Difference between revisions of "Team:NAIT Edmonton/Protocols"

 
(32 intermediate revisions by 2 users not shown)
Line 222: Line 222:
  
 
<center>
 
<center>
<h2> Go through our interactive experimental design flow chart! Many of our protocols are manufacturer specicfied; however, some are customized by us! Click on the flow chart boxes if the hand cursor appears to read more about our customized protocols. <br><br> PDFs of protocols can also be found <label class="btn" for="modal-1"><font color="#f96040">here</font>.</label></h2> </center>
+
<h2> Go through our interactive experimental design flow chart! Many of our protocols are manufacturer specicfied; however, some are customized by us! Click on the flow chart boxes if the hand cursor appears to read more about our customized protocols. <br><br> A PDF of all our protocols can also be found <a href="https://static.igem.org/mediawiki/2015/a/a2/NAIT_Protocols.pdf"><font color="#f96040">here.</font></a></h2> </center>
  
  
Line 288: Line 288:
 
     <div class="line1"></div>
 
     <div class="line1"></div>
  
     <label class="btn" for="AgaroseConfirmation"><div class="protocol"><font color="white">Run agarose gel electrophoresis to confirm that PCR was successful</font>
+
     <label class="btn" for="agarg"><div class="protocol"><font color="white">Run agarose gel electrophoresis to confirm that PCR was successful</font>
 
     </div></label>
 
     </div></label>
  
Line 314: Line 314:
 
     <div class="line1"></div>
 
     <div class="line1"></div>
  
     <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">
+
     <label class="btn" for="rSAP"><div class="protocol"><font color="#FFFFFF">
 
     Remove Phosphorylated Ends</font></div></label>
 
     Remove Phosphorylated Ends</font></div></label>
  
 
     <div class="line1"></div>
 
     <div class="line1"></div>
  
     <label class="btn" for="modal-1"><div class="protocol"> ...
+
     <label class="btn" for="ligate"><div class="protocol"><font color="#FFFFFF">Ligation of Vectors and Inserts</font>
 
     </div></label>
 
     </div></label>
  
Line 334: Line 334:
 
<div id="flowchart">
 
<div id="flowchart">
  
     <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">Introduce DNA to Competent Cells</font></div></label>
+
     <label class="btn" for="Transformation"><div class="protocol"><font color="#FFFFFF">Introduce DNA to Competent Cells</font></div></label>
 
+
    <div class="line1"></div>
+
 
+
    <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">Step 1:
+
    Blah blah blah, do this.</font></div></label>
+
 
+
    <div class="line1"></div>
+
 
+
    <label class="btn" for="modal-1"><div class="protocol">Step 1:
+
    Blah blah blah, do this.</div></label>
+
  
 +
   
 
</div>
 
</div>
  
Line 358: Line 349:
 
<div id="flowchart">
 
<div id="flowchart">
  
     <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">Literature has shown certain proteins   
+
     <label class="btn" for="colonyPCR"><div class="protocol"><font color="#FFFFFF">Colony PCR</font></div></label>
    inherently stain in colour.</font></div></label>
+
  
 
     <div class="line1"></div>
 
     <div class="line1"></div>
  
     <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">Step 1:
+
     <label class="btn" for="agarg"><div class="protocol"><font color="#FFFFFF">Agarose Gel Preparation</font></div></label>
    Blah blah blah, do this.</font></div></label>
+
  
 
     <div class="line1"></div>
 
     <div class="line1"></div>
  
     <label class="btn" for="modal-1"><div class="protocol">Step 1:
+
     <label class="btn" for="reviewa"><div class="protocol"><font color="#FFFFFF">Review Results</font></div></label>
    Blah blah blah, do this.</div></label>
+
  
 
</div>
 
</div>
Line 383: Line 371:
 
<div id="flowchart">
 
<div id="flowchart">
  
     <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">Literature has shown certain proteins   
+
     <label class="btn" for="proex"><div class="protocol"><font color="#FFFFFF">Protein Expression</font></div></label>
    inherently stain in colour.</font></div></label>
+
 
+
    <div class="line1"></div>
+
 
+
    <label class="btn" for="modal-1"><div class="protocol"><font color="#FFFFFF">Step 1:
+
    Blah blah blah, do this.</font></div></label>
+
  
 
     <div class="line1"></div>
 
     <div class="line1"></div>
  
     <label class="btn" for="modal-1"><div class="protocol">Step 1:
+
     <label class="btn" for="propure"><div class="protocol"><font color="#FFFFFF">Purification of Protien</font></div></label>
    Blah blah blah, do this.</div></label>
+
  
 +
   
 
</div>
 
</div>
  
Line 457: Line 439:
  
 
<ol type="1">
 
<ol type="1">
   <li>Level glass plates in the casting frame and place the frame within the casting stand.Ensure the plates are locked into  
+
   <li>Level glass plates in the casting frame and place the frame within the casting stand. Ensure the plates are locked into  
 
       place.</li>   
 
       place.</li>   
 
   <li>Place the following solutions in a 50 mL falcon tube:<br>
 
   <li>Place the following solutions in a 50 mL falcon tube:<br>
Line 519: Line 501:
  
 
     <li>Prepare samples that will be ran in the gel electrophoresis.</li>
 
     <li>Prepare samples that will be ran in the gel electrophoresis.</li>
     <li>Mix 15μl of each sample with 5μl of sample buffer solutiom. A 3 to 1 ratio is used. A maximum of 30μl can be inserted  
+
     <li>Mix 15μl of each sample with 5μl of sample buffer solution. A 3 to 1 ratio is used. A maximum of 30μl can be inserted  
 
         into each well.</li>
 
         into each well.</li>
 
     <li>Place glass plates in the electrode assembly and into the tank cell.</li>
 
     <li>Place glass plates in the electrode assembly and into the tank cell.</li>
Line 539: Line 521:
  
 
     <center><h1>Silver Stain Plus Protocol</h1></center>
 
     <center><h1>Silver Stain Plus Protocol</h1></center>
   <center><img src="http://www.bio-rad.com/webroot/web/images/lsr/products/electrophoresis/product_detail/global/lsr_silver_stain_plus_kit.jpg"></center>
+
   <center><img src="https://static.igem.org/mediawiki/2015/a/a4/NAIT_SilverStainBottles.jpeg" width="500px"></center>
 
     <br><br>
 
     <br><br>
 
     <ol type="1">
 
     <ol type="1">
Line 605: Line 587:
 
     <center><h1>PCR Master Mix Protocol</h1></center><br>
 
     <center><h1>PCR Master Mix Protocol</h1></center><br>
  
    <center><img src="https://upload.wikimedia.org/wikipedia/commons/8/8b/Overlap_Extension_PCR.png" width="750px"></center> <br>
 
 
     <p><b>Before beginning, ensure all reaction components and properly thawed and mixed.</b></p><br>
 
     <p><b>Before beginning, ensure all reaction components and properly thawed and mixed.</b></p><br>
 
     <p>Calculate the required volumes of each component based on the following table:</p><br>
 
     <p>Calculate the required volumes of each component based on the following table:</p><br>
Line 756: Line 737:
  
 
         <center><h1>Digestion of Vectors and Inserts</h1></center><br><br>
 
         <center><h1>Digestion of Vectors and Inserts</h1></center><br><br>
       <center>Two enzymes are needed in order to cut the DNA stands at specific restriction sites</center>
+
       Two enzymes are needed in order to cut the DNA stands at specific restriction sites<br>
         <center>1. Find the protocol of restriction enzymes being used</center>
+
         1. Find the protocol of restriction enzymes being used<br><br>
         <center>Use the </center>
+
         2. Mix the following components<br>
 +
<center>
 +
<table class="tg">
 +
<tr>
 +
<strong>
 +
<th class="tg-hgcj">Component</th>
 +
<th class="tg-hgcj">Amount</th>
 +
</strong>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Enzyme 1</td>
 +
<td class="tg-s6z2">1µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Enzyme 2</td>
 +
<td class="tg-s6z2">1µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">DNA</td>
 +
<td class="tg-s6z2">1µg</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Buffer</td>
 +
<td class="tg-s6z2">5µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Nuclease Free H<sub>2</sub>O</td>
 +
<td class="tg-s6z2">Up to 50µL</td>
 +
</tr>
 +
 
 +
</table>
 +
 
 +
*Ratio of enzymes to DNA is 1:1 and water is added to maintain the concentration based on each enzyme
 +
<br><br>
 +
3. Let reaction occur for 1 hour
 +
 
 +
 
 
<center></center>
 
<center></center>
 
<center></center>
 
<center></center>
Line 766: Line 783:
  
  
 +
<input class="modal-state" id="rSAP" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="rSAP"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>rSAP Protocol</h1></center>
 +
      <center><h2>Removal of Phosphorylated Ends<br>Preformed after digestion of psB1C3 </h2></center>
 +
<br>
 +
Protocol<br>
 +
1. Prepare sample using the following<br>
 +
<table class="tg">
 +
<tr>
 +
<strong>
 +
<th class="tg-hgcj">Component</th>
 +
<th class="tg-hgcj">Amount</th>
 +
</strong>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">rSAP</td>
 +
<td class="tg-s6z2">1 unit</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">DNA</td>
 +
<td class="tg-s6z2">1pmol of DNA ends</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Nuclease Free H<sub>2</sub>O</td>
 +
<td class="tg-s6z2">Up to 20µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">CutSmart Buffer(10X)*</td>
 +
<td class="tg-s6z2">2µL</td>
 +
</tr>
 +
 +
</table>
 +
*Provided with rSAP<br>
 +
Total volume should equal 20 µL<br><br>
 +
2. Incubate at 37°C for 30 minutes<br>
 +
3. Stop the reaction by heat inactivation ay 65°C for 5 minutes
 +
  </div>
 +
</div>
 +
 +
 +
 +
<input class="modal-state" id="ligate" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="ligate"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Ligation of Vectors and Inserts</h1></center>
 +
      <br>
 +
1. Set up the following reaction mixture on ice:
 +
<table class="tg">
 +
<tr>
 +
<strong>
 +
<th class="tg-hgcj">Component</th>
 +
<th class="tg-hgcj">20µL Reaction</th>
 +
</strong>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">10X T4 Ligase Buffer</td>
 +
<td class="tg-s6z2">2µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Vector DNA (4kb)</td>
 +
<td class="tg-s6z2">50ng (0.020pmol)</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Insert DNA (1kb)</td>
 +
<td class="tg-s6z2">37.5ng (0.60pmol)</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Nuclease Free H<sub>2</sub>O</td>
 +
<td class="tg-s6z2">Up to 20µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">T4 DNA Ligase</td>
 +
<td class="tg-s6z2">1µL</td>
 +
</tr>
 +
 +
</table>
 +
 +
 +
 +
 +
2. Gently mix the reaction by pipetting up and down and microfuge briefly<br>
 +
3. For cohesive ends, incubate at 16°C overnight or at room temperature for 10 minutes<br>
 +
4. For blunt ends or single base overhangs, incubate at 16°C overnight or room temperature for 2 hours<br>
 +
5. Heat inactivate at 65°C for 10 minutes<br>
 +
6. Chill on ice and transform 1-5 µL if the reaction into 50 µL competent Cells<br>
 +
 +
 +
  </div>
 +
</div>
 +
 +
<input class="modal-state" id="Transformation" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="Transformation"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Transforming the Bacteria</h1></center><br><br>
 +
1. Thaw tube of BL21 (DE3) competent E. coli cells on ice for 10 min<br>
 +
2. Add 1-5 µL containing 1pg-100ng of plasmid DNA to the cell mixture. Carefully flick the tube 4-5 times to mix cells and DNA. <font color="#FF0000">(DO NOT VORTEX)</font><br>
 +
3. Place the mixture on ice for 30 minutes<font color="#FF0000"> (DO NOT MIX)</font><br>
 +
4. Heat shock at exactly 42°C for exactly 10 seconds. <font color="#FF0000"> (DO NOT MIX)</font><br>
 +
5. Place on ice for 5 Minutes.<font color="#FF0000"> (DO NOT MIX)</font><br>
 +
6. Pipette 950µL of room temperature SOC into the mixture.<br>
 +
7. Place at 37°C for 60 minutes. Shake vigorously (250RPM) or rotate<br>
 +
8. Warm selection plates to 37°C<br>
 +
9. Mix the cells thoroughly by flicking the tube and inverting, then perform several 10-fold serial dilutions in SOC<br>
 +
10. Spread 50-100µL of each dilution onto a selection plate and incubate overnight at 37°C. alternatively, incubate at 30°C for 24-36 hours or 25°C for 48 hours<br>
 +
 +
 +
  </div>
 +
</div>
 +
 +
 +
<input class="modal-state" id="colonyPCR" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="colonyPCR"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Colony PCR</h1></center>
 +
      <center><h2>KAPA HiFi Hotstart</h2></center><br>
 +
 +
1. Prepare the PCR master mix using the following<br>
 +
<table class="tg">
 +
<tr>
 +
<strong>
 +
<th class="tg-hgcj">Component</th>
 +
<th class="tg-hgcj">50µL Reaction*</th>
 +
<th class="tg-hgcj">Final Concentration</th>
 +
</strong>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">PCR Grade H<sub>2</sub>O</td>
 +
<td class="tg-s6z2">Up to 50µL</td>
 +
<td class="tg-s6z2">N/A</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">2X KAPA HiFi HS</td>
 +
<td class="tg-s6z2">25µL</td>
 +
<td class="tg-s6z2">1X</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">10µM Forward Primer**</td>
 +
<td class="tg-s6z2">1.5µL</td>
 +
<td class="tg-s6z2">0.3µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">10µM Reverse Primer**</td>
 +
<td class="tg-s6z2">1.5µL</td>
 +
<td class="tg-s6z2">0.3µL</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Colony DNA</td>
 +
<td class="tg-s6z2">As Required</td>
 +
<td class="tg-s6z2">As Required</td>
 +
</tr>
 +
 +
</table>
 +
* Reaction Volumes may be adjusted between 10 - 50 µL<br>
 +
** Provided by iGem<br><br>
 +
2. Transfer the appropriate volumes of PCR master mix and colony DNA to individual PCR tubes<br>
 +
3. Cap or seal individual reactions.<br>
 +
4. Mix and centrifuge briefly.<br>
 +
5. Preform PCR using the following cycle protocol<br>
 +
<table class="tg">
 +
<tr>
 +
<strong>
 +
<th class="tg-hgcj">Step</th>
 +
<th class="tg-hgcj">Temperature</th>
 +
<th class="tg-hgcj">Duration</th>
 +
<th class="tg-hgcj">Cycles</th>
 +
</strong>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Initial Denaturing</td>
 +
<td class="tg-s6z2">95°C</td>
 +
<td class="tg-s6z2">3 min</td>
 +
<td class="tg-s6z2">1</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Denaturing</td>
 +
<td class="tg-s6z2">98°C</td>
 +
<td class="tg-s6z2">20 sec</td>
 +
<td class="tg-s6z2">25</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Annealing</td>
 +
<td class="tg-s6z2">61°C</td>
 +
<td class="tg-s6z2">30 sec</td>
 +
<td class="tg-s6z2">25</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Initial Denaturing</td>
 +
<td class="tg-s6z2">72°C</td>
 +
<td class="tg-s6z2">15 sec</td>
 +
<td class="tg-s6z2">25</td>
 +
</tr>
 +
<tr>
 +
<td class="tg-s6z2">Initial Denaturing</td>
 +
<td class="tg-s6z2">72°C</td>
 +
<td class="tg-s6z2">1 min</td>
 +
<td class="tg-s6z2">1</td>
 +
</tr>
 +
 +
</table>
 +
 +
 +
 +
  </div>
 +
</div>
 +
 +
 +
 +
<input class="modal-state" id="agarg" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="agarg"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Agarose Gel Protocol</h1></center>
 +
      <br>
 +
1. Mix 99mL of TA buffer with 1g of Agarose and mix on a hotplate until boil<br>
 +
2. Add 10µL of ethidium bromide after boil and pour into Agarose casting tray<br>
 +
3. Insert comb at desired depth<br>
 +
4. Let stand until gel is formed<br>
 +
5. Add samples into well of desire on Agarose gel<br>
 +
6. Run gel at 70V for desired time<br><br>
 +
 +
<h2>Sample Prep</h2>
 +
 +
1. Add 10µL sample with 2µL sample buffer for each well. ~1:5 ratio<br>
 +
<strong>NOTE:</strong> allow for excess reagents if needed
 +
 +
 +
 +
  </div>
 +
</div>
 +
 +
 +
<input class="modal-state" id="reviewa" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="reviewa"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Review Results</h1></center><br><br>
 +
      1. Any samples under 339 base pairs in length were determined to be unsuccessful as they had no insert
 +
 +
  </div>
 +
</div>
 +
 +
 +
 +
 +
<input class="modal-state" id="propure" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="propure"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Protein Purification under Denaturing</h1></center>
 +
      <center><h2>Ni-NTA Spin Kit</h2></center>
 +
<strong>NOTE:</strong> due to dissociation of urea used pH values of buffers will need to be check and if necessary adjusted <br>
 +
<strong>NOTE:</strong> this protocol is suitable for use with frozen cell pellets. Cell pellets frozen for at least 30 minutes at -20°C can be lysed by re-suspending in lysis buffer and adding Benzonase Nuclease (3units/mL culture volume). Fresh pellets require sonication or homogenization in addition. To the addition of 3 units/mL culture volume Benzonase Nuclease and 1mg/mL culture volume lysozyme.<br><br><br>
 +
 +
1. Thaw cells for 15 minutes and re-suspend in 700µL buffer B-7M urea and add 3 units/mL culture volume Benzonase Nuclease <br>
 +
<strong>NOTE:</strong> Cells from 5 mL cultures are usually used, but culture volume used depends on protein expression level. Re-suspending pellet in 700µL buffer will allow recovery volume of cleared lysate of approx. 600µL<br><br>
 +
2. Incubate cells with agitation for 15 minutes at room temperature. Solution should become translucent when lysis is complete. <br>
 +
<strong>NOTE:</strong> buffer B is the preferred lysis buffer, as the cell lysate can be analyzed directly by SDS-PAGE. If the cells or the protein do not solubilize buffer A must be used.<br><br>
 +
3. Centrifuge lysate at 12,000xg for 15-30 minutes at room temperature to pellet the cellular debris. Collect supernatant.<br>
 +
<strong>NOTE:</strong> save 20µL of the cleared lysate for SDS-PAGE analysis<br><br>
 +
4. Equilibrate a Ni-NTA spin column with 600µL buffer B-7M urea. Centrifuge for 2 minutes at 890xg (2900RPM).<br>
 +
<strong>NOTE:</strong> the spin columns should be centrifuged with an open lid to ensure that the centrifugation step is completed after 2 minutes.<br><br>
 +
5. Load up to 600µL of the cleared lysate supernatant containing the GxHis-tagged protein onto a pre-equilibrated Ni-NTA spin column. Centrifuge for 5 minutes at 270xg (1600RPM), and collect the flow-through<br>
 +
<strong>NOTE:</strong> to ensure sufficient binding, it is important not to exceed 270xg (1600RPM) when centrifuging Ni-NTA spin columns<br><br>
 +
6. Wash Ni-NTA spin column with 600µL buffer C. Centrifuge for 2 minutes at 890xg (2900RPM)<br>
 +
7. Repeat step 6<br>
 +
8. Elute the protein with 200µL buffer E. Centrifuge for 2 minutes at 890xg (2900RPM) and collect the elute<br>
 +
9. Repeat step 8<br>
 +
 +
 +
  </div>
 +
</div>
 +
 +
<input class="modal-state" id="proex" type="checkbox" />
 +
<div class="modal">
 +
  <label class="modal__bg" for="proex"></label>
 +
  <div class="modal__inner">
 +
 +
        <center><h1>Protein expression using BL21(DE3)</h1></center>
 +
1. Transform expression plasmid into BL21 (DE3). Plate on antibiotic selection plates and incubate overnight at 37°C<br>
 +
2. Re-suspend a single successful colony (determined from validating the transformation in 10mL liquid culture with antibiotic<br>
 +
3. Incubate at 37°C until optical density reaches an absorbance of 0.4-0.8<br>
 +
4. Induce with 4 or 40µL of 100mM stock of IPTG (final concentration of 40 or 400µM) and induce for 3 to 5 hours at 37°C <br>
 +
5. For large scale, inoculate 1L of liquid medium (with anitboitic) with freshly grown colony or 10 mL of freshly grown culture. Incubate at 37°C until optical density reaches an absorbance of 0.4-0.8. Add 40 or 400µM IPTG and express protein using optimal time and temperature determined in small scale trial<br>
 +
 +
 +
  </div>
 +
</div>
 
<!----------------------------------------------------END MODALS--------------------------------------------------------->
 
<!----------------------------------------------------END MODALS--------------------------------------------------------->
  

Latest revision as of 11:08, 18 September 2015

Team NAIT 2015

Experimental Design

Go through our interactive experimental design flow chart! Many of our protocols are manufacturer specicfied; however, some are customized by us! Click on the flow chart boxes if the hand cursor appears to read more about our customized protocols.

A PDF of all our protocols can also be found here.

Theorizing our Sequences
Literature has shown certain proteins inherently stain in colour.
Looked up characteristics of said proteins
Isolated and identified the unique characteristics of said proteins so that we can manually write our own sequences and generate custom proteins.
Writing our Sequences
Went down to base pair level and wrote out our sequences with the defining characteristics identified in literature.
PCR
Digestion and Ligation
Transforming Bacteria
Validating the Transformation
Protein Isolation and Purification
SDS PAGE and Silver Staining