Microfabricated two-pin liquid sample dispensing system

• US 20060027524A1
• Filed: 09/30/2005
• Published: 02/09/2006
• Est. Priority Date: 09/25/2001
• Status: Abandoned Application

• Current Assignee: Cytonome Inc.
• Original Assignee: Cytonome Inc.
• Inventors: Gilbert, John, Harley, John
• Application Number:
  US11/240,715
• Publication Number:
  US 20060027524A1
• Time in Patent Office: Days
• US Class Current: 216/2
• CPC Class Codes: B01L 2200/143 Quality control, feedback systems
• CPC Class Codes: B01L 2200/147 Employing temperature sensors
• CPC Class Codes: B01L 2400/0439 ultrasonic vibrations, vibrating piezo elements
• CPC Class Codes: B01L 3/0244 using pins
• CPC Class Codes: B01L 3/0248 Prongs, quill pen type dispenser
• CPC Class Codes: G01N 2035/1037 Using surface tension, e.g. pins or wires
• CPC Class Codes: Y10T 436/119163 with aspirator of claimed structure
• CPC Class Codes: Y10T 436/25625 Dilution
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A two-pin liquid sample dispensing system is provided. The two-pin dispensing system comprises a pair of separately movable pins for holding a droplet of liquid therebetween. Each pin includes a tip spaced predetermined distance from the other pin to define a sample acquisition region. The pins acquire and hold a droplet of the liquid sample in the sample acquisition region formed in the space between the tips and apply the droplet to a selected sample handing system. The distance between the tips is variable to accommodate different liquid samples having varying physical properties and to vary the volume of the acquired droplet.

Claims

1. A method of fabricating a liquid sample dispensing system, comprising:

providing a substrate;

applying a pattern to the substrate to define a holder, a first pin having a first tip and a second pin having a second tip spaced from the first tip to define a sample acquisition region; and

etching the substrate to remove excess portions of the substrate, thereby fabricating the liquid sample dispensing system.

2. The method of claim 1, wherein the substrate comprises a silicon wafer.

3. The method of claim 1, wherein the substrate comprises a glass plate.

4. The method of claim 1, further comprising the step of applying a chemical coating to at least one of the first pin and the second pin.

5. The method of claim 1, wherein the first and second pins are movable relative to each other.

6. The method of claim 1, further comprising the step of coupling an actuator to the etched substrate for varying a separation distance between the first tip and the second tip.

7. The method of claim 1, further comprising the step of coupling a sensor to the etched substrate for sensing the separation distance between the first tip and the second tip.

8. The method of claim 1, further comprising the step of coupling a sensor to the etched substrate for measuring the physical properties of a liquid sample held in the sample acquisition region.

9. The method of claim 8, further comprising the step of coupling an actuator to the etched substrate, wherein the actuator varies the separation distance in response to the measurement of the physical properties.

10. The method of claim 1, wherein the pattern includes a driver for moving the first pin relative to the second pin.

11. The method of claim 1, wherein the first pin and the second pin have a length of about five millimeters.

12. The method of claim 1, wherein the sample acquisition region has a volume between about 6.25 nanoliters and about 31.5 nanoliters.

13. The method of claim 1, wherein an array of liquid sample dispensing systems is formed on a single substrate.

15. The method of claim 1, wherein the silicon wafer has dimensions of about one square centimeter.

16. The method of claim 1, wherein an array of liquid sample dispensing systems is formed on a single silicon wafer.

14. A method of microfabricating a liquid sample dispensing system, comprising the steps of:

providing a silicon wafer;

applying a pattern to the silicon wafer to define a holder, a first pin having a first tip and a second pin having a second tip spaced from the first tip to define a sample acquisition region; and

etching the silicon wafer to remove excess portions of the substrate, thereby fabricating the liquid sample dispensing system.

17. A method of fabricating a liquid sample dispensing system, comprising:

providing a substrate;

applying a pattern to the substrate to define a holder and a first pin having a first tip defining a sample acquisition region;

etching the substrate to remove excess portions of the substrate, thereby fabricating the liquid sample dispensing system; and

applying a chemical coating to the first pin.

18. The method of claim 17, wherein the chemical coating comprises one of a hydrophobic material and a hydrophilic material.

19. The method of claim 17, wherein the chemical coating is applied in a predetermined pattern determined by a mask used in applying the chemical coating to the tip.

20. The method of claim 17, wherein pattern also defines a second tip that is etched in the substrate spaced from the first tip to define the sample acquisition region.