ABSTRACT
Bi o f i l m s are ubiquitous and occur wherever sufficient water, inorganic and organic substrates can be found. They form at interfaces and represent the sessile form of life for microorganisms compared with the planktonic stage. Despite the growing recognition that biofilms represent the predominant form of life for microorganisms, few attempts have been made to investigate biofilms noninvasively and quantitatively. With the advent of confocal laser scanning microscopy (CLSM) and its introduction to medical and finally environmen tal sciences, it has become possible to look at biological structures without having to prepare samples for analysis. This has been an improvement over electron microscopy, which has been associated with introducing artifacts. Un til now, most microscopic studies of biofilms have been descriptive without attempting to derive quantitative information from the acquired images as re viewed by Caldwell et al. (1992a, 1992b). In some cases a small number of selected images were subjected to data analysis (Lawrence et al., 1989; Lawrence et al., 1991; Caldwell et al., 1992a, 1992b; Bloem et al., 1992). Here we present a method for routine measurements of biofilms using automated image acquisition and image analysis (Kuehn et al., 1998).
