Optofluidic Device for Passive Sex Sorting of Sperms

A recently completed SUPA START project between Giltech and St Andrews University has explored the feasibility of sorting sperm into different sexes using an optofluidic device.
Optofluidic Device for Passive Sex Sorting of Sperms
Giltech and University of St Andrews
 
A recently completed SUPA START project between Giltech and St Andrews University has explored the feasibility of sorting sperm into different sexes using an optofluidic device.
 
Giltech, based in Ayr, specialises in creating biodegradable and controlled release technologies. These technologies are used in medical and healthcare products. The company had identified that the sex-sorting of mammalian sperm is an area of high interest for veterinary companies for regulating the sex of offspring at conception.
 
The Optical Manipulation Group in the University of St Andrews, works in a number of research areas of optics and biophysics, with a view to develop optical micromanipulation using light, optical traps in microfluidic environments and novel laser techniques for cell biology and medicine.
 
This project looked at the feasibility of implementing a passive optical sorting technique to achieve sex sorting of sperms so that external tagging could be avoided when compared to already established active sorting techniques.
 
The project aimed at combining an optical trapping system with a microfluidic platform to achieve passive sex sorting of sperm samples. The basic idea is to create an optical landscape in a microfluidic channel through which the sperm cells flow and due to the variation in the refractive index of sperms with X chromosome or Y chromosome, sperm samples with a particular chromosome would get selectively deflected into separate channels.
 
As part of the SUPA start project, a microfluidic chip was designed, which was combined with an optical trapping system, capable of generating time multiplexed optical traps using an Acousto Optic Deflector (AOD). Bovine sperm flowed through the microfluidic chip and the buffer medium was optimized so that sperm samples would experience maximum optical force from the optical trap. This was crucial to achieve selective deflection of sperm cells.
 
Further exploration would be necessary to find the optimum fluidic and optical parameters to achieve efficient optical deflection of sperm cells within a microfluidic flow, in order to ascertain the possibility and effectiveness of sex-based fractionation of sperm cells using passive optical sorting techniques.