Claims:We claim:

1. A microfluidic cartridge (100) for smearing biological fluid, the cartridge (100) comprising:
a base plate (1) defining a flow surface;
a coverslip (5) positioned above the base plate (1), to define a chamber (2) on the flow surface of the base plate (1) for receiving the biological fluid, the coverslip (5) is configured to conceal at least a portion of the chamber (2), wherein the chamber (2) is defined with a width (W);
an inlet section (3a) defined at one end (4a) of the chamber (2) for introducing the biological fluid; and
an outlet section (3b) defined at another end (4b) opposite to the one end (4a) of the chamber (2), wherein the outlet section (3b) extending from the another end (4b) of the chamber (2) to a length (Lo) ranging from 0% to 200% of the width (W) of the chamber (2).

2. The cartridge (100) as claimed in claim 1, comprises a tail portion (6) defined at the outlet section (3b), wherein length of the tail portion (6) is equal to the length (Lo) of the outlet section (3b).

3. The cartridge (100) as claimed in claim 1, comprises a spacer element (7), positioned between the base plate (1) and the cover slip (5), wherein, the spacer element (7) defines the chamber (2), the inlet section (3a) and the outlet section (3b).

4. The cartridge (100) as claimed in claim 1, wherein the inlet section (3a) and the outlet section (3b) are defined at opposing sides of the coverslip (5).

5. The cartridge (100) as claimed in claim 1, wherein flow of biological fluid between the inlet section (3a) and the outlet section (3b) is balanced by capillary force and an atmospheric pressure.

6. The cartridge (100) as claimed in claim 1, wherein a surface tension of the biological fluid ranges from 15mN/m to 85mN/m.
7. The cartridge (100) as claimed in claim 1, wherein a length (L) of chamber (2) ranges from about 50% to about 300% of the width (W) of the chamber (2).

8. The cartridge (100) as claimed in claim 1, wherein the depth of the chamber (2) ranges from about 5µm to about 50µm.

9. The cartridge (100) as claimed in claim 1, wherein width (Wo) of the tail portion (6) is at least 0.5mm.

10. The cartridge (100) as claimed in claim 1, wherein the base plate (1) and the coverslip (5) are made of material including at least one of glass and a polymeric material.

11. The cartridge (100) as claimed in claim 1, comprises a coating surface, applied on the base plate (1) and the cover slip (5), wherein the coating surface is configured to vary a contact angle of the biological fluid with the base plate (1) and the cover slip (5).

12. The cartridge (100) as claimed in claim 11, wherein the contact angle of the biological fluid ranges from about 10° to about 40°.

13. A microfluidic chamber assembly (200), comprising:
a plurality of microfluidic cartridges (100) as claimed in claim 1,
wherein, at least one microfluidic cartridge of the plurality of microfluidic cartridges (100) is configured to receive a stained biological fluid.

14. The microfluidic chamber assembly (200) as claimed in claim 12, wherein at least one of the plurality of microfluidic cartridges (100) is configured to receive an un-stained biological fluid.

15. A microfluidic assay (200), comprising:
a plurality of microfluidic cartridges (100) as claimed in claim 1; and
at least one bio-chemical cartridge (125).

16. The microfluidic assay (200) as claimed in claim 15, wherein the at least one bio-chemical cartridge (125) includes a plurality of bio-chemical chambers (175).

17. The microfluidic assay (200) as claimed in claim 16, wherein at least one of the plurality of bio-chemical chambers (175) is a test chamber (150a).

18. The microfluidic assay (200) as claimed in claim 16, wherein at least one of the plurality of bio-chemical chambers (175) is a control chamber (150b).

Dated 31st day of October 2019

Gopinath Arenur Shankararaj
OF K & S PARTNERS
AGENT FOR THE APPLICANT(S)
IN/PA-1852
, Description: