جستجوی مقالات مرتبط با کلیدواژه « نانوساختارها » در نشریات گروه « پزشکی »

Organic-inorganic hybrid nanoflowers with flower-like morphology are new nanostructures comprising organic and inorganic components. In general, the organic component of hybrid nanoflowers mostly consists of proteins, DNA, RNA, plant extracts, metabolites, and natural polymers; and the inorganic component composes of various metal phosphates, including copper, calcium, manganese, iron, zinc, cobalt, cadmium, aluminum, silver, gold, etc. Until now, five notable procedures have been introduced for their synthesis, including biomineralization, ultra-fast sonication, the two-step method, shear stress, and the concentrated method. These nanostructures have many promising applications in diverse fields, such as the immobilization of enzymes and biomolecules, bio-catalysis of chemical reactions, bioremediation, electrochemical biosensors, drug and gene carriers, diagnosis of various diseases, photothermal therapy, etc., and wide range of research has been performed on them in the last recentdecade.Google Scholar, Scopus, ScienceDirect, and Springer databases were searched using the keywords hybrid nanostructure, nanoflower, biosciences, and biocatalyst to find related articles.Studying these organic-inorganic hybrid nanocrystals may lead to finding new creative solutions in the effective application of enzyme-based systems, the rapid development of bionanomaterials, and biotechnology industries. The present review has investigated the different types of hybrid nanoflowers, their synthesis procedures and structural characteristics, and their applications in biosciences.

The recording of electrophysiological activities of brain neurons in the last half-century has been considered as one of the effective tools for the development of neuroscience. One of the techniques for recording the activity of nerve cells is the multi-electrode arrays (MEAs). Microelectrode arrays (MEAs) are usually employed to record electrical signals from electrogenic cells like neurons or cardiomyocytes. MEAs consist of an array of planar or three-dimensional electrodes that act as electrical interfaces and record cellular signals or stimulate cells. These platforms can be used in different applications including neuroscience studies, prostheses and rehabilitation, deep brain stimulation (DBS), cardiac pacemakers, retinal and cochlear implants, or for brain-computer interfaces (BCI) in general. Multi-electrode arrays are known as long-term recording and non-invasive devices. The MEA structure includes arrays of electrodes with micrometer and nanometer dimensions which are designed to stimulate and record the electrical activity of cells, and are fabricated using micromachining technologies. MEAs should be biocompatible to serve as a substrate for cell growth. On the other hand, they must have low impedance to be able to provide a high signal-to-noise ratio, and small size to offer a suitable spatial resolution for recording. MEAs are usually fabricated on glass substrates patterned with high-conductivity metals such as gold, iridium or platinum, which are insulated with a biocompatible layer. Despite fast progress, current multi-electrode arrays for neural applications still face limitations such as low signal-to-noise ratio and spatial resolution. To achieve better spatial resolution and lower noise levels and therefore more accurate signal, it is necessary to develop arrays with smaller sizes and lower impedance. Meanwhile, many nanostructures such as graphene, carbon nanotubes, gold nanoparticles, and also conductive polymers have become attractive candidates for this application due to their interesting properties. In this paper, the technology of multi-electrode arrays, how it works and its various parts are introduced, and finally, the challenges and developments in this field are investigated. Multi-electrode array technology is used for neuroscience research, neural network analysis, drug effects screening, and neural prosthesis studies.

Most infectious bacteria can at least be resistant to some antibiotics. Moreover, Drug resistant bacteria are known as multi-resistance organisms. Nowadays, the urgently need for new strategies is increasingly felt to control bacterial activity and in this regard, a very promising approach can be nanomaterials. Today's knowledge of nanoscale synthesis has to be considered as a global strategy. Nanotechnology includes the engineering and manufacturing of materials at the atomic and molecular scale and it refers to structures of about 1-100 nm in at least one dimension. In addition to nanotechnology applications, we can mention the new science of nanomedicine, which we are currently seeing its enormous effects in the pharmaceutical and medical biotechnology industries. This science is rapidly becoming a major driving force in the field of antimicrobial activity in the world. This paper focuses on the use of nanotechnology as a new tool for tackling the current challenges in the field of infectious disease treatment. Therefore, for safer use of this new technology, clinical trials and further research are needed at the molecular biology level. Ultimately, the adverse effects of nanomaterials cannot be ruled out.