Scientists at Institute of Technology report research in life sciences.

New investigation results, 'Replica-moulded polydimethylsiloxane culture vessel lids attenuate osmotic drift in long-term cell cultures,' are detailed in a study published in Journal of Biosciences. "An imbalance in medium osmolarity is a determinant that affects cell culture longevity. Even in humidified incubators, evaporation of water leads to a gradual increase in osmolarity over time," scientists writing in the Journal of Biosciences report (see also Life Sciences).

"We present a simple replica-moulding strategy for producing self-sealing lids adaptable to standard, small-size cell-culture vessels. They are made of polydimethylsiloxane (PDMS), a flexible, transparent and biocompatible material, which is gas-permeable but largely impermeable to water. Keeping cell cultures in a humidified 5% CO[subscript]2 incubator at 37 degrees C, medium osmolarity increased by +6.86 mosmol/kg/day in standard 35 mm Petri dishes, while PDMS lids attenuated its rise by a factor of four to changes of +1.72 mosmol/kg/ day. Depending on the lid membrane thickness,pH drifts at ambient CO[subscript]2 levels were attenuated by a factor of 4 to 9. Comparative evaporation studies at temperatures below 60 degrees C yielded a 10-fold reduced water vapour flux ...