High-Throughput Lensfree 3D Tracking of Human Sperms
SUMMARY
UCLA researchers have developed a lensfree technique to track three-dimensional trajectories of individual human sperms.
BACKGROUND
The singular purpose of a mammalian sperm cell is to deliver genetic material to the female gamete. Researchers in the past century have investigated the mechanics of sperm propulsion in order to better understand its characteristics. However, due to its small size and fast speed, the swimming path of sperm cells is often studied using two dimensional techniques, even though their physiological functions are performed in three-dimensional environments. Thus, there exists an unmet need to develop techniques to track and study the three-dimensional trajectories of sperm to gain a better understanding of their function within the body.
INNOVATION
Researches in the UCLA Department of Electrical Engineering have developed a lensfree on-chip imaging technique that can track the three-dimensional trajectories of >1,500 individual human sperms within an observation volume of approximately 8 – 17 mm3. The motion has submicron positioning accuracy, enabling researchers to reveal a number of interesting characteristics of sperm. This imaging platform may lead to new insights in the 3D motion and biophysical characteristics of human sperm cells. For example, highly notable characteristic discovered with this technique is that a large majority of sperm sampled preferred to swim in right-handed helices over left-handed ones.
APPLICATIONS
This method can be extremely valuable for the continuous observation of mammalian sperm cell swimming patterns in addition to physical properties of other microorganisms.
ADVANTAGES
The technology developed can track the 3D trajectories of human sperms across a large volume with high positioning accuracy.
STATE OF DEVELOPMENT
The technique has been developed and tested on human sperm cells.
RELATED MATERIALS
- Su et al., Sperm Trajectories Form Chiral Ribbons, Nature, 2013, 3, 1664
- Su et al., High-throughput lensfree 3D tracking of human sperms reveals rare statistics of helical trajectories. Proc. Natl. Acad. Sci., 2012, 109, 16018
- Su et al., Compact and Light-Weight Automated Semen Analysis Platform Using Lensfree on-Chip Microscopy, Anal. Chem., 2010, 82(19)