Plastic microchip for microparticle analysis and method for manufacturing the same

• US 20070238164A1
• Filed: 04/05/2007
• Published: 10/11/2007
• Est. Priority Date: 04/10/2006
• Status: Abandoned Application

• Current Assignee: Incyto Co., Ltd.
• Original Assignee: SKC Company Limited
• Inventors: Kim, Hyun Jin
• Application Number:
  US11/732,979
• Publication Number:
  US 20070238164A1
• Time in Patent Office: Days
• US Class Current: 435/287.200
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: B81B 2201/058 Microfluidics not provided for in B81B2201/051 - B81B2201/054
• CPC Class Codes: B81C 1/00119 Arrangement of basic structures like cavities or channels, e.g. suitable for microfluidic systems
• CPC Class Codes: B81C 2201/019 Bonding or gluing multiple substrate layers
• CPC Class Codes: B81C 2201/036 Hot embossing
• CPC Class Codes: G01N 15/1433 using image recognition
• CPC Class Codes: G01N 15/1459 the analysis being performed on a sample stream
• CPC Class Codes: G01N 15/1484 microstructural devices
• CPC Class Codes: G01N 2015/1486 Counting the particles

Abstract

Disclosed herein is a plastic microchip used in counting the number of microparticles and a method for manufacturing the same and, more particularly, to a plastic microchip including a negative microgrid pattern formed on a lower substrate, a solvent channel and solvent inlets for a solvent welding process, and a method for manufacturing the plastic microchip by injection molding the lower substrate on which a negative microgrid pattern is formed and by injecting a solvent through the solvent inlets so as to fix an upper substrate to the lower substrate.

According to the present invention, it is possible to form a microgrid pattern of a relatively narrow width deeply and uniformly as a negative microgrid pattern is formed on the lower substrate and thereby to provide a clear microgrid pattern, thus facilitating accurate observation of microparticles. Moreover, it is also possible to provide a uniform height of an injection chamber by welding an upper substrate and a lower substrate to each other by a solvent welding process, thus ensuring a more accurate analysis result.

Claims

1. A plastic microchip for microparticle analysis comprising light transmissive upper and lower substrates stacked up and down, an injection chamber defined between the upper and lower substrates, a sample inlet connected to one side of the injection chamber, an outlet connected to the other side of the injection chamber, and a microgrid pattern formed on the top surface of the lower substrate, for counting the number of microparticles in a sample contained in the injection chamber,

wherein the microgrid pattern on the top surface of the lower substrate is formed in a negative structure in which microlines of a groove shape are arranged in the form of a lattice on the top surface of the lower substrate.

2. The plastic microchip for microparticle analysis as recited in claim 1,

wherein a groove structure is formed adjacent to a wall established along the whole circumference of the injection chamber on the bottom surface of the upper substrate, and the groove structure and the top surface of the lower substrate forming a solvent channel along a predetermined path of the circumference of the injection chamber, and

wherein a plurality of solvent inlets is formed penetrating the top surface of the solvent channel to be opened at regular intervals along the solvent channel on the upper substrate.

3. The plastic microchip for microparticle analysis as recited in claim 2,

wherein the width of the solvent inlets is made more than 1 mm and the height thereof is more than 0.2 mm.

4. The plastic microchip for microparticle analysis as recited in claim 2,

wherein the upper substrate and the lower substrate are welded by a solvent injected through the respective solvent inlets and then applied along a lower corner portion of the solvent channel including a boundary between the top surface of the lower substrate and the outer surface of the wall of the upper substrate.

5. The plastic microchip for microparticle analysis as recited in claim 1,

wherein respective grooves of horizontal and vertical microlines constituting the negative microgrid pattern have a width of 4 μ

m or less and a depth of 1 μ

m or more.

6. The plastic microchip for microparticle analysis as recited in claim 1,

wherein the upper substrate and the lower substrate are made of a light transmissive plastic having a transmittance of 5% to 100% for a light having a wavelength of 100 to 2,500 nm.

7. The plastic microchip for microparticle analysis as recited in claim 6,

wherein the upper substrate and the lower substrate are made of any one selected from the group consisting of polycarbonate (PC), polymethylmethacrylate (PMMA), polyethylene (PE), polypropylene (PP), polyethyleneterephthalate (PET), polystyrole (PS), cycloolefin (COC) resin and polyolefin (POC) resin.

8. A method for manufacturing a plastic microchip for microparticle analysis including light transmissive upper and lower substrates stacked up and down, an injection chamber formed between the upper and lower substrates, a sample inlet connected to one side of the injection chamber, an outlet connected the other side of the injection chamber, and a microgrid pattern, formed on the top surface of the lower substrate, for counting the number of microparticles in a sample of the injection chamber,

the method comprising the steps of:

(a) manufacturing an upper substrate by injection molding a light transmissive plastic;

(b) manufacturing a lower substrate including a negative microgrid pattern formed on the top thereof by injection molding a light transmissive plastic;

(c) surface-treating the upper substrate and the lower substrate; and

(d) welding the upper substrate and the lower substrate to be stacked up and down.

9. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 8,

wherein, in step (a), the upper substrate having a groove structure, formed adjacent to a wall provided along the whole circumference of the injection chamber on the bottom surface of the upper substrate, and a plurality of solvent inlets formed penetrating the top to be opened in the groove structure;

and

wherein, in step (d), the upper substrate and the lower substrate stacked up and down are solvent-welded by injecting a solvent through the respective solvent inlets into a solvent channel formed by the groove structure and the top surface of the lower substrate, the solvent being injected into a boundary between the upper substrate and the lower substrate.

10. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 9,

wherein the solvent is applied along a lower corner portion of the solvent channel including the top surface of the lower substrate and the outer surface of the wall of the upper substrate.

11. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 9,

wherein the solvent is at least one selected from the group consisting of ketones, aromatic hydrocarbons, halogenated hydrocarbons, and a mixture thereof.

12. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 11,

wherein the solvent is at least one selected from the group consisting of acetone, chloroform, methylene chloride, carbon tetrachloride and a mixture thereof.

13. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 11,

wherein the solvent is a mixture to which an adhesive is added.

14. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 8,

wherein, step (b) comprises the steps of:

stacking a photoresist layer on a plate;

forming a mask pattern having a negative microgrid pattern on the plate by patterning the photoresist layer through exposure and developing processes;

forming an electrically conductive metal layer on the surface on which the mask pattern is formed;

forming a stamper of a metal material, on which a positive microgrid pattern is formed, on the metal layer by performing an electroless plating or electroplating;

separating the stamper from the mask pattern and washing the stamper separated;

processing the resulting stamper through a series of processes of coating a protective layer, polishing the rear side and cutting to a size capable of being fixed to a mold; and

obtaining a lower substrate on which a negative microgrid pattern is formed by mounting the processed stamper on the mold and then injection molding.

15. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 14,

wherein, in the step of forming a metal layer, Cu or Ni is deposited on the surface, on which the mask pattern is formed, by one selected from the group consisting of sputtering, vacuum deposition and electroless plating.

16. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 14,

wherein, in the step of forming a stamper, a stamper of a metal material of Cu or Ni having a thickness of 0.1 mm or more is formed by using an electroless plating or electroplating process.

17. The method for manufacturing a plastic microchip for microparticle analysis as recited in claim 12,

wherein the solvent is a mixture to which an adhesive is added.