Kill event optimization

Patent metadata

Field	Value
Publication number	US-11513114-B2
Application number	US-202015929938-A
Country	US
Kind code	B2
Filing date	May 29, 2020
Priority date	May 29, 2019
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

A method of choosing which undesired cell to destroy in a multi-cell fluorescent event includes detecting fluorescence of cells, converting photons detected in the fluorescence into an analog voltage output signal, and identifying at least two discernable peaks associated with the cells. By looking solely at properties measured within the multi-cell fluorescent event, a decision of which cell to target for elimination can be made. Using this method with large population sizes can result in an effective sex skewed product. The sex skewed product can, for example, be formed from bull semen which is then later used to inseminate cows which results in an increased likelihood of giving birth to female cattle.

First claim

What is claimed is:

1. A method to discriminate an undesired cell in a multi-cell fluorescent event comprising:
detecting a fluorescence of at least two cells physically spaced close enough such that the at least two cells create one fluorescent event;
classifying each cell as an undesired cell or a desired cell based on the detection of the fluorescence of the at least two cells;
allowing each desired cell to pass; and
acting on each undesired cell.

2. The method of claim 1 , wherein said acting on each undesired cell involves mechanical sorting, fluid switching, acoustic-assisted hydrodynamic focusing, photonic pressure, electrolysis or electroporation, or laser ablation.

3. The method of claim 1 further comprising firing a kill beam with the kill laser to destroy each undesired cell.

4. The method of claim 1 further comprising creating a sample flow by allowing a sheath fluid to enter a semen sexing instrument.

5. A sexed semen product formed as the result of executing the method of any one of claims 1 , 2 , 3 or 4 .

6. The method of claim 1 further comprising introducing cell dye into the at least two cells.

7. The method of claim 1 further comprising exciting the at least two cells with a detection laser or a light emitting diode to cause the fluorescence.

8. The method of claim 1 further comprising collecting each desired cell.

9. The method of claim 1 wherein the fluorescence of the cell determines the sex of the at least two cells.

10. The method of claim 1 further comprising measuring a purity percentage associated with a population of cells.

11. A method of selecting which undesired cell to destroy in a multi-cell fluorescent event comprising:
detecting a fluorescence of at least two cells physically spaced close enough such that the at least two cells create one fluorescent event;
converting photons detected in the fluorescence of the at least two cells into an analog voltage output signal;
identifying a first peak in the analog voltage output signal and associating the first peak with a first cell;
identifying a second peak in the analog voltage output signal and associating the second peak with a second cell;
measuring an amplitude of the first peak and an amplitude of the second peak; and
defaulting a kill laser to fire a kill beam at any cells having an amplitude less than an amplitude of another cell.

12. The method of claim 11 further comprising:
defining a dead cell threshold percentage or an adjustable fixed value;
determining the difference between the amplitude of the first peak and the amplitude of the second peak;
determining if the difference between the amplitude of the first peak and the amplitude of the second peak is greater than the dead cell threshold percentage or the adjustable fixed value; and
configuring the kill laser to override the defaulting step and to fire at any cells having an amplitude higher than an amplitude of another cell if the difference is greater than the dead cell threshold percentage or the adjustable fixed value.

13. The method of claim 11 further comprising filtering and digitizing the analog voltage output signal.

14. A sexed semen product formed as the result of executing the method of any one of claims 11 , 12 or 13 .

15. A sexed semen system comprising:
a source of sperm cells;
a detection laser capable of exciting a sperm cell;
a fluorescence detector;
a computer processing unit for determining the sex of the sperm cell based on an output of the fluorescence detector;
an analog to digital converter (ADC) which converts an analog voltage output signal from the fluorescence detector into a digital output signal;
a field programmable gate array (FPGA) receiving the digital output, the FPGA having an ADC state tracker machine which monitors a raw ADC value of the analog voltage output signal to determine if a multi-cell fluorescent event has occurred, and if so, to classify each sperm cell as desirable or undesirable; and
a kill laser for destroying an undesirable sperm cell.

16. The system of claim 15 wherein the source of sperm cells comprises a sheath fluid encapsulating the sperm cells.

17. The system of claim 15 wherein the fluorescence detector is an avalanche photodiode (APD) sensor.

18. The system of claim 15 wherein the ADC tracker state machine includes an IDLE state, a RISING state, a PEAK state, a FALLING state, and a VALLEY state.

19. The system of claim 15 further comprising a general purpose processor (GPP) or a digital signal processor (DSP) using a defined gate to generate a fire signal to the FPGA with the option of the FPGA to make a kill decision based on the defined gate.

20. The system of claim 15 further comprising a low pass filter for passing signals with a frequency lower than a selected cutoff frequency.

Assignees

• Abs Global Inc

Inventors

• Savage Frederick
• Ebersole Matthew
• Mcada Daniel
• Appleyard David
• Xia Zheng

Classifications

• G01N33/533

  with fluorescent label · CPC title

• G01N2015/1006

  for cytology · CPC title

• G01N33/5091 Primary

  for testing the pathological state of an organism · CPC title

• G01N15/1459

  the analysis being performed on a sample stream · CPC title

• G01N21/6486

  Measuring fluorescence of biological material, e.g. DNA, RNA, cells (G01N21/6428 takes precedence) · CPC title