR spectroscopic results showing the binding of Dox to AuNPs was through the –NH group. The potential cytotoxicity of the DOX@AuNPs nanocomposite was significantly increased compared to free DOX on the MCF7 cell line with a decrease in IC 50 . All these results suggested the potential use of AuNPs as therapeutic photothermal agents and drug carriers in cancer therapy.
... In the past decades, numerous research works [120][121][122] discussed the potential of nanoparticles (NPs) and their incorporation into biosensor systems in order to achieve the use of NPs in biosensor applications for the detection of food pathogens. Nanotechnologybased detection methods use metallic NPs, such as gold and silver [123], with tunable size and shape. ...
Nowadays, special importance is given to quality control and food safety. Food quality currently creates significant problems for the industry and implicitly for consumers and society. The effects materialize in economic losses, alterations of the quality and organoleptic properties of the commercial products, and, last but not least, they constitute risk factors for the consumer’s health. In this context, the development of analytical systems for the rapid determination of the sanitary quality of food products by detecting possible pathogenic microorganisms (such as Escherichia coli or Salmonella due to the important digestive disorders that they can cause in many consumers) is of major importance. Using efficient and environmentally friendly detection systems for identification of various pathogens that modify food matrices and turn them into food waste faster will also improve agri-food quality throughout the food chain. This paper reviews the use of metal nanoparticles used to obtain bio nanosensors for the purpose mentioned above. Metallic nanoparticles (Au, Ag, etc.) and their oxides can be synthesized by several methods, such as chemical, physical, physico-chemical, and biological, each bringing advantages and disadvantages in their use for developing nanosensors. In the “green chemistry” approach, a particular importance is given to the metal nanoparticles obtained by phytosynthesis. This method can lead to the development of good quality nanoparticles, at the same time being able to use secondary metabolites from vegetal wastes, as such providing a circular economy character. Considering these aspects, the use of phytosynthesized nanoparticles in other biosensing applications is also presented as a glimpse of their potential, which should be further explored.
... For example, the extinction coefficient of metal NPs is superior to that of organic dyes, which makes them attractive for the high sensitive metal-based colorimetric biosensors. [59,60] Due to the unique features of metal NPs, some colorimetric nano aptasensors have used probes labeled with Au and Fe NPs to detect TB sensitively. [61,62] Zhu et al. reported a sensitive and innovative colorimetric sensing strategy to detect TB based on TBA and magnetic NPs (MNPs). ...
Thrombin (TB) is classified among human blood coagulation proteins with key functions in hemostasis of blood vessels, wound healing, atherosclerosis, tissue adhesion, etc. Moreover, TB is involved as the main enzyme in the conversion of the fibrinogen to fibrin. Given the importance of TB detection in the clinical area, the development of innovative methods can considerably improve TB detection. Newly, aptasensors or aptamer-based biosensors have received special attention for sensitive and facile TB detection. In addition, the aptamer/nanomaterial conjugates have presented new prospects in accurate TB detection as nanoaptasensors. DNA-based enzymes or DNAzymes, as new biocatalysts, have many advantages over protein enzymes and can be used in analytical tools. This article reviews a brief overview of significant progresses regarding the various types of DNAzymes-based aptasensors and nano aptasensors developed for thrombin detection. In the following, challenges and prospects of TB detection by DNAzymes-based aptasensors are discussed.
... AuNPs are often preferred for the development of wearable viral-detection devices. In the literature, AuNPs have been widely employed in various types of viral detection, such as via (a) optical detection, which includes fluorescence enhancing and quenching [16,54], colorimetric [55][56][57], light scattering [58]; and via (b) electric-or catalytic-based detection with enzymatic redox electrochemical tags [59,60]. Table 2 summarizes the recent applications of AuNPs in the fabrication of sensors for viral detection. ...
Pandemics such as COVID-19 have highlighted the importance of point-of-care sensors for testing, tracing and treatment to minimise and manage infection. Biosensors have been widely deployed in portable devices such as glucose sensors and pregnancy tests. Their development for point-of-exposure virus detection or point-of-care devices is anticipated but their reliability for the accurate detection of viruses is critical. Nanomaterials, such as metal nanoparticles, magnetic nanoparticles, quantum dots, carbon-based nanomaterials, and molecularly imprinted polymer (MIP) nanoparticles, have been utilised in biosensors to enhance sensitivity. Molecularly imprinting is a cost-effective method to synthesise polymer for selective binding with an excellent property as biosensors. More research on MIP nanoparticles can be expected in the near future. The utilisation of nanomaterials in several types of transducers for biosensor devices is also illustrated to give an overview of their use. Finally, a summary is given together with a future perspective on how biosensors can be further developed as reliable, portable viral biosensors.
