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Topic Review
Photodynamic Therapy for Deep-Seated Tumors
Photodynamic therapy (PDT) works through the photoactivation of a specific photosensitizer (PS) in a tumor in the presence of oxygen. PDT is widely applied in oncology to treat various cancers as it has a minimally invasive procedure and high selectivity, does not interfere with other treatments, and can be repeated as needed. A large amount of reactive oxygen species (ROS) and singlet oxygen is generated in a cancer cell during PDT, which destroys the tumor effectively. However, the efficacy of PDT in treating a deep-seated tumor is limited due to three main reasons: Limited light penetration depth, the low oxygen concentration in the hypoxic core, and poor PS accumulation inside a tumor. Thus, PDT treatments are only approved for superficial and thin tumors. With the advancement of nanotechnology, PDT to treat deep-seated or thick tumors is becoming a reachable goal. In this review, we provide an update on the strategies for improving PDT with nanomedicine using different sophisticated-design nanoparticles, including two-photon excitation, X-ray activation, targeting tumor cells with surface modification, alteration of tumor cell metabolism pathways, the release of therapeutic gases, improvement of tumor hypoxia, and stimulation of host immunity.
  • 1.8K
  • 11 Oct 2021
Topic Review
Photocatalytic Degradation of Antibiotics
Various methods, including carbon filtration, ozonation, catalytic membranes, Fenton-like catalysis, sorption, and biodegradation have been employed to eliminate such enduring antibiotic substances. As a result, wastewater accumulates effluents from corporations, clinics, and farmland. Sewage treatment is typically regarded as the preferred method for treating these antibiotics. Photocatalysis has gained a lot of interest as an effective method for eliminating antibiotic contaminants since it is inexpensive, effective, and environmentally benign as it eliminates antibiotics in sunlight and under ambient conditions. The reactions endured by a semiconductor and the potential to absorb photons with energies higher than its energy band gap is called “photocatalytic degradation”.
  • 1.8K
  • 02 Mar 2023
Topic Review
CNT-Based Chemical Sensors
Carbon nanotubes (CNTs) combine high electrical conductivity with high surface area and chemical stability, which makes them very promising for chemical sensing. 
  • 1.8K
  • 10 Feb 2022
Topic Review
Spins in Semiconductor Nanoparticles
- Spin-dependent phenomena in semiconductors are analyzed starting from a theory of the dynamic nuclear polarization via numerous insightful findings in the realm of characterization and control through the nuclear spin polarization in nanoparticles and their aggregates into microparticles as potential contrast agents for magnetic resonance imaging (MRI) applications.  - Electron spin-dependent process of the photosensitized generation of singlet oxygen in porous silicon (Si) for photodynamic therapy application and design of Si-based nanoparticles with electron spin centers for MRI contrasting for cancer theranostics are discussed.  
  • 1.8K
  • 12 Jan 2021
Topic Review
Carbon Nanotube Sheet-Synthesis and Applications
 This paper gives an overview of different approaches to synthesize CNTs and then focuses on the floating catalyst method to form CNT sheets. A method is also described in this paper to modify the properties of macroscale carbon nanotube sheets produced by the floating catalyst method. This paper also discusses manufacturing obstacles and the possible commercial applications of the CNT sheet and CNTH sheet. Applications for CNT sheet include air and water filtering, energy storage applications, and compositing CNTH sheets to produce apparel with anti-microbial properties to protect the population from infectious diseases. The paper also provides an outlook towards large scale commercialization of CNT material.
  • 1.8K
  • 11 Nov 2020
Topic Review
Hot Electrons in Plasmon-Sensitized TiO2
Hot carriers are electron-hole pairs formed by Landau damping or chemical interface damping of particle plasmons. The term “hot electrons” not only describes the individual electrons themselves, but also describes the Fermi–Dirac distribution of electrons in a solid albeit with an elevated effective temperature—the effective temperatures involved when considering the carrier kinetic energies and carrier densities in the solid, and not that of the solid itself- as opposed to thermal equilibrium. Typically, hot carriers lose their excess energy and relax to thermal equilibrium within a few picoseconds of formation due to a variety of scattering processes. Therefore, it is very difficult to extract useful work from hot carriers with thermodynamic efficiencies that are of interest for practical devices. However, heterojunctions of TiO2 with coinage metals have been consistently shown to be effective in utilizing hot carriers to perform useful work, such as driving a chemical reaction or generating an electric current. A secondary benefit of such TiO2-coinage metal heterojunctions is the "visible light sensitization" effect which allows broader harvesting of visible light. 
  • 1.8K
  • 24 May 2021
Topic Review
Application of MXenes Material for Sensors
MXenes are a class of 2D early transition nitride, metal carbides, and carbonitrides that are created by the group that selectively etches IIIA/IVA elements from three-dimensional (3D) MAX -phases. MXenes, a rising star of 2D materials, are unique in that they combine the hydrophilicity of their terminating surfaces with the metallic conductivity of transition metal carbonitrides or carbides. Because of its unusual accordion-like structure and the functional groups that are added to the surface during their synthesis, MXenes have enticing electrical, optical, and magnetic properties that can be used for sensing, energy storage, and electromagnetic shielding.
  • 1.8K
  • 15 Feb 2023
Topic Review
Heavy Metal Adsorption Using Magnetic Nanoparticles
Research on contamination of groundwater and drinking water is of major importance. Due to the rapid and significant progress in the last decade in nanotechnology and its potential applications to water purification, such as adsorption of heavy metal ion from contaminated water, a wide number of articles have been published. An evaluating frame of the main findings of recent research on heavy metal removal using magnetic nanoparticles, with emphasis on water quality and method applicability, is presented. A large number of articles have been studied with a focus on the synthesis and characterization procedures for bare and modified magnetic nanoparticles as well as on their adsorption capacity and the corresponding desorption process of the methods are presented.
  • 1.8K
  • 21 Dec 2021
Topic Review
TiO2-Based Nanostructures for Microbial Inactivation
Pathogenic microorganisms can spread throughout the world population, as the current COVID-19 pandemic has dramatically demonstrated. In this scenario, a protection against pathogens and other microorganisms can come from the use of photoactive materials as antimicrobial agents able to hinder, or at least limit, their spreading by means of photocatalytically assisted processes activated by light—possibly sunlight—promoting the formation of reactive oxygen species (ROS) that can kill microorganisms in different matrices such as water or different surfaces without affecting human health. Here, we focus the attention on TiO2 nanoparticle-based antimicrobial materials, intending to provide an overview of the most promising synthetic techniques, toward possible large-scale production, critically review the capability of such materials to promote pathogen (i.e., bacteria, virus, and fungi) inactivation, and, finally, take a look at selected technological applications.
  • 1.8K
  • 08 Dec 2020
Topic Review
Highly Dispersed Metal Catalysts
Single-atom catalysts (SACs), consisting of metals atomically dispersed on a support, are considered as advanced materials bridging homogeneous and heterogeneous catalysis, representing the catalysis at the limit. The enhanced performance of these catalysts is due to the combination of distinct factors such as well-defined active sites, comprising metal single atoms in different coordination environments also varying its valence state and strongly interacting with the support, in this case porous carbons, maximizing then the metal efficiency in comparison with other metal surfaces consisting of metal clusters and/or metal nanoparticles.
  • 1.8K
  • 06 Apr 2021
Topic Review
Microwave-Assisted Preparation of Luminescent Materials
Luminescent inorganic materials are used in several technological applications such as light-emitting displays, white LEDs for illumination, bioimaging, and photodynamic therapy. Usually, inorganic phosphors (e.g., complex oxides, silicates) need high temperatures and, in some cases, specific atmospheres to be formed or to obtain a homogeneous composition. Low ionic diffusion and high melting points of the precursors lead to long processing times in these solid-state syntheses with a cost in energy consumption when conventional heating methods are applied. Microwave-assisted synthesis relies on selective, volumetric heating attributed to the electromagnetic radiation interaction with the matter. The microwave heating allows for rapid heating rates and small temperature gradients yielding homogeneous, well-formed materials swiftly. Luminescent inorganic materials can benefit significantly from microwave-assisted synthesis for high homogeneity, diverse morphology, and rapid screening of different compositions. The rapid screening allows for fast material investigation, whereas the benefits of enhanced homogeneity include improvement in the optical properties such as quantum yields and storage capacity.
  • 1.8K
  • 23 Jun 2021
Topic Review
Intranasal Liposomes for Vaccine Delivery
Liposomes are safe, biocompatible, and biodegradable spherical nanosized vesicles produced from cholesterol and phospholipids. Liposomes have been widely administered intranasally for systemic and brain delivery. Intranasal liposomes are also a potential approach for vaccine delivery. Liposomes can be used as a platform to load antigens and as vaccine adjuvants to induce a robust immune response. 
  • 1.8K
  • 29 Jan 2023
Topic Review
M13 Bacteriophage-Based Biosensors
New virus-based sensor systems that operate on M13 bacteriophage infrastructure have attracted considerable attention. These systems can detect a range of chemicals with excellent sensitivity and selectivity. Filaments consistent with M13 bacteriophages can be ordered by highly established forms of self-assembly. This allows M13 bacteriophages to build a homogeneous distribution and infiltrate the network structure of nanostructures under mild conditions.
  • 1.8K
  • 07 Jun 2021
Topic Review
Application Fields of Silver Nanoparticles
New antiviral drugs and new preventive antiviral strategies are a target of intense scientific interest. Thanks to their peculiar properties, nanomaterials play an important role in this field, and, in particular, among metallic materials, silver nanoparticles were demonstrated to be effective against a wide range of viruses, in addition to having a strong antibacterial effect. Although the mechanism of antiviral action is not completely clarified, silver nanoparticles can directly act on viruses, and on their first steps of interaction with the host cell, depending on several factors, such as size, shape, functionalization and concentration. 
  • 1.8K
  • 24 Mar 2023
Topic Review
SAM-Based Electrodes
Self-assembled molecular monolayers (SAMs) are long recognized as crucial "bridges" between redox enzymes and solid electrode surfaces, on which the enzymes undergo direct electron transfer (DET)—for example, in enzymatic biofuel cells (EBFCs) and biosensors. SAMs possess a wide range of terminal groups that enable productive enzyme adsorption and fine-tuning in favorable orientations on the electrode. The tunneling distance, the SAM chain length, and the contacting terminal SAM groups are the most significant factors in SAM-controlled DET-type bioelectrocatalysis.
  • 1.7K
  • 08 Feb 2021
Topic Review
Nanopore Technology in Gene Sequencing
Nanopore technology refers to nano-scale holes embedded in a thin membrane structure to detect the potential change when charged biological molecules smaller than nanopore pass through the hole. Therefore, nanopore technology has the potential to sense and analyze single-molecule amino acid, DNA, RNA, etc.. In this review, we will focus on the applications of nanopore technology in gene sequencing.
  • 1.7K
  • 02 Aug 2021
Topic Review
Nanomaterials Application in Endodontics
The medical procedures in endodontics are time-consuming and mostly require several visits to be able to achieve the proper result. In this field of dentistry, there are still major issues about the removal of the mostly bacterial infection from the dental root canals. It has been confirmed that nanoparticles are much more efficient than traditional materials and appear to have superior properties when it comes to surface chemistry and bonding. Their unique antibacterial properties are also promising features in every medical procedure, especially in endodontics. High versatility of use of nanomaterials makes them a powerful tool in dental clinics, in a plethora of endodontic procedures, including pulp regeneration, drug delivery, root repair, disinfection, obturation and canal filling. 
  • 1.7K
  • 22 Nov 2021
Topic Review
Quantum Dots for Optoelectronic Applications
Quantum dots (QDs) are tiny semiconductor particles that typically range in size from 2 to 10 nanometers. Because of their small size, they have unique optical and electrical properties, resulting in quantum confinement of electrons and holes within the material. This confinement results in discrete energy levels, and the energy of the confined particles is determined by the size of the QDs QDs could be used in a variety of applications, including displays, solar cells, medical imaging, and quantum computing.. They are typically only a few nanometers in size. QDs can be employed as a light-sensitive substance, also referred to as a photoconductive substance, in a photodetector.
  • 1.7K
  • 06 Apr 2023
Topic Review
Metal Ion Detection by Glutathione
Low cost, sensitive, selective, and rapid methods for heavy metal ion (HMI) detection are of growing demand, and HMI biosensors have great potential in meeting this need due to their timeliness, cost-effectiveness and convenience in operation. The most widely reported peptide probe for HMI detection is glutathione (GSH), especially in case of lead ion (Pb2+) detection. GSH is highly stable, cost-effective, and easy to immobilize on a sensor. 
  • 1.7K
  • 10 Jun 2021
Topic Review
Graphene-Based Strategies for Viral Diseases
The occurrence of new pandemic  viruses, such as SARS-CoV-1 (2003), MERS-CoV (2012) and SARS-CoV-2 (2019) has  indicated an urgent need for diagnostic tools able to reliably identify infected individuals and to determine if the infection is in the acute phase. Although nanotechnology based on graphene has been poorly applied for the rapid diagnosis of viral diseases, the extraordinary properties of graphene have been recently exploited for the diagnosis of COVID-19. Novel graphene-based field-effect transistor (GFET) biosensors were developed for the quantitative detection of viral RNA and viral spike protein. The fabrication of COVID-19 FET sensor for spike protein recognition is based on the integration of the SARS-CoV-2 spike antibody with graphene, whereas the GFET sensor for viral RNA recognition exploited the CRISPR/Cas biotechnology.
  • 1.7K
  • 27 Oct 2020
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