{"id":227,"date":"2021-01-06T01:32:10","date_gmt":"2021-01-06T06:32:10","guid":{"rendered":"https:\/\/www.cd-bioparticles.com\/blog\/?p=227"},"modified":"2021-01-06T01:32:10","modified_gmt":"2021-01-06T06:32:10","slug":"how-do-silver-nanoparticles-kill-bacteria","status":"publish","type":"post","link":"https:\/\/www.cd-bioparticles.com\/blog\/nanoparticles\/how-do-silver-nanoparticles-kill-bacteria\/","title":{"rendered":"How Do Silver Nanoparticles Kill Bacteria?"},"content":{"rendered":"\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"\/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-1-1024x683.jpg\" alt=\"\" class=\"wp-image-228\" srcset=\"\/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-1-1024x683.jpg 1024w, \/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-1-300x200.jpg 300w, \/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-1-768x512.jpg 768w, \/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-1-120x80.jpg 120w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><\/div>\n\n\n\n<p><a href=\"https:\/\/www.cd-bioparticles.com\/product\/silver-nanoparticles-list-166.html\">Silver\nnanoparticles<\/a> (AgNPs) are particles composed of silver atoms, and their\nparticle sizes are usually in the range of 100 nm. Due to their unique physical\nand chemical properties, silver nanoparticles have been widely used in medical,\nfood, health, consumer, and industrial fields. These properties include\noptical, electrical, and thermal, high electrical conductivity, and biological\nproperties. Recently, silver nanoparticles have been frequently used in many\ntextiles, keyboards, wound dressings, and biomedical equipment.<\/p>\n\n\n\n<p>As\na hot spot in the research of antibacterial materials, silver nanoparticles\nhave the advantages of high efficiency and broad-spectrum, not easy to produce\ndrug resistance and high safety. However, there are still different views on\nthe understanding of nano-silver antimicrobial agents, and further research is\nstill going on.<\/p>\n\n\n\n<p>There\nare many examples of using silver as an antibacterial material in daily life.\nFor example, when the skin is injured, the medical staff will use gauze made of\nsilver wire to cover the skin wound; storing food in silver containers can\nprolong the shelf life of the food, and so on. After the discovery of\nantibiotics in the 1930s, silver antibacterial materials were ignored due to\nthe widespread use of antibiotics. In recent years, the problem of drug\nresistance of bacteria caused by the abuse of antibiotics is serious, so the\nnew antibacterial materials with low cost and high safety represented by silver\nnanoparticles have attracted people&#8217;s attention.<\/p>\n\n\n\n<p>The\nadvantages of silver nanoparticles used in antibacterial material<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>A high degree of safety.\nCompared with silver ions, silver nanoparticles show strong antibacterial\nactivity to microorganisms at very low concentrations (at nanomoles or\nmicromoles grade), while they are less toxic to mammals and rarely have\ncomplications.<\/li><li>Long-lasting antibacterial\nproperties. Silver nanoparticles can be loaded on chitosan and other carriers\nto continuously release silver ions, maintaining a relatively stable silver\nconcentration, and achieving the purpose of lasting antibacterial.<\/li><li>Broad-spectrum antibacterial\nactivity. Silver nanoparticles can effectively inhibit more than 650 kinds of\npathogenic bacteria, including <em>Pseudomonas aeruginosa<\/em>, <em>Staphylococcus\naureus<\/em>, <em>Escherichia coli<\/em>, dermatophytes, other fungi, and even\nHIV-1.<\/li><li>Not easy to develop drug\nresistance. Bacteria treated with silver nanoparticles basically cannot\nsurvive, which can prevent bacteria from developing drug resistance.<\/li><li>Little side effects and easy to\nuse.<\/li><\/ul>\n\n\n\n<p>How\ndo silver nanoparticles kill bacteria?<\/p>\n\n\n\n<p>At\npresent, the antibacterial mechanism of silver nanoparticles is not enough. It\nis generally believed that silver nanoparticles release silver ions and induce\nthe production of reactive oxygen species (ROS). Other studies have found that\nsilver nanoparticles themselves directly play an antibacterial role and\ncooperate with the release of silver ions to play a role. The antibacterial\nprinciples of silver nanoparticles generally recognized at this stage mainly\ninclude affecting the environment in which bacteria live, destroying cell membrane,\ninhibiting DNA replication, etc. <\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>By affecting the living\nenvironment of bacteria<\/li><\/ul>\n\n\n\n<p>In\nsolution, silver nanoparticles release silver ions or are oxidized by oxygen to\nform the nano-silver oxide and then release silver ions due to the synergistic\naction of oxygen and protons. Some studies have suggested that silver\nnanoparticles themselves have no effect on bacteria, and the inhibitory effect\ncomes from the release of silver ions and is strictly dependent on the\nconcentration of oxygen. In addition, silver ions can combine with nutrient\nelements in the system to reduce the concentration of elements necessary for\nbacterial growth. Some studies have also shown that silver nanoparticles induce\noxygen to produce oxygen ions and water molecules to produce hydroxyl groups,\nwhich aggravate the consumption of oxygen and attack the cell membrane at the\nsame time. At a higher concentration of silver ions, silver ions can be\nre-aggregated into zero-valent silver ions, so this process continues to\nconsume oxygen and play a bacteriostatic effect.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>By destroying the cell membrane<\/li><\/ul>\n\n\n\n<p>Silver\nions and silver nanoparticles loaded with positive charges are adsorbed on the\ncell membrane by electrostatic attraction with negatively charged bacterial\nproteins. Because of its high surface energy and dispersion, the chemical\ninteraction between silver nanoparticles and the cell membrane destroys the\nintegrity of the cell membrane, which is especially obvious in the part where\nelectrons are enriched. It leads to the loss of normal function of the cell membrane,\nsuch as nutrient permeation. At the same time, silver nanoparticles and silver\nions act as peroxidation inducers of the membrane and interact with some\nproteins and phospholipids to induce membrane damage or decomposition.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>By inhibiting DNA replication<\/li><\/ul>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"628\" src=\"\/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-2-1024x628.jpg\" alt=\"\" class=\"wp-image-229\" srcset=\"\/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-2-1024x628.jpg 1024w, \/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-2-300x184.jpg 300w, \/blog\/wp-content\/uploads\/2021\/01\/Silver-Nanoparticles-Kill-Bacteria-2-768x471.jpg 768w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><\/div>\n\n\n\n<p>Silver\nnanoparticles can enter the cell through endocytosis and other mechanisms to\ncause further damage to the cell. DNA is the most important genetic information\nmaterial, any damage to DNA will cause cell mutation or death. The mechanism of\nDNA damage by silver nanoparticles may be that silver nanoparticles can\ninteract with parathion compounds in DNA. Silver nanoparticles may conjugate\nwith pathogenic bacteria DNA bases and form cross-links, replacing the hydrogen\nbonds between purine and pyrimidine adjacent nitrogen. This will cause DNA\nshrinkage, destroying DNA structure, and inhibiting its replication process,\nresulting in cell death.<\/p>\n\n\n\n<p>What\nare the risks of using silver nanoparticles?<\/p>\n\n\n\n<p>Silver\nnanoparticles also expose some problems when used as antibacterial materials,\nsuch as safety problems caused by silver accumulation and migration. When\nsilver is enriched to a higher concentration, it will do great harm to human\nbeings and mammals and will enter the mitochondria, embryos, liver, and\ncirculatory system with respiration. Some studies have pointed out that silver\nnanoparticles are more toxic than metal nanoparticles such as aluminum and\ngold, so the application range and dose of silver nanoparticles as\nantibacterial materials are also worthy of research and attention.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Silver nanoparticles (AgNPs) are particles composed of silver atoms, and their particle sizes are usually in the range of 100<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[61,12],"class_list":["post-227","post","type-post","status-publish","format-standard","hentry","category-nanoparticles","tag-bacteria","tag-silver-nanoparticles"],"_links":{"self":[{"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/posts\/227","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/comments?post=227"}],"version-history":[{"count":1,"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/posts\/227\/revisions"}],"predecessor-version":[{"id":230,"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/posts\/227\/revisions\/230"}],"wp:attachment":[{"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/media?parent=227"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/categories?post=227"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.cd-bioparticles.com\/blog\/wp-json\/wp\/v2\/tags?post=227"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}