Through the week, I did a little research on Oak Ridge tubes for centrifugation of my samples. The tubes must be rated to withstand the action of the phenol chloroform solution. Not everything is up to the task of this. In the lab I found Oak Ridge tubes that were labeled PPCO and needed to find out if they would be appropriate. As it turns out, they are. PPCO refers to one of the constituent compounds of the tube: Polypropylene Copolymer. This is the stuff that is resilient enough to handle the phenol.
This is a screen shot from a pdf of Nalgene's catalogue
available at http://www.catalogus.de/pdf/30/centrifugecatintl.pdf
Also, I noted that the SDS component solution for my lysis buffer had settled out of solution and essentially crystalized. This was rather worrisome for me. I know that I had followed the mixing and storage instructions to the letter. I was worried that this would in fact be a solution that I would have to prepare and use in the same day. Coupling this with a rather long extraction protocol could be very problematic! I used a magnetic stirrer on a hotplate to mix the solution for approximately 1/2 hour to no result. I was very hesitant to heat it while mixing as I didn't want to take the chance of denaturing any of the active ingredients within. Well, until I realized I will be heating it to 50 degrees C in my protocol! I applied very minimal heat while mixing and within 15 to 20 minutes there were no traces of precipitants left!
Matthew,
ReplyDeleteI'm really impressed with your courage and extensive knowledge about chemistry. Apparently, you are carefully going through your experiment and examine each step to avoid errors. I guess you are spending a lot of time to read about each component you use and study the reactions of different materials with each other. I hope that you will finish the project successfully and learn from working in the lab.
Thanks,
Maha