Difference between revisions of "Team:Paris Bettencourt/Hardware setup"

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<div class=textbody>
 
<div class=textbody>
 
<h3> Gel Choice </h3>
 
<h3> Gel Choice </h3>
−
The optical properties of a gel depends on the gel type, its concentration and the nutrient source. <br> <br>
+
The optical properties of a gel depend on the gel type, its concentration and the nutrient source. <br> <br>
 
</div>
 
</div>
 
<div class=text2>
 
<div class=text2>
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−
     <td>Key advantage</td>
+
     <th>Key advantage</th>
 
     <td>Solidifies at room temperature <br> by adding calcium ion</td>  
 
     <td>Solidifies at room temperature <br> by adding calcium ion</td>  
 
     <td>Most ubiquitous microbiology gel</td>
 
     <td>Most ubiquitous microbiology gel</td>
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   <tr>
 
   <tr>
 
  <th>Recommended concentration</th>
 
  <th>Recommended concentration</th>
−
<th>1.75-4% </th>
+
<td>1.75-4% </td>
−
<th>1-1.5% </th>
+
<td>1-1.5% </td>
−
<th>0.15-0.25% </th>
+
<td>0.15-0.25% </td>
 
   </tr>
 
   </tr>
  
 
<tr>
 
<tr>
 
<th>Melting-Gelling Point</th>
 
<th>Melting-Gelling Point</th>
−
<th>NA</th>
+
<td>NA</td>
−
<th>0.5%:85-20C <br>1%:90-35C</th>
+
<td>0.5%:85-20C <br>1%:90-35C</td>
−
<th>0.5%:65-15 <br>1%:100-35C</th>
+
<td>0.5%:65-15 <br>1%:100-35C</td>
 
  </tr>
 
  </tr>
 
<tr>
 
<tr>
 
<th>Key disadvantage</th>
 
<th>Key disadvantage</th>
−
<th>Properties depend on calcium ion diffusion<br>which is hard to control</th>
+
<td>Properties depend on calcium ion diffusion<br>which is hard to control</td>
−
<th>High absorbance</th>
+
<td>High absorbance</td>
−
<th>Melts less well than agar</th>
+
<td>Melts less well than agar</td>
 
</tr>
 
</tr>
  
 
<tr>
 
<tr>
 
<th>Concentration studied</th>
 
<th>Concentration studied</th>
−
<th>1% with LB</th>
+
<td>1% with LB</td>
−
<th>1% with LB</th>
+
<td>1% with LB</td>
−
<th>1% & 0.5% with LB</th>
+
<td>1% & 0.5% with LB</td>
 
</tr>
 
</tr>
  
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<div class=text2> <div class=text2right>
 
<div class=text2> <div class=text2right>
 
<section>  
 
<section>  
−
The optical properties of a gel depends on the gel type, its concentration and the nutrient source. <br> <br>
+
The optical properties of a gel depend on the gel type, its concentration and the nutrient source. <br> <br>
 
It is best to use a low gel concentration to reduce absorbance. Conveniently some gels have a higher melting point than solidifying point. This hysteresis phenomenon means that the gel concentration can be lowered and still be kept at in a solid state at 37C by pre-cooling them (to 6-8C) prior to warm incubation.<br><br>
 
It is best to use a low gel concentration to reduce absorbance. Conveniently some gels have a higher melting point than solidifying point. This hysteresis phenomenon means that the gel concentration can be lowered and still be kept at in a solid state at 37C by pre-cooling them (to 6-8C) prior to warm incubation.<br><br>
 
</section>
 
</section>
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<div class=text2left><img src="https://static.igem.org/mediawiki/2017/2/27/PB_PC_LB_M9_Abosrbance.jpeg"></div>
 
<div class=text2left><img src="https://static.igem.org/mediawiki/2017/2/27/PB_PC_LB_M9_Abosrbance.jpeg"></div>
 
<div class=text2right>
 
<div class=text2right>
−
Alginate gelling is induced by calcium ions which crosslink gelling polymers at room temperature. To get a homogenous gel, calcium ions cannot be mixed with an Alginate solution but must diffuse from an underlying calcium source (1). Since the optical properties of Alginate depends on the amount of crosslinking, they ultimately depend on calcium diffusion which is a difficult parameter to control. It is important to note that keeping the same diffusion conditions (time, temperature, calcium source concentration etc.) is necessary to maintain identical alginate optical properties between experiments. In addition to the gelling agent, the nutrient source also impacts light absorbance. Conveniently, LB shows less absorbance than M9 media at most visible wavelengths and was therefore added to our gels for our study.
+
Alginate gelling is induced by calcium ions which crosslink gelling polymers at room temperature. To get a homogenous gel, calcium ions cannot be mixed with an Alginate solution but must diffuse from an underlying calcium source (1). Since the optical properties of Alginate depend on the amount of crosslinking, they ultimately depend on calcium diffusion which is a difficult parameter to control. It is important to note that keeping the same diffusion conditions (time, temperature, calcium source concentration etc.) is necessary to maintain identical alginate optical properties between experiments. In addition to the gelling agent, the nutrient source also impacts light absorbance. Conveniently, LB shows less absorbance than M9 media at most visible wavelengths and was therefore added to our gels for our study.
 
   
 
   
 
</div>
 
</div>

Revision as of 15:46, 31 October 2017

Light Signalling in Gels

OPTIC MODEL

Introduction

Medusa aims at optically controlling bacteria immobilized in a gel by targetting them with two intersecting lasers. Two questions are important to address to achieve this goal:

How far can a laser go in a gel?

What resolution can the laser achieve?

We present in this page our study of the optical properties of commonly used culture gels. We show that it is possible to obtain a clean light signal even at gel depths greater than 10cm.

Gel Choice

The optical properties of a gel depend on the gel type, its concentration and the nutrient source.

Alginate Agar Gelrite
Key advantage Solidifies at room temperature
by adding calcium ion		 Most ubiquitous microbiology gel Low absorbance
Recommended concentration 1.75-4% 1-1.5% 0.15-0.25%
Melting-Gelling Point NA 0.5%:85-20C
1%:90-35C		 0.5%:65-15
1%:100-35C
Key disadvantage Properties depend on calcium ion diffusion
which is hard to control		 High absorbance Melts less well than agar
Concentration studied 1% with LB 1% with LB 1% & 0.5% with LB
Table 1: Gel Included in this Study
The optical properties of a gel depend on the gel type, its concentration and the nutrient source.

It is best to use a low gel concentration to reduce absorbance. Conveniently some gels have a higher melting point than solidifying point. This hysteresis phenomenon means that the gel concentration can be lowered and still be kept at in a solid state at 37C by pre-cooling them (to 6-8C) prior to warm incubation.

Alginate gelling is induced by calcium ions which crosslink gelling polymers at room temperature. To get a homogenous gel, calcium ions cannot be mixed with an Alginate solution but must diffuse from an underlying calcium source (1). Since the optical properties of Alginate depend on the amount of crosslinking, they ultimately depend on calcium diffusion which is a difficult parameter to control. It is important to note that keeping the same diffusion conditions (time, temperature, calcium source concentration etc.) is necessary to maintain identical alginate optical properties between experiments. In addition to the gelling agent, the nutrient source also impacts light absorbance. Conveniently, LB shows less absorbance than M9 media at most visible wavelengths and was therefore added to our gels for our study.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.

SECOND MODEL

your text
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.

THIRD MODEL

your text
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.
RNA is a light cost nucleotide material in the cell, We aim to recreate RNA agglomerations as formed in mammalian cells with triple repeat disorders, which show liquid phase separation, forming a organelle-like vesicle, where local concentrations of enzymes can be created.


Centre for Research and Interdisciplinarity (CRI)
Faculty of Medicine Cochin Port-Royal, South wing, 2nd floor
Paris Descartes University
24, rue du Faubourg Saint Jacques
75014 Paris, France
bettencourt.igem2017@gmail.com