7 replies to this topic

[autoclave]

Hi Everyone !

I need to detach a biofilm from a surface which will then be processed to extract DNA. I am just wondering if sonication will be enought to remove all attached bacteria. The surface the biofilm will be attached to is a thin clay tablet. Any ideas?

Cheers

[GeorgeWolff]

Why not remove it with a tool - like a sterile spatula?

[autoclave]

GeorgeWolff, on May 1 2009, 11:51 PM, said:

Why not remove it with a tool - like a sterile spatula?

I believe that removing it with a sterile spatula would still perhaps leave bacteria attached to the surface. In very thin biofilms, on the other hand, I guess it would not work (¿?).

[phage434]

I would include a sample of the clay tablet in the lysis reaction.  Chemistry will remove things that mechanical disruption will not.  A phenol/chloroform extraction would likely remove most anything organic.

[autoclave]

phage434, on May 2 2009, 02:30 PM, said:

I would include a sample of the clay tablet in the lysis reaction.  Chemistry will remove things that mechanical disruption will not.  A phenol/chloroform extraction would likely remove most anything organic.

thanks for your reply. should the phenol/chloroform extraction of the biofilm interfere with subsequent DNA extraction from it using e.g., a DNA isolation kit?

cheers

[hanming86]

i would go with georgewolff's method of using a spatula to scrap the biofilm out. It should get like most of the thing. even if it's a thin biofilm u will still get something. It's kinda like u know scraping bacteria off agar plate. the more distance u scrap the "thicker" the cell mass get. Same theory .

[archercr]

I've read of scraping with a spatula, but in my protocol, we sonicate in a water bath.  You place a steel tray inside the water bath and the plate inside the dry tray.  the vibrations from the water transfer through the tray to the plate, causing the bacteria to loosen.

[microgirl]

I just got an email from MoBio about their new kit:
http://www.mobio.com...es/biofilm.html
I don't do biofilms, so I didn't look into it, but maybe it has some suggestions.