Nano-Biotechnology
Mehran Alavi; Michael R. Hamblin; Ermia Aghaie; Seyed Ali Reza Mousavi; Mohammad Hajimolaali
Abstract
Up to one million secondary metabolites are found in plant species, some of which may have desirable therapeutic activities. Among these secondary metabolites, catechin, gallic acid, and epigallocatechin-3-gallate are natural phenolic compounds with promising antioxidant and antibacterial activity. However, ...
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Up to one million secondary metabolites are found in plant species, some of which may have desirable therapeutic activities. Among these secondary metabolites, catechin, gallic acid, and epigallocatechin-3-gallate are natural phenolic compounds with promising antioxidant and antibacterial activity. However, these compounds have disadvantages of poor solubility, low bioavailability in physiological conditions, and side effects in patients. Therefore new strategies could rely on formulations with other synthetic and natural materials. Nanoformulations of secondary metabolites could be new efficient strategies to treat many chronic bacterial infections. Combinations and conjugates of catechin, gallic acid, and epigallocatechin-3-gallate with various antibiotics could reduce the dose of these compounds, increase their antibacterial activity, and decrease cytotoxicity against healthy cells. For instance, a smart combination of two or more secondary metabolites may improve therapeutic applications in physiological conditions. In this regard, the growth of antibiotic-resistant bacteria, specifically multidrug-resistant bacteria with overexpression of efflux pumps and expression of the penicillinase enzyme, has been inhibited significantly. According to recent investigations, this review will discuss the advances and challenges of new micro and nanoformulations of these natural products.
Nano-Biotechnology
Mehran Alavi; Michael R. Hamblin
Abstract
Various microorganisms are located on the human skin, mucous membrane and inside the human body. Many of these microorganisms are beneficial and few are even essential, however, some pathogens are known to cause infection and have the ability to attack and damage the host tissue. Treatment of infectious ...
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Various microorganisms are located on the human skin, mucous membrane and inside the human body. Many of these microorganisms are beneficial and few are even essential, however, some pathogens are known to cause infection and have the ability to attack and damage the host tissue. Treatment of infectious bacterial disease by antibiotics is one of the major conventional strategies. Gram-positive and Gram-negative bacteria have developed resistance to conventional antibiotics by various mechanisms, including overexpression of efflux pumps, preventing drug penetration into the cells, genetic mutations, increased production of competitive inhibitors of antibiotics, or overexpression of enzymes that inactivate or hydrolyze antibiotics. Consequently, finding a new approach to overcome these hindrances is vital for the treatment of severe bacterial infections. Nanomaterials can be effective therapeutic compounds, with unique properties compared to bulk materials. Metal and metal oxide nanoparticles, particularly silver nanoparticles, have demonstrated strong antibacterial activity against most (if not all) multidrug-resistant bacteria. Several antibacterial mechanisms have been proposed for these nanoparticles, however, their interaction with bacterial nucleic acids is not completely understood, so this review discusses recent advances in this area.
Nano-Biotechnology
Mehran Alavi; Michael R. Hamblin; M. R. Mozafari; Irwin Rose Alencar de Menezes; Henrique Douglas Melo Coutinho
Abstract
Bacterial infections can be caused by contamination of labile blood products with specific bacteria, such as Staphylococcus aureus and Staphylococcus epidermidis. Hospital equipment, bio-protective equipment, delivery systems, and medical devices can be easily contaminated by microorganisms. Multidrug-resistant ...
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Bacterial infections can be caused by contamination of labile blood products with specific bacteria, such as Staphylococcus aureus and Staphylococcus epidermidis. Hospital equipment, bio-protective equipment, delivery systems, and medical devices can be easily contaminated by microorganisms. Multidrug-resistant bacteria can survive on various organic or inorganic polymeric materials for more than 90 days. Inhibiting the growth and eradicating these microorganisms is vital in blood transfusion processes. Blood bags and other related medical devices can be improved by the incorporation of organic or inorganic nanomaterials, particularly silicon dioxide (SiO2) nanoparticles. The addition of solid organic or inorganic nanoparticles to synthetic polymers or biopolymers can provide new properties in addition to antimicrobial activity. Among these NPs, formulations composed of SiO2 nanoparticles and polymers have been shown to improve the mechanical and antimicrobial properties of catheters, prosthetic inserts, blood bags, and other medical devices SiO2 nanoparticles possess several advantages, including large-scale synthetic availability, simple one-pot synthesis methods, porous structure for loading antibacterial agents, good biocompatibility, and thermal stability. Plasticized polyvinyl chloride is the main polymer, which has been functionalized by these nanoparticles. In this review, we discuss the recent advances and challenges regarding the functionalization of polyvinyl chloride by SiO2 nanoparticles to hinder bacterial contaminations in blood products.
Nano-Biotechnology
Mehran Alavi; Mahendra Rai; Fleming Martinez; Danial Kahrizi; Haroon Khan; Irwin Rose Alencar de Menezes; Henrique Douglas Melo Coutinho; José Galberto Martins Costa
Abstract
The applications of nanoparticles in various practical fields, owing to their unique properties compared with bulk materials, have been occupying the minds of scientists for several decades. In this regard, a combination of pharmacology and nanotechnology has contributed to producing newer effective ...
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The applications of nanoparticles in various practical fields, owing to their unique properties compared with bulk materials, have been occupying the minds of scientists for several decades. In this regard, a combination of pharmacology and nanotechnology has contributed to producing newer effective anticancer and antimicrobial agents to inactivate resistant cancer cells and microorganisms, specifically multidrug-resistant ones. The physicochemical properties of nanoparticles based on metalloid, metal, and metal oxides such as selenium, silver, gold, titanium dioxide, zinc oxide, copper oxide, platinum, and magnesium oxide, have been well known and referred to as anticancer and antimicrobial agents or carriers. The inactivation and eradication of Gram-positive and Gram-negative bacteria may be mainly resulted from the oxidative damages in the bacterial medium. Overall, metalloid, metal and metal oxide NPs can be functionalized by other antibacterial or anticancer agents and biocompatible stabilizers to increase their efficiency in physiological conditions. However, the undesirable cytotoxicity of these nanoparticles in physiological conditions is the major hindrance to their application in the pharmaceutical industry and therapeutics. Nevertheless, it is expected that these problems will be solved in the near future. Therefore, the main objective of this review is to report an overview of the recent signs of progress in increasing anticancer and antibacterial mechanisms of metal and metal-based nanoparticles.
Nano-Biotechnology
Mehran Alavi; Mahendra Rai
Abstract
Finding efficient therapeutic strategies to fight antibiotic-resistant bacteria is a complicated affair specifically in the therapy of chronic bacterial infections related to hospital-acquired infections. Recently, three major antibacterial systems based on antisense RNA, CRISPR-Cas9, and metal/metal ...
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Finding efficient therapeutic strategies to fight antibiotic-resistant bacteria is a complicated affair specifically in the therapy of chronic bacterial infections related to hospital-acquired infections. Recently, three major antibacterial systems based on antisense RNA, CRISPR-Cas9, and metal/metal oxide nanoparticles particularly silver (Ag) nanoparticles have shown more effective antibacterial activity compared to conventional antibiotics. ROS generation, attachment to the cell membrane, disruption of bacterial envelop, inactivation of electron transport chain, decreasing the local pH, modulation of cell signaling, and denaturation of biological macromolecules such as proteins and nucleic acids have been found as the main antibacterial functions of Ag nanoparticles. Antisense RNA, a single-stranded RNA, can hybridize with complementary genes in messenger RNA (mRNA) followed by blockage translation of these genes into proteins. Moreover, CRISPR (clustered regularly interspaced short palindromic repeats) is a family of viral DNA sequences derived from bacteriophages, which can target and destroy foreign DNA by nuclease activity. There are 2 classes and 6 subtypes (I-VI) of CRISPR-Cas systems, which may be engineered as potential antibacterial agents to target specific sequences. Therefore, here, recent advances and challenges for the antibacterial application of these three therapeutic agents are presented.
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