Geometrical guidance and trapping transition of human sperm cells

(Received 19 December 2013; revised manuscript received 6 February 2014; published 28 March 2014)The guidance of human sperm cells under confinement in quasi-2D microchambers is investigated usinga purely physical method to control their distribution. Transport property measurements and simulations areperformed with diluted sperm populations, for which effects of geometrical guidance and concentration arestudied in detail. In particular, a trapping transition at convex angular wall features is identified and analyzed.We also show that highly efficient microratchets can be fabricated by using curved asymmetric obstacles to takeadvantage of the spermatozoa specific swimming strategy.DOI: 10.1103/PhysRevE.89.032720 PACS number(s): 87