Difference between revisions of "Template:Team:TU Eindhoven/Experimental Approach HTML"

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With today’s technology and knowledge, ground-breaking drug discoveries are at the forefront of the medical sciences and society. For many diseases, however, the foundation of curing lies not exclusively in the availability of these sophisticated drugs, but rather in an accurate and early diagnosis. For colon cancer, for example, the survival rate of patients diagnosed at the early stage is 90%, whereas the survival rate of patients diagnosed in the critical stage is a mere 13% <a name="reft1" href="#ref1" class="textanchor">[1]</a>. Similar figures hold for many more diseases. <image src="https://static.igem.org/mediawiki/2015/8/87/TU_Eindhoven_Ingeklapt.png" id="spoilerbutton1" class="spoilerbutton" onclick="changeImage(this.id, this.value)" /><br /><div class="spoiler" id="spoiler1">
 
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Without diving too much in the details, one can see that a simple Google search already yields many reports underlining the importance of an early detection of disease for <a href=' http://www.alz.org/documents_custom/final_world_alz_report_2011_summary.pdf' target='_blank'>Alzheimer’s disease</a> and <a href='http://www.amcp.org/data/jmcp/June04Supplement1.pdf' target='_blank'>Multiple Sclerosis</a>.
 
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Making an early biomedical diagnosis is thus often of vital importance.
 
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Such diagnoses can be made in multiple ways. Often, they are made using analytical instruments, such as MRI scanners, NMR and mass spectrometry. These instrumentation methods can provide rich information on both the structure as well as the concentration of disease markers <a name="reft2" href="#ref2" class="textanchor">[2]</a>. Even though these instruments can come to a sound diagnosis, they have a profound disadvantage: samples often need to be pre-treated and diagnoses cannot be made on-site, leading to prolonged processing times.
 
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Due to this disadvantage, biosensors have found their way into society. In contrast to analytical instruments, biosensors can quickly diagnose a disease, can be used on-site and are often easy to use. iGEM TU Eindhoven has devised to develop a universal platform for biosensors. The designed platform is constructed from three major elements, being the recognition element which is used to detect disease markers, the signaling components which translate the detection into a measurable signal and a scaffold which joins the signaling components and recognition elements. An overview of the elements is presented below.
 
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Revision as of 13:57, 4 August 2015





Experimental approach



To test the viability of the designed system, we have designed a number of experiments. These experiments are conducted to verify whether the individual elements of our device work. An overview of the experiments is given below.

Verifying the click reaction


A vital aspect of our device is clicking the aptamers to the membrane proteins. For this click, we madeuse of the exact same click chemistry used by iGEM TU Eindhoven 2014. iGEM TU Eindhoven 2014 has used the click reaction N-terminally. To analyze whether the localization of the azide-functionalized amino acid within the loops of OmpX impedes the click reaction, we clicked a DBCO-functionalized fluorophore (TAMRA) to the outer membrane proteins. After some washing steps and spinning down, we expected the cells to remain fluorescent. To analyze the fluorescence at the single-cell level, we measured cells using the Fluorescence-Activated Cell Sorter (FACS). Martijn van Rosmalen gave us a clarifying FACS introduction to get us started and Wiggert Altenburg assisted us with the first experiments.

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