Color measurement as a means of quantifying surface biofouling

Area of Science:

• Microbiology
• Biotechnology
• Materials Science

Background:

• Biofilm formation is a significant challenge in various industrial and medical settings.
• Accurate and non-destructive methods for monitoring biofilm accumulation are essential for effective control strategies.

Purpose of the Study:

• To develop and validate a rapid, non-destructive colorimetric assay for quantifying biofilm accumulation.
• To establish the correlation between color change and viable cell density in biofilms.

Main Methods:

• Laboratory reactors with ceramic porcelain surfaces were inoculated with environmental biofilm-forming isolates.
• A Minolta colorimeter CR-200 and a custom adapter were used to measure the reflective color of fouled surfaces.
• Areal viable cell counts were monitored over eleven days, alongside direct color measurements.

Main Results:

• A strong linear relationship was observed between log cell density and log color change (r = 0.95).
• The colorimetric assay was found to be non-destructive and immediate.
• Partial correlation analysis confirmed that the relationship between cell density and color change was independent of time (r = 0.87).

Conclusions:

• Reflective color measurement offers a rapid, non-destructive, and quantitative method for assessing biofilm accumulation.
• This colorimetric approach provides a reliable alternative to traditional cell counting methods for monitoring biofilm development.