Biofilm Development Suggestions?

[BfmHobo]

Hey Ya'll

 

I am new to the forum and was wondering if I could get some advice on biofilm development on stainless steel coupons.

 

I want to test several different industrial sanitizers on relatively short time developed biofilms but am having trouble quantifying them apart from planktonic cells.

 

What is a good way to rinse off planktonic cells carefully enough but enough to make certain my plate counts are based on cells that adhered to the surface??

 

Thanks for any sort of suggestions

[CharonY]

Do you mean actual biofilm (for which various visualization techniques including stains exist), or just adherence? While adherence is the first step, it is not necessarily the same.

Assuming the goal is the measurement of simply adherent cells, it depends on how precise you want to be. As a basic approach one applies a defined amount and identical amount of shear forces to each sample in order to remove bacteria who have surface interactions forces below that given amount. Depending on what you have at hand, centrifugation, use of defined water jets/flows, micromanipulators and AFM are options.

 

The point being that there is no absolute distinction between adherent and planctonic cells. There will always be some level of force, depending on substrate and cellular surface properties (such as charge, morphology etc.). Typically, for each question the design has to be altered. E.g. looking at adherence under a no-flow system would be treated differently (as cells have a long time to settle) than during some kind of active shear forces acting on the cells.

Edited September 10, 2014 by CharonY