{"id":1680,"date":"2020-12-16T03:35:44","date_gmt":"2020-12-16T08:35:44","guid":{"rendered":"http:\/\/www.bocsci.com\/blog\/?p=1680"},"modified":"2020-12-27T20:55:44","modified_gmt":"2020-12-28T01:55:44","slug":"magnetic-beads-mbs-for-drug-delivery","status":"publish","type":"post","link":"https:\/\/www.bocsci.com\/blog\/magnetic-beads-mbs-for-drug-delivery\/","title":{"rendered":"Magnetic Beads (MBs) for Drug Delivery"},"content":{"rendered":"<p>With the improvement of nanotechnology, many advanced&nbsp;research paths have been opened up in different fields, and one&nbsp;of the most promising applications is drug delivery&nbsp;systems (DDSs) for cancer treatment. In the past few decades, a variety of different types of nanoparticles encompassing various of routes of administration&nbsp;have been designed to achieve &#8220;precision treatment&#8221; of drugs, and the <a href=\"https:\/\/www.bocsci.com\/superparamagnetic-iron-oxide-nano.html\">magnetic beads<\/a>&nbsp;(MBs)-based carriers are&nbsp;one of them.<\/p>\n<p><strong><b>S<\/b><\/strong><strong><b>tructure<\/b><\/strong><strong><b>s<\/b><\/strong><strong><b>&nbsp;of Magnetic Carriers<\/b><\/strong><\/p>\n<p>The carriers based on functionalized MBs usually have two types of structures:<\/p>\n<ul>\n<li>Magnetic particle core (usually magnetite,Fe<sub>3<\/sub>O<sub>4<\/sub>, or maghemite, \u03b3 -Fe<sub>2<\/sub>O<sub>3<\/sub>) coated with biocompatible polymer.<\/li>\n<li>Porous biocompatible polymer in whichmagnetic nanoparticles are precipitated inside the pores.<\/li>\n<\/ul>\n<p>Recent developmental work on carriers has&nbsp;paid more attention to&nbsp;new polymeric or inorganic coatings on magnetite\/maghemite&nbsp;nanoparticles, while noble metal coatings such&nbsp;as gold are also being considered.<\/p>\n<p><strong><b>Drug Release Mechanism<\/b><\/strong><\/p>\n<p>In general, there are three main mechanisms for releasing drug molecules&nbsp;from the functionalized magnetic beads (MBs) into blood vessels&nbsp;or tissues.<\/p>\n<ul>\n<li><b><\/b><strong><b>Diffusion <\/b><\/strong><\/li>\n<\/ul>\n<p>When&nbsp;drug molecules dissolve around or within&nbsp;the beads&nbsp;and migrate out of&nbsp;the beads, they will diffuse in body fluids.<\/p>\n<ul>\n<li><b><\/b><strong><b>Degradation <\/b><\/strong><\/li>\n<\/ul>\n<p>When the polymer chains are hydrolyzed&nbsp;into lower&nbsp;molecular weight substances, degradation&nbsp;occurs,&nbsp;thereby effectively releasing the drug molecules&nbsp;trapped by the chains.<\/p>\n<ul>\n<li><b><\/b><strong><b>Swelling Followed by Diffusion<\/b><\/strong><\/li>\n<\/ul>\n<p>As for&nbsp;the swelling controlled&nbsp;release systems, they are initially dry. However, when&nbsp;they are placed in the body, they swell,&nbsp;enabling the drug&nbsp;molecules to diffuse from the swollen network.<\/p>\n<p><strong><b>How it works?<\/b><\/strong><\/p>\n<p>In magnetic drug delivery system, cytotoxic drugs&nbsp;are&nbsp;usually attached to biocompatible magnetic bead carriers. These drug-carrier complexes are usually injected into the patient via the circulatory system. When the complexes enteres&nbsp;the bloodstream, an&nbsp;external high-gradient magnetic field will be used to concentrate the complexes on&nbsp;a specific target site in the body, such as tumor cells&nbsp;or diseased tissues. Once the drug-carrier complexes aggregates&nbsp;at the&nbsp;target site, the loaded drugs can be released either via enzymatic activity or&nbsp;changes in physiological conditions such as pH, osmolality,&nbsp;or temperature, and then be taken up by tumor cells.&nbsp;This kind of magnetic targeted drug delivery approach indeed has major advantages over the normal,&nbsp;non-targeted&nbsp;chemotherapies.<\/p>\n<p><a href=\"http:\/\/www.bocsci.com\/blog\/wp-content\/uploads\/2020\/12\/Schematic-illustration-for-magnetic-drug-delivery-system-in-cross-section.png\"><img decoding=\"async\" loading=\"lazy\" class=\" wp-image-1681 aligncenter\" src=\"http:\/\/www.bocsci.com\/blog\/wp-content\/uploads\/2020\/12\/Schematic-illustration-for-magnetic-drug-delivery-system-in-cross-section-300x188.png\" alt=\"\" width=\"530\" height=\"332\" srcset=\"https:\/\/www.bocsci.com\/blog\/wp-content\/uploads\/2020\/12\/Schematic-illustration-for-magnetic-drug-delivery-system-in-cross-section-300x188.png 300w, https:\/\/www.bocsci.com\/blog\/wp-content\/uploads\/2020\/12\/Schematic-illustration-for-magnetic-drug-delivery-system-in-cross-section.png 605w\" sizes=\"(max-width: 530px) 100vw, 530px\" \/><\/a><\/p>\n<p style=\"text-align: center;\"><strong><b>F<\/b><\/strong><strong><b>ig. 1 <\/b><\/strong>Schematic illustration for magnetic drug delivery system in&nbsp;cross-section. (<em><i>Applied Physics<\/i><\/em>&nbsp;2003, 36 (13), R167-R181)<\/p>\n<p><strong><b>Merits &amp; <\/b><\/strong><strong><b>L<\/b><\/strong><strong><b>imitations <\/b><\/strong><\/p>\n<p>Drug delivery system employing magnetic beads as carriers is a promising cancer treatment because it&nbsp;can realize a precise targeted delivery pattern. On the one hand, it&nbsp;can reduce the amount of&nbsp;systemic distribution of the cytotoxic drugs, thus reducing&nbsp;the associated side-effects. On the other hand, it&nbsp;can reduce the required&nbsp;dosage&nbsp;through&nbsp;more efficient, locally targeted drugs.<\/p>\n<p>However, the magnetic drug delivery system based on <a href=\"https:\/\/www.bocsci.com\/superparamagnetic-iron-oxide-nano.html\">MBs<\/a>&nbsp;is very promising, even if there are still some limitations and problems that need to be overcome.<\/p>\n<ul>\n<li>The possibility ofembolization of the blood vessels in the target region due to&nbsp;accumulation of the magnetic carriers<\/li>\n<li>Difficulties in scalingup from animal models due to the large distance between the&nbsp;target site and the magnet<\/li>\n<li>Drugs are nolonger attracted by&nbsp;the magnetic field once they are released<\/li>\n<li>Toxic responsesto the magnetic carriers are not sure.<\/li>\n<\/ul>\n<p><strong><b>R<\/b><\/strong><strong><b>eference<\/b><\/strong><strong><b>s<\/b><\/strong><\/p>\n<p>1. Pankhurst, Q. A.; Connolly, J.; <em><i>et al<\/i><\/em>. Applications of magnetic nanoparticles in biomedicine. <em><i>Journal of Physics D: Applied Physics<\/i><\/em>2003, 36 (13), R167-R181.<\/p>\n<p>2. Hans, M. L.; Lowman, A., Biodegradable Nanoparticles for Drug Delivery and Targeting. <em><i>Current Opinion in Solid State and Materials Science<\/i><\/em>2002, 6, 319-327.<\/p>\n<p>3. Pankhurst, Q. A.; Thanh, N. T. K.; <em><i>et al<\/i><\/em>. Progress in applications of magnetic nanoparticles in biomedicine. <em><i>Journal of Physics D: Applied Physics<\/i><\/em>2009, 42 (22), 224001.<\/p>\n<p>4. Hola, K.; Markova, Z.; <em><i>et al<\/i><\/em>. Tailored functionalization of iron oxide nanoparticles for MRI, drug delivery, magnetic separation and immobilization of biosubstances. <em><i>Biotechnol Adv<\/i><\/em>2015, 33 (6 Pt 2), 1162-76.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>With the improvement of nanotechnology, many advanced&nbsp;research paths have been opened up in different fields, and one&nbsp;of the most promising applications is drug delivery&nbsp;systems (DDSs) for cancer treatment. In the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[20],"tags":[609,608],"_links":{"self":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts\/1680"}],"collection":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/comments?post=1680"}],"version-history":[{"count":5,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts\/1680\/revisions"}],"predecessor-version":[{"id":1715,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/posts\/1680\/revisions\/1715"}],"wp:attachment":[{"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/media?parent=1680"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/categories?post=1680"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bocsci.com\/blog\/wp-json\/wp\/v2\/tags?post=1680"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}