Biofilm extracellular polymeric substances can act as a barrier to antifungal agents reaching the target site of yeast cells
in the basal layer which results in resistance to various antifungal drugs. The aim of this study was to use a Franz diffusion
apparatus to investigate the penetration of cinnamon oil and chlorhexidine (CHX) in various combinations through a Candida
albicans biofilm. This study demonstrated that 0.5% (w/v) CHX and in combination with cinnamon oil solution (8 L/mL)
penetrated the C. albicans biofilm. In addition, sessile C. albicans biofilms exposed to 0.5% (w/w) CHX and in combination with
cinnamon oil (8 L/mL) for 4 h resulted in log reductions. In conclusion, this in vitro method may be used to investigate the
penetration of antimicrobial solutions through C. albicans biofilm qualitatively and quantitatively at timed intervals.