Nozzle assembly for a flow cytometry system and methods of manufacture

1. A method of sorting cells comprising:

magnetically coupling a nozzle assembly to a stage of a flow cytometer in a predetermined orientation, wherein the orientation is guided by an alignment element on the nozzle assembly;

forming a fluid stream having a sheath fluid and a sample fluid;

orienting particles within the sample fluid of the fluid stream;

interrogating oriented particles within the fluid stream at an inspection zone;

producing signals representative of emitted or reflected electromagnetic radiation at the inspection zone;

analyzing the produced signals to classify the cells; and

sorting cells according to the classification of each cell.

2. The method of sorting cells as claimed in claim 1 , further comprising:

removing the nozzle assembly from a magnetic seat; and

placing a replacement nozzle assembly in the magnetic seat.

3. The method of sorting cells as claimed in claim 1 , wherein the step of magnetically coupling the nozzle assembly to the flow cytometer in a predetermined orientation further comprises:

aligning an alignment notch formed in the nozzle assembly with an alignment element formed on a seat of the flow cytometer; and

coupling the nozzle assembly to the seat.

4. The method as claimed in claim 1 , further comprising the step of cleaning the nozzle assembly.

5. The method as claimed in claim 4 , wherein the step of cleaning the nozzle assembly further comprises debubbling the nozzle assembly.

6. The method as claimed in claim 1 , wherein the step magnetically coupling the nozzle assembly to the stage of the flow cytometer in a predetermined orientation further comprises: aligning an orienting nozzle tip within the nozzle assembly.

7. The method as claimed in claim 1 , wherein the step of sorting cells according to the classification of each cell comprises separating a live X-chromosome bearing subpopulation of sperm cells from the remaining cells, or separating a live Y-chromosome bearing subpopulation of sperm cells from the remaining cells, or separating a live X-chromosome and live Y-chromosome bearing subpopulation of sperm cells.

8. The method of sorting cells as claimed in claim 1 , wherein the nozzle assembly further comprises:

a) a nozzle housing enclosing a nozzle cavity;

b) a sample inlet formed in the nozzle housing;

c) an injection tube having a sample outlet, the injection tube being mounted with the nozzle housing and extending along the nozzle cavity, wherein the injection tube comprises a flow path providing fluid communication between the sample inlet and the sample outlet;

d) one or more sheath inlets in fluid communication with the nozzle cavity; and

e) a nozzle exit orifice downstream of the sample outlet.

9. The method of sorting cells as claimed in claim 8 , wherein the injection tube has an outer diameter less than 2 mm.

10. The method of sorting cells as claimed in claim 8 , wherein the nozzle assembly injection tube further comprises a geometry for producing a ribbon core stream.

11. The method of sorting cells as claimed in claim 8 , wherein the flow path between the sample inlet and the sample outlet is located on a single flow axis.

12. The method of sorting cells as claimed in claim 11 , wherein the injection tube is formed from an extruded polymer.

13. The method of sorting cells as claimed in claim 12 , wherein the orienting nozzle tip comprises an internal geometry that begins as an elliptical cross section and which tapers down to a circular cross section along the single flow axis.

14. The method of sorting cells as claimed in claim 8 , wherein the nozzle cavity comprises an angle of taper greater than 15 degrees.