Method and apparatus for sorting X-chromosome bearing and Y-chromosome bearing populations of spermatozoa and particle differentiation

摘要

An apparatus for differentiating asymmetric particles with particular application to providing high purity X-chromosome and Y-chromosome bearing populations of spermatozoa is described. The apparatus includes an irradiation source 12, such as a laser exciter, that produces a beam 31 that is focused to have a beam height of between one and three times the length of the asymmetric particles. A light emission material that emits light in response to the beam 31 is bound to the particles, and there is a detector 32 that responds to the emitted light. In the case of separating sperm cells fluorochrome is bound to the cell DNA. The selection of the beam height gives improved differentiation over previous separation devices where multiple sperm cell heads containing fluorochrome bound DNA can enter the irradiation beam pattern at the same time.