Method and Apparatus for Gender Selection Based on PH

Abstract

The present invention includes methods and apparatus to separate X or Y-chromosome bearing sperm cells in a population by first placing the population of sperm cells at physiological pH environment, and simultaneously contacting the population of sperm cells with one or more additional sub-environments with different pH values. The exposure allows mobile sperm cells bearing X or Y-chromosome to migrate to the different pH sub-environments, wherein each cell only exposed or come in contact with one pH sub-environment. Finally, the collecting X or Y-chromosome enriched population of sperm cells is performed.

What is claimed is: 
     
         1 . An apparatus for increasing the proportion of X or Y-chromosome bearing sperm cells in a population comprising:
 one or more containers, wherein the container comprises at least one main chamber; and   two or more sub-chambers adjacent the main chamber, wherein the main chamber and sub-chambers are separated by a biocompatible mesh material, wherein the vessels are adapted to receive fluids comprising two or more separate pHs and the openings in the mesh permit the passage of sperm.   
     
     
         2 . The apparatus of  claim 1 , wherein the biocompatible mesh material comprise openings of about 40-70 μm. 
     
     
         3 . The apparatus of  claim 1 , wherein the biocompatible mesh material permits sufficient minor exchange of ions 
     
     
         4 . The apparatus of  claim 1 , wherein the sufficient minor exchange is significant to permit mobility pathways for sperm cells. 
     
     
         5 . The apparatus of  claim 1 , wherein the biocompatible mesh material prevent mass flow of fluid between the chambers, but allows free movement of sperm cells and slow movement of fluids between chambers. 
     
     
         6 . The apparatus of  claim 1 , wherein the pH of the chambers includes two or more pHs selected from 5, 6, 7, 7.5, 7.8, 8, 8.5, 9 and 9.5. 
     
     
         7 . The apparatus of  claim 1 , wherein the biocompatible mesh vessel comprises an electrostatic charge, static pressure, or both that prevent movement of the solutions through the mesh. 
     
     
         8 . The apparatus of  claim 1 , wherein the physiological pH environment, the additional environments or both comprise a thixotropic agent. 
     
     
         9 . The apparatus of  claim 1 , wherein the biocompatible mesh vessel openings are customized to the size of the sperm sorted. 
     
     
         10 . The apparatus of  claim 1 , further comprising the step of collecting the X or Y-chromosome enriched population of sperm cells from one or both sides of the interface between the physiological pH and the adjacent chambers.