Related Experiment Video
Updated: Jul 3, 2026
10:40
Fabricating and Labeling Microbubbles with Fluorescent and Radioactive Tracers
Published on: January 24, 2025
The protective effect of specific medium additives with respect to bubble rupture
D Chattopadhyay1, J F Rathman, J J Chalmers
1Department of Chemical Engineering, The Ohio State University, 140 W 19th Avenue, Columbus, Ohio 43210, USA.
Biotechnology and Bioengineering
|March 20, 1995
Summary
Protective agents in cell culture reduce cell damage by preventing cells from adhering to air bubbles. Additives that lower interfacial tension are most effective in protecting cells during suspension culture.
Area of Science:
- Biotechnology
- Cell Biology
- Chemical Engineering
Background:
- Suspension cell culture with air sparging causes significant cell damage.
- Cell damage is primarily attributed to cell-bubble interactions and adhesion to air-medium interfaces.
- Protective agents can mitigate this damage by preventing cell adhesion.
Purpose of the Study:
- To investigate the relationship between interfacial tension and the effectiveness of protective additives in preventing cell adhesion.
- To evaluate the protective characteristics of five different additives: Pluronic F-68, Methocels, dextran, Polyvinyl alcohol, and polyethylene glycols.
- To understand how additives impact cell damage during air-sparged suspension culture.
Main Methods:
- Measured liquid-vapor interfacial tensions of culture media with and without additives using the maximum bubble pressure and Wilhelmy plate methods.
- Employed visualization techniques to observe cell-bubble interactions and adhesion.
- Quantified cell death related to bubble rupture.
Main Results:
- Additives that rapidly decrease the liquid-vapor interfacial tension of the culture medium effectively prevent cell adhesion to bubble surfaces.
- Certain protective additives were shown to inhibit cell adhesion to bubbles.
- The extent of cell death due to bubble rupture correlated with the amount of cells adhering to the bubble surface.
Conclusions:
- Lowering interfacial tension is a key mechanism by which protective additives prevent cell damage in air-sparged cultures.
- The choice of additive significantly impacts cell protection by modifying interfacial properties.
- Interfacial tension modification offers a viable strategy for improving cell viability in suspension culture systems.
Related Concept Videos
01:13Excess Pressure Inside a Drop and a Bubble
The shape of a small drop of liquid can be considered spherical, neglecting the effect of gravity. This drop can further be considered as two equal hemispherical drops put together due to surface tension. The forces acting on the spherical drop are due to the pressure of the liquid inside the drop, the pressure due to air outside the drop, and the force due to the surface tension acting on the two hemispherical drops.
01:30Designing Growth Media for Bioreactors
Growth media provide essential nutrients that support cell growth and metabolism, thereby enhancing the yield of valuable products such as enzymes, antibiotics, and biomass. Designing an effective growth medium involves balancing all components to prevent nutrient limitations or toxic excesses, both of which can impair growth and reduce product yields.Composition of a Typical Growth MediumA typical growth medium contains carbon and nitrogen sources, salts, vitamins, trace elements, and...
01:18Bioreactor Controls-II
In aerobic fermentations, oxygen is vital for microbial growth and metabolite production. Since air comprises only about 20% oxygen and the gas is poorly soluble in water—just 9 ppm at 20°C—supplying sufficient oxygen becomes a critical challenge, especially in high-demand processes like yeast growth or citric acid production. Even a fully saturated broth may offer only a few seconds of oxygen availability.To address this, sterile or scrubbed air is introduced into the fermentor via a sparger...
01:27Microbial Growth Media
Microbial growth media are essential tools in microbiology, providing the nutrients and conditions necessary to cultivate and study microorganisms. These media are categorized by their composition, consistency, and functional roles, enabling researchers to investigate microbial physiology, behavior, and interactions.Types and Consistencies of Growth MediaGrowth media can be solid, liquid, or semisolid. Solid media, often agar-based, allow visible colony growth for isolation and enumeration.
01:28Methods of Medium Optimization
Optimizing growth media enhances microbial proliferation and maximizes product yield. Statistical experimental design methodologies provide structured and reproducible approaches, offering progressively higher levels of robustness and efficiency.The One-Factor-at-a-Time (OFAT) MethodThe One-Factor-at-a-Time (OFAT) method involves adjusting a single variable while keeping all others constant. However, it cannot detect interactions between variables, often leading to suboptimal outcomes when...
01:28Antimicrobial Effectiveness
The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...