Comparison of microporous membrane morphologies using confocal scanning laser microscopy

Confocal scanning laser microscopy (CSLM) was investigated for the characterization of microfiltration membrane morphology. Three microfilration membranes were studied: a closed-cellular morphology (cellulose acetate membrane, Sartorius), a ‘lacy’-like morphology (poly(vinylidene fluoride), Durapore, Millipore) and a cylindrical pores membrane (polycarbonate, Isopore, Millipore). Prior to visualization, the microporous membranes were mounted in immersion oil. Optical sections were taken at 1 μm intervals. All membranes were observed on 10 μm thickness from their surface, on both sides. CSLM was found useful to characterize microporous membrane morphologies and was compared to scanning electron microscopy (SEM) which views only surfaces.