Transport limitation by reaction-diffusion interaction

Another explanation for reduced biocide penetration into biofilms is the interaction between biocide and biofilm constituents, including cells and EPS a result would be depletion of the antimicrobial compound in the biofilm interior. The underlying mechanisms may be chemical reactions of the biocide with, or sorption to, the biofilm components or the enzymatic degradation of the biocide, resulting in a restricted penetration of the biocide into the biofilms (reaction-diffusion interaction mechanism). 

Aldehydes [II, 2.] react with amino acid residues of proteins, which may be a substantial fraction of the EPS. The reaction of glutaraldehyde with extracellular proteins in P. fluorescens biofilms was supposed to reduce the antimicrobial action of the bioeide (Pereira and Vieira, 2001). 

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