In a petri dish, sperms become sluggish. Indeed, "poor sperm performance" is a common problem in IVF or in vitro fertilization.
Turns out, the polystyrene in the petri dish is toxic to the sperms - so what we do to help the sperms? Enter diamond:
Coat a quartz petri dish with a nanolayer of diamond, however, and you've created a cellular safe haven. A much higher percentage of sperm survived for 42 hours in diamond-coated petri dishes like the ones pictured above than in the polystyrene containers usually used for IVF, researchers will report in the Online Proceedings Library of the Materials Research Society.