ASTM E2196-23 PDF

Overview

ASTM E2196-23 is the international standard test method issued by ASTM International for the quantification of Pseudomonas aeruginosa biofilm grown under medium shear and continuous flow conditions using a rotating disk reactor. This standard guides laboratories in cultivating reproducible biofilms, particularly for assessing population density, viability, and characteristics on solid surfaces under controlled, laboratory-simulated environments. Originally developed to mimic biofilm conditions found in toilet bowls, the method is adaptable to a range of biofilm species and growth conditions, making it highly relevant for research on microbial resistance, antimicrobial efficacy, and surface disinfection.

Key Topics

• Biofilm Formation and Analysis

  • Focuses on understanding bacterial phenotype changes in biofilms compared to suspended cells
  • Outlines procedures to grow and analyze Pseudomonas aeruginosa biofilms using controlled shear and nutrient flow

• Rotating Disk Reactor (RDR) Methodology

  • Utilizes a continuously stirred tank reactor (CSTR) with rotating disk and coupons as the biofilm sampling surface
  • Establishes steady-state biofilm conditions conducive to relevant laboratory studies

• Quantification of Viable Cells

  • Details sampling and enumeration techniques, including scraping, homogenization, serial dilution, and plating
  • Population density is computed as log10 colony forming units (CFU) per surface area

• Reproducibility and Laboratory Best Practices

  • Recommends randomization to minimize bias in biofilm studies
  • Emphasizes proper sterilization, culture preparation, and safety protocols

Applications

ASTM E2196-23 is valuable for laboratories, research institutions, and product development sectors focused on biofilm research, antimicrobial testing, and disinfectant efficacy. Its applications include:

• Simulating Real-World Biofilm Environments

  • Mimics conditions found in toilets and similar settings
  • Enables realistic studies on detachment, growth rates, and microbial resistance in biofilms under medium fluid shear

• Antimicrobial Agent Testing

  • Helps evaluate the effectiveness of antibiotics and disinfectants by providing a reproducible method for biofilm formation and viability analysis

• Material and Surface Studies

  • Assesses how different materials (e.g., polycarbonate, stainless steel, glass) influence biofilm development and resilience

• Water and Wastewater Research

  • Suitable for bacteriological assessments in environmental and public health laboratories where biofilm control is essential

• Fundamental Microbiology Training

  • Serves as a hands-on protocol for training staff in microbiological sampling, laboratory best practices, and analytical accuracy

Related Standards

For comprehensive and consistent biofilm research, ASTM E2196-23 references several related standards, including:

• ASTM E2756

  • Terminology Relating to Antimicrobial and Antiviral Agents

• ASTM D5465

  • Practices for Determining Microbial Colony Counts from Waters Analyzed by Plating Methods

• Standard Methods for the Examination of Water and Wastewater

  • Reference for sample preparation and microbial dilution water (Method 9050 C.1.a)

Adopting ASTM E2196-23, in conjunction with related standards, ensures that laboratory research on biofilms is scientifically rigorous, industry-comparable, and aligned with international best practices for microbial testing and antimicrobial efficacy studies.

Keywords: Pseudomonas aeruginosa, biofilm quantification, rotating disk reactor, medium shear, continuous flow, ASTM E2196-23, antimicrobial effectiveness, laboratory biofilm testing, colony forming units, microbiological analysis.