July 18, 2025
How to remove Biofilm? Current Biofilm Removal Methods and Their Limitations
A Critical Look at Physical, Chemical, and Emerging Approaches
Computer Render of ultrafine bubbles piercing through the EPS matrix of biofilm.
Biofilms—complex, surface-attached microbial communities—present persistent challenges across industries, from healthcare and food processing to agriculture and water systems. Once established, biofilms become highly resistant to antibiotics, disinfectants, and physical removal, making them difficult to eliminate completely. Understanding the current methods used to control biofilms—and their limitations—is essential for designing effective, sustainable interventions.
What Makes Biofilms So Difficult to Remove?
Unlike free-floating (planktonic) bacteria, biofilms are embedded in a self-produced matrix of extracellular polymeric substances (EPS). This matrix:
— Acts as a physical barrier against cleaning agents
— Allows nutrient trapping and waste removal
— Facilitates cell-to-cell communication and genetic exchange
— Enables adaptive resistance to antimicrobial stress
This structural and functional complexity makes biofilms 100–1,000 times more resistant to biocides than planktonic microbes.
Chemical Treatments
1. Chlorination and Hydrogen Peroxide
Usage: Common in water systems, food processing, healthcare.
Mechanism: Oxidize cell membranes and denature proteins.
Limitations:
Incomplete penetration through EPS
Promotes resistance and regrowth if sublethal
Forms disinfection byproducts (DBPs) harmful to health and environment
Corrosive to pipes and equipment
2. Acid/Base Treatments
Usage: Common in water systems, food processing, healthcare.
Usage: Flushing irrigation systems, industrial pipelines.
Mechanism: Disrupt microbial cells and dissolve biofilm matrices.
Limitations:
Requires careful pH control
May damage host materials (plastics, metals)
Not selective—can kill beneficial microbes
3. Enzymatic Cleaners
Usage: Medical devices, food surfaces.
Mechanism: Break down EPS components like polysaccharides, proteins, and DNA.
Limitations:
High cost
Sensitive to temperature and water chemistry
Limited long-term effectiveness
Physical Removal Methods
1. High-Pressure Flushing / Scrubbing
Usage: Pipelines, tanks, industrial machinery.
Mechanism: Dislodges biofilm mechanically.
Limitations:
Biofilms rapidly regrow on scratched or roughened surfaces
Incomplete removal, especially in corners, crevices
Not suitable for sensitive equipment
2. Ultrafine bubbles (Nanobubbles)
Usage: Pipelines, tanks, industrial machinery.
Generate reactive oxygen species and disrupt adhesion
Limitations:
No current limitation found
Key Challenges Across All Methods
EPS Barrier: Protects inner cells from treatment.
Dormant Cells: “Persister” cells can survive harsh conditions and repopulate.
Regrowth: Unless completely removed, biofilms can reform quickly—sometimes more resistant than before.
System Design: Complex geometries (e.g., dead zones in pipes) prevent uniform treatment.
Environmental Impact: Overuse of chemicals harms surrounding ecosystems and fosters resistant strains.
Bottom Line
Biofilm control remains a multifactorial challenge. While existing physical and chemical methods offer partial solutions, they often fail to achieve total eradication—and may introduce new complications like corrosion, resistance, or environmental harm. A combination of preventive design, regular monitoring, and next-generation technologies (e.g., nanobubbles, enzymes, surface coatings) will be critical in addressing the persistent threat of biofilms.
FAQ
Why Don’t Traditional Disinfectants Work Well on Biofilms?
Because biofilms are encased in a protective EPS matrix that limits chemical penetration and supports microbial resistance.
Can You Ever Fully Remove a Biofilm?
Do Biofilms Always Come Back After Cleaning?
Are There Environmentally Friendly Biofilm Removal Methods?
Is Biofilm Resistance the Same as Antibiotic Resistance?
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