Abstract

In this work microchannels fabricated with different biocompatible polymers were utilized to determine the adhesion rate with Escherichia coli suspension. Different polymeric surfaces – namely: cellulose acetate, polydimethylsiloxane, polystyrene, polyamide, poly L-Lactide and polyethylene oxide – were fabricated and implemented into the microchannel through the developed in-house method along with the xurographic technique. The method used to fabricate transparent microchannel is a modification of the existing polydimethylsiloxane soft lithography method. The molds are produced by xurography, simplifying the fabrication in laboratories without sophisticated equipment for photolithography. The adhesion rate for all polymeric surfaces were compared for two different wall shear stresses namely 0.01 Pa and 0.02 Pa. Attempts were made to relate biofouling rate with wall shear stress, hydrophobicity and zeta potential. Adhesion rate was small for very low shear stress and attained a maximum for 0.2 Pa. Also adhesion rate obtained were compared with the macroscale study with parallel plate flow chamber. There was not a statistical significant difference between adhesion at different scales for the same wall shear stress. The observed similarity between the adhesion rates is an added advantage, as it allows the choice of the scale experiment depending on the expertise and equipment available on the lab.