Plasma treatment of polystyrene (PS) culture dishes enhances cell adhesion

Cell culture is the most core and fundamental technology in biotechnology; A culture dish is a laboratory vessel used for culturing microorganisms or cells. Currently, disposable plastic culture dishes are widely used in many fields such as biology, medicine, and chemical engineering. Plastic products have become the preferred polymer materials for experimental analysis in industries such as biology and medicine due to their low price.

The current disposable plastic culture dishes, such as polystyrene (PS), have many advantages, such as high transparency, excellent rigidity, low cost, non toxicity, good resistance to solvents and electrical insulation, excellent surface glossiness, and good processability. However, when polystyrene is applied in fields such as biomedicine, due to its hydrophobic surface, it cannot fully meet the biocompatibility and high biological functional requirements required as a biomedical material, making it very difficult to use for adherent culture of bacteria and cells. Usually, surface treatment is required before use to improve the hydrophilicity, hydrophobicity, and biocompatibility of the material surface, in order to broaden the application range of polystyrene materials. The hydrophilicity and hydrophobicity of polystyrene surface can affect the adhesion and binding of polymers to molecules in contact with its surface.

To address these issues, low-temperature plasma surface modification technology has been widely applied in biomedical materials due to its unique advantages.

PS culture dish plasma treatment

Plasma contains a large number of high-energy particles, such as electrons, ions, free radicals, and some neutral substances. Although these active particles have a short lifespan, they are very active and can easily undergo chemical reactions with other substances in the system. Therefore, plasma can be used for surface treatment of materials. The energy of active particles in low-temperature cold plasma is sufficient to break the chemical bonds of molecules, but it does not cause the material surface to overheat, and is still applicable to some high-temperature unstable polymers. In addition, plasma treatment of material surfaces only affects depths of a few nanometers below the surface, without damaging the internal structure of the material or altering its optical properties. Secondly, plasma treatment does not produce toxic chemicals, making the plasma surface treatment process safe, reliable, non-toxic, and environmentally friendly.

Comparison of droplet angles before and after PS oxygen plasma treatment

Figure 1 Comparison of droplet angles before and after plasma treatment of polystyrene

From Figure 1, it can be seen that the contact angle of PS culture dishes without plasma treatment is very large. After plasma treatment, the droplet angle becomes very small, and the PS surface reaches a superhydrophilic state.

For polystyrene (PS), its chemical structure includes a benzene ring, which is usually not biocompatible due to its lack of natural expression in the human body. Oxygen plasma can effectively destroy these benzene rings and replace them with oxygen-containing groups such as hydroxyl and carbonyl groups (Figure 2).

Figure 2 Plasma oxidation of polystyrene

After plasma treatment, the surface energy of polystyrene (PS) culture dishes will increase, the surface morphology will become rough, and the chemical composition will also change. The surface will introduce oxygen-containing functional groups such as hydroxyl OH and carboxyl COOH, which can significantly improve the hydrophilicity and biocompatibility of the material, thereby increasing the adhesion of cells or proteins to the polymer surface.

Custom PS Substrates — Beyond Standard Culture Dishes

NAEN's desktop plasma cleaners support oxygen plasma activation of custom polystyrene substrates beyond standard culture dishes, enabling researchers to create specialized culture surfaces:

Polystyrene films and membranes — Thin PS films used as transparent substrates for live-cell imaging, microfluidic channel floors, or transwell-style membrane inserts can be plasma-treated to achieve cell-adhesive surfaces with optical quality maintained.

Microfluidic PS chips — PS is increasingly used for microfluidic organ-on-chip devices as a lower-cost alternative to PDMS. Oxygen plasma treatment activates PS channel surfaces for cell seeding, bonding of PS layers, and hydrophilic flow priming.

3D-printed PS scaffolds — Fused filament fabrication (FFF/FDM) 3D printing of PS produces scaffolds with natively hydrophobic surfaces. Plasma activation converts the printed scaffold surface to TCPS-equivalent chemistry, enabling 3D adherent culture directly on printed architectures.

Multi-well plates and custom formats — Standard or custom PS multi-well plates (6-well, 24-well, 96-well) can be plasma-treated in batch within the chamber volume of NAEN desktop plasma cleaners, activating all well surfaces simultaneously without individual handling.

Equipment Used — NAEN Desktop Plasma Cleaner for PS Culture Dish Treatment

For polystyrene culture dish plasma treatment in research and pilot-scale production, NAEN's desktop plasma cleaner series provides the required combination of RF plasma capability, process gas control, and chamber geometry:

• NAEN Desktop Plasma Cleaners — Compact 2–15L vacuum chamber units operating at 13.56 MHz, suitable for single-dish treatment and small multi-dish batches in research laboratory environments. Dual MFC gas channels support O₂, N₂, Ar, and mixed gas protocols for different cell type requirements.

For larger-scale production of custom TCPS-grade culture vessels, NAEN's industrial plasma cleaners provide the high-volume batch processing capacity and PLC-controlled process repeatability required for consistent surface quality across production batches.

For further information on plasma treatment in biomedical applications, see NAEN's biomedical application page.

Inquire Now for pricing, customization options, or to discuss your specific plasma cleaning or surface treatment requirements. Our team is ready to help select the right parameters and process gases for optimal results with other systems in our desktop plasma cleaner lineup.