Plastic microfuge tubes
Plastic microfuge tubes

Chlorella cells stick to the sides of 1.5 ml plastic microfuge tubes during centrifugation.

Triton X-100, sarkosyl, serum albumin and polyvinylpyrrolidone prevent sticking, 0.5M LiCl or 10mM EGTA do not.

Triton X-100 levels down to 0.01% are effective (suggests surface effects)

Be aware of Bioactive Contaminants Leach from Disposable Laboratory Plasticware, McDonald, G.R. et al, Science 322, 917 (2008)

This paper notes that antistatics (cationic detergents) and slip agents (long chain fatty acid amides) are common plasticware additives. Chlorella binding is likely intrinsic to polypropylene but could be affected by additives.

The composition of so-called "non stick" plastics is difficult to track down, but apparently they're made from clarified polypropylene. Clarified polypropylene relies on additives (dibenzylidene sorbitol) to inhibit polypropylene crystallization and thus reduce light scattering by the plastic. Compostions of these plastics are proprietary.

Stability of the Lactose Permease in Detergent Solutions, Engel, C.K., Chen, L., and Prive, G.G., Biochim et Biophys Acta - Biomembranes - 1564, 47-56 (2002) - describes materials which leach out of various plastics, including clarified polypropylene.