Standardized method for in vitro antifungal susceptibility testing of Candida albicans biofilms
- Antimicrob Agents Chemother. 2001 Sep;45(9):2475-9. doi: 10.1128/AAC.45.9.2475-2479.2001.
- 1. Department of Microbiology, Division of Infectious Diseases, The University of Texas Health Science Center at San Antonio, Texas 78245, USA.
Candida albicans is implicated in many biomaterial-related infections. Typically, these infections are associated with biofilm formation. Cells in biofilms display phenotypic traits that are dramatically different from those of their free-floating planktonic counterparts and are notoriously resistant to antimicrobial agents. Consequently, biofilm-related infections are inherently difficult to treat and to fully eradicate with normal treatment regimens. Here, we report a rapid and highly reproducible microtiter-based colorimetric assay for the susceptibility testing of Fungal biofilms, based on the measurement of metabolic activities of the sessile cells by using a formazan salt reduction assay. The assay was used for in vitro Antifungal susceptibility testing of several C. albicans strains grown as biofilms against amphotericin B and fluconazole and the increased resistance of C. albicans biofilms against these Antifungal agents was demonstrated. Because of its simplicity, compatibility with a widely available 96-well microplate platform, high throughput, and automation potential, we believe this assay represents a promising tool for the standardization of in vitro Antifungal susceptibility testing of Fungal biofilms.