Quick and simple colorimetric analytical techniques were developed to monitor functionalization of surfaces with quaternary amine bearing polymers as complementary qualitative tests to the traditionally used antimicrobial test protocols. First, an established antimicrobial quaternary ammonium salt (QAS) was chosen as a probe compound and an acrylol functional group was introduced (acrylol-QAS) to facilitate its polymerization with acrylic monomers. Surface graft polymerization was carried out with methyl methacrylate (MMA) and acrylol-QAS on cotton fabric surface. The success of graft polymerization, durability after repetitive aqueous extraction, and the effect of crosslinking agents on the durability and extent of polymerization were tested with a fluorescein spot and a bromophenol solution test. The results of these colorimetric analytical methods were in perfect agreement with those of antimicrobial tests, XPS, and SEM analysis. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 2397-2407, 2010