Experimental Study of Sperm Separation for In Vitro Fertilization Applications Using Inherent Instincts of TheFluid and Sperms Motility

Background: Nowadays, applications and performance of microfluidicchips in medicine and engineering is outstanding. Incases such as cancer, there have been many achievements indiagnosis, treatment, purification and drug delivery, by usingvariable procedures on a microfluidic chip. In this research, thesemen sample would be purified from other debris and the finalsample would be manipulated in order to auto select the highquality sperms. The unique design of this microchip is basedon the inertial-force-induced separation. The flow Reynoldsnumber is the ratio of inertial forces to viscous forces. Anotherdimensionless number is particle Reynolds number; criteria thatstates the dominance of rather inertial or viscus forces, that canbe expressed by the size ratio of the particles to the channellength scales(a/D_h).Materials and Methods: The first section of this deviceis the inertial separation section, which allows the smallerparticles(sperms) to move along the streamlines, while the otherparticles(WBCs) move straight forward due to their higherdiameter and density. As the smaller particles are going throughthe side channels, there are some microarrays in order to filterthe sample from probable debris or impurities. In this section,the purity of the final sample will be guaranteed by usingmicro-pillars. In the last section of the chip, as the velocity ofthe flow will decrease dramatically, there are two side channelswith divergence angle of ۴۵ºin order to capture the left or rightswimmersperms. As it has been addressed in recent researches,sperms with the ability to swim to the left or right, are capableof having higher HDS (High DNA Stainability) and also lessDFI (DNA Fragmentation Index).Results: By using a combination of hydrodynamic techniqueand microarrays, a new method of sperm purification has beenevaluated which is label free and also leads us to a non-intrusiveand non-invasive separation procedure. This microchipprovides a very faster process through sperm purification, alsobenefits a pre-collection of high quality sperms for in vitro fertilization(IVF) procedure.Conclusion: In this research we designed a microchip whichis able to purify the semen sample from other debris, also autoselect the high quality sperms for being used in the IVF procedure.This microchip would be a suitable filed for other sections(magnetic field) in order to do the sex-selection as well. Also,this microchip could be commercialized as a home use devicein order to do a pre-assessment on semen sample at home forfurther information about the quality of the semen sample.

کلیدواژه ها:

Microchip ، Sperm Separation ، Motility ، Inertial Forces ، High Quality Sperms