{"id":20120,"date":"2021-03-09T11:38:16","date_gmt":"2021-03-09T05:53:16","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=20120"},"modified":"2021-03-09T11:51:16","modified_gmt":"2021-03-09T06:06:16","slug":"new-biosensor-that-measures-h2o2-concentrations-near-cell-membranes","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/new-biosensor-that-measures-h2o2-concentrations-near-cell-membranes\/","title":{"rendered":"New biosensor that measures H2O2 concentrations near cell membranes"},"content":{"rendered":"\n

Researchers have developed a sensor that measures hydrogen peroxide concentrations (H2<\/sub>O2<\/sub>) of  in near cell membranes, with nanometer-resolution. <\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Biosensors and Bioelectronics: a successful test of a sensor<\/a> has the potential to become a tool for new cancer therapies, according to Leonardo Puppulin from Nano Life Science Institute (WPI-NanoLSI), Kanazawa University.<\/p>\n\n\n\n

The biosensor is based on a method called surface-enhanced Raman spectroscopy (SERS). The principle derives from Raman spectroscopy, in which differences between the incoming and the outcoming frequencies of laser light irradiated onto a sample are analyzed.  <\/p>\n\n\n\n

Several processes in the human body are regulated by biochemical reactions involving hydrogen peroxide (H2<\/sub>O2<\/sub>).  Although it can act as a \u2018secondary messenger\u2019, relaying or amplifying certain signals between cells, H2<\/sub>O2<\/sub> is generally toxic because of its oxidant character.  <\/p>\n\n\n\n

The latter means that it converts (oxidizes) biochemical molecules like proteins and DNA.  The oxidizing property of H2<\/sub>O2<\/sub> is of potential therapeutic relevance for cancer, though: deliberately causing tumor cells to increase their H2<\/sub>O2<\/sub> concentration would be a way to destroy them. <\/p>\n\n\n\n

In light of this, but also for monitoring pathologies associated with H2<\/sub>O2<\/sub> overproduction, it is crucial to have a means to reliably quantify hydrogen peroxide concentrations in the extracellular environment.  <\/p>\n\n\n\n

The biosensor consists of a gold nanoparticle with organic molecules attached to it.  The whole cluster is designed so that it anchors easily to the outside of a cell\u2019s membrane, which is exactly where the hydrogen peroxide molecules to be detected are.  <\/p>\n\n\n\n

As attachment molecules, the scientists used a compound called 4MPBE, known to have a strong Raman scattering response: when irradiated by a laser, the molecules consume some of the laser light\u2019s energy.  <\/p>\n\n\n\n

By measuring the frequency change of the laser light, and plotting the signal strength as a function of this change, a unique spectrum is obtained \u2014 a signature of the 4MPBE molecules.  <\/p>\n\n\n\n

When a 4MPBE molecule reacts with a H2<\/sub>O2<\/sub> molecule, its Raman spectrum changes.  Based on this principle, by comparing Raman spectra, Puppulin and colleagues were able to obtain an estimate of the H2<\/sub>O2<\/sub> concentration near the biosensor.<\/p>\n\n\n\n

After developing a calibration procedure for their nanosensor \u2014 relating the H2<\/sub>O2<\/sub> concentration to a change in Raman spectrum in a quantitative way is not straightforward \u2014 the scientists were able to produce a concentration map with a resolution of about 700 nm for lung cancer cell samples.  Finally, they also succeeded in extending their technique to obtain measurements of the H2<\/sub>O2<\/sub> concentration variation across cell membranes.<\/p>\n\n\n\n

Puppulin and colleagues conclude that their \u201cnovel approach may be useful for the study of actual H2<\/sub>O2<\/sub> concentrations involved in cell proliferation or death, which are fundamental to fully elucidate physiological processes and to design new therapeutic strategies.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"

Researchers have developed a sensor for measuring hydrogen peroxide concentrations (H2O2) of in near cell membranes, with nanometer-resolution. <\/p>\n","protected":false},"author":2,"featured_media":20121,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[122,14],"tags":[],"class_list":["post-20120","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-chemistry","category-innovation"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",1100,619,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-200x200.jpg",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-675x380.jpg",675,380,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-768x432.jpg",750,422,true],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-675x380.jpg",675,380,true],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",1100,619,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",1100,619,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",1100,619,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",870,490,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",600,338,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",600,338,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-760x490.jpg",760,490,true],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-550x360.jpg",550,360,true],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin-95x65.jpg",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",640,360,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",96,54,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2021\/03\/thumbnail_pupplin.jpg",150,84,false]},"author_info":{"info":["RevoScience"]},"category_info":"Chemistry<\/a> Innovation<\/a>","tag_info":"Innovation","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/20120","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=20120"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/20120\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/20121"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=20120"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=20120"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=20120"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}