Micro-lens imaging multi-well test plate

Abstract

Disclosed is a micro-lens imaging multi-well test plate which comprises: a transparent plate of 3-5 mm in thickness with one or more trapezoidal wells locating in the middle of the plate, each of the wells is of an underside of 2-4 mm in diameter, 0.2-0.5 mm in thickness, a trapezoidal dip angle of 60-75, and has a micro-lens which upper half is hemispherical, lower half is a cylinder, with radius of 0.11.0 mm, height of 0.22.5 mm, molded on the bottom of the well. The micro-lens imaging multi-well test plate is made of homogeneous optical transparent materials. When the trapezoidal concave wells of the test plate are filled with fluid to immerse the micro-lens, under parallel light illumination, due to the refraction effect of light, the image of micro-lens is a round one with an outer edge that is a black ring. The outer radius R of the black ring is the radius of the micro-lens, the inner radius r of the black ring is a function of the refractive index n.sub.1 of the immersion liquid, the refractive index n.sub.2 of the micro-lens and the height h of the micro-lens, so the refractive index of the sample fluid can be determined by monitoring the value of the inner radius r of the black ring with known values of R, n.sub.2 and h. By using a multi-well test plate for imaging, the individual refractive indices of different sample fluids in all the wells can be determined simultaneously in one measurement.

Claims

1. A micro-lens imaging multi-well test plate, comprising: a transparent plate with a thickness of 3 to 5 millimeters; one or more trapezoidal concave wells locating in the middle of the plate surface; and a micro-lens which upper portion is a hemisphere, lower portion is a cylinder attaching on the bottom of each trapezoidal concave well. Said micro-lens is 0.1-1.0 mm in radius (R), 0.2-2.5 mm in the height of the cylindrical part (h); with transparency >90%, optical finish: Ra 0.01-0.05.

2. In a test plate as defined in claim 1 wherein said micro-lens imaging multi-well test plate is made of homogeneous optical transparent materials, such as glassy materials like glass; crystalline materials like quartz and sapphire; synthetic polymers like PMMA and polystyrene.

3. In a test plate as defined in claim 1 wherein said micro-lens is injection molded in one step with said multi-well test plate, or attached to the bottom of said trapezoidal concave well by binding agents.

4. In a test plate as defined in claim 1 wherein said trapezoidal concave well is with an underside of 2.5 mm in diameter, 0.25 mm in thickness, and trapezoidal dip angle of 60-75 for ensuring the liquid surface in the well is a plane surface under the effect of additional pressure on liquid surface.

5. In a test plate as defined in claim 1 wherein said micro-lens imaging multi-well test plate is under hydrophilic treatment with hydrophilic treatment reagents for avoiding molecular adsorption.

6. In a test plate as defined in claim 1 wherein said micro-lens is made of homogeneous optical transparent material which value of refractive index n.sub.2 is greater than the refractive index n.sub.1 of its immersing fluid, such that by the effect of refraction, its image is a round one with a black ring at outer edge, and the inner radius r and outer radius R of said black ring are related to the refractive index n.sub.1 of the fluid as described by equation (1), so the refractive index n.sub.1 of the fluid can be determined by measuring r and R and using equation (1) with an accuracy of 10.sup.6: $\begin{array}{cc}\frac{r}{R}=\sin .Math..Math.-\left(\cos .Math..Math.+\frac{h-R}{R}\right).Math.\frac{\sin .Math..Math..Math.\sqrt{1-k^2.Math.{\sin }^2.Math.}-k.Math..Math.\sin .Math..Math..Math..Math.\cos .Math..Math.}{\cos .Math..Math..Math.\sqrt{1-k^2.Math.{\sin }^2.Math.}+k.Math..Math.{\sin }^2.Math.}& \left(1\right)\end{array}$

7. In a test plate as defined in claim 1 wherein said micro-lens imaging multi-well test plate is of multi-wells in which a micro-lens attaching on the bottom of each well, this enables simultaneous detection on refractive indices of different fluids in every well by taking images of all the micro-lenses in one time.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] For a full understanding of the nature and objects of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which like numerals in the several drawings are employed to denote like parts, and wherein:

[0013] FIG. 1 shows the side view of a 2-path micro-lens imaging multi-well test plate.

[0014] FIG. 2 shows the top view of a 2-path micro-lens imaging multi-well test plate.

[0015] FIG. 3 is the structure of a micro-lens and its image.

[0016] FIG. 4 is the side view of a 16-path micro-lens imaging multi-well test plate.

[0017] FIG. 5 is the top view of a 16-path micro-lens imaging multi-well test plate.

[0018] Referring to FIG. 1, FIG. 2 and FIG. 3, there is shown exemplary micro-lens imaging multi-well test plate 101 for measuring refractive index of a fluid sample, which test plate incorporates the principles of the present invention. In a preferred embodiment, when a small drop of sample solution is dropped into the sample well 102 of said micro-lens imaging multi-well test plate 101 to submerse the micro-lens 103, by the illumination of a parallel light, micro-lens 103 forms an image 302 which is a round image with an outer edge that is a black ring owing to the effect of refraction.

[0019] The values of r and R in the image of micro-lens 202 is related to the refractive index n.sub.1 of the sample fluid, and the refractive index n.sub.2 of the micro-lens as described in the following equation:

[00001]$\begin{array}{cc}\frac{r}{R}=\sin .Math..Math.-\left(\cos .Math..Math.+\frac{h-R}{R}\right).Math.\frac{\sin .Math..Math..Math.\sqrt{1-k^2.Math.{\sin }^2.Math.}-k.Math..Math.\sin .Math..Math..Math..Math.\cos .Math..Math.}{\cos .Math..Math..Math.\sqrt{1-k^2.Math.{\sin }^2.Math.}+k.Math..Math.{\sin }^2.Math.},& \left(1\right)\end{array}$

[0020] where k=n.sub.1/n.sub.2, h is the height of the cylindrical part of the micro-lens, is the incident angle to the spherical surface of the micro-lens.

[0021] The refractive index n.sub.1 of the sample fluid therefore can be obtained with equ.1 by measuring r and R in the image of micro-lens 302.

[0022] Since optical refraction takes place at the speed of light, any instant variation of the refractive index in the solution can immediately induce a change in the radius r of the micro-lens image 302, so by using a high speed camera for imaging, one can monitor instantaneous refractive index change of the sample fluid.

[0023] Since the relative refractive index is a function of solution concentration, and dependent on antigen-antibody reaction or other ligand-receptor reactions, so by monitoring the refractive index variation with time in a solution, one can determine the concentration of the solution as a function of time, or determine whether there is antigen-antibody reaction and the amount of antigen in the sample solution by comparing the refractive indices before and after mixing antigen and antibody solutions together.

[0024] Referring to FIG. 4 and FIG. 5, by taking the images of all the micro-lenses 403 in said micro-lens imaging multi-well test plate 401 at the same time, one can simultaneously determine the individual refractive indices of the sample solutions in all the wells.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

[0025] The following examples and drawings depict an implementation of the presently claimed invention in further detail.

In a First Illustrative Example

[0026] The micro-lens imaging 2-path multi-well test plate comprises: a transparent PMMA plate with thickness of 3.5 mm, two trapezoidal wells which underside is 2.5 mm in diameter, 0.25 mm in thickness, and trapezoidal dip angle is 68; and has a micro-lens with radius of 0.35 mm, height of 1.0 mm molded on the bottom of each well.

[0027] The whole micro-lens imaging multi-well test plate is injection molded in one step, its transparency is >90%, mirror finish is Ra 0.025, and under hydrophilic treatment with a hydrophilic treatment reagent DP-9993 (a terpolymer of polyester-polyether-organosilicon) for 24 hours at room temperature.

[0028] By dropping some sample fluid into said test well to submerse said micro-lens, and placing said micro-lens imaging multi-well test plate under a phase contrast microscope for imaging, an image of said micro-lens is formed with a high resolution digital camera and the refractive index n.sub.1 of the sample fluid is determined by measuring the values of r and R and using equation (1) to an accuracy of 10.sup.6.

In a Second Illustrative Example

[0029] The micro-lens imaging multi-well test plate comprises: a transparent PMMA plate of thickness: 3.75 mm, with 2 trapezoidal wells placing in the middle of the plate which underside is 2.5 mm in diameter, 0.25 mm in thickness, and trapezoidal dip angle is 68; a glass micro-lens with radius of 0.35 mm, height of 1.0 mm is attached on the bottom of each well.

[0030] The glass micro-lens has a transparency of >90%, mirror finish: Ra 0.01, and under hydrophilic treatment with a hydrophilic treatment reagent DP-9993 (a terpolymer of polyester-polyether-organosilicon) for 24 hours at room temperature.

[0031] The micro-lens imaging multi-well test plate is injection molded, its transparency is >90%, mirror finish is Ra 0.025, and under hydrophilic treatment with a hydrophilic treatment reagent DP-9993 (a terpolymer of polyester-polyether-organosilicon) for 24 hours at room temperature.

[0032] By dropping a small drop of clinical sample solution into said test well to submerse said micro-lens, and placing said micro-lens imaging multi-well test plate on a micro-lens imaging apparatus for imaging, an image of said micro-lens is formed and the refractive index n.sub.10 of the solution is determined by measuring the values of r and R and using equation (1), then some antibody solution is added into said test well and a similar procedures are carried on to determine the refractive index n.sub.1 of the solution after adding antibody solution, by deducing the change between n.sub.10 and n.sub.1, the amount of antigen in the sample solution is determined with an accuracy of 10 pg/mL.

In a Third Illustrative Example

[0033] The micro-lens imaging multi-well test plate comprises: a transparent polystyrene plate with thickness of 3.0 mm, and 16 trapezoidal wells which underside is 2.0 mm in diameter, 0.25 mm in thickness, and trapezoidal dip angle is 68; a micro-lens with radius of 0.3 mm, height of 0.85 mm is molded on the bottom of each well.

[0034] The whole micro-lens imaging multi-well test plate is injection molded in one step, its transparency is >90%, mirror finish is Ra 0.05, and under hydrophilic treatment with a hydrophilic treatment reagent DP-9993 (a terpolymer of polyester-polyether-organosilicon) for 24 hours at room temperature.

[0035] By dropping some sucrose solutions into said test wells to submerse said micro-lenses in the wells, and performing imaging on all the micro-lenses at the same time with a micro-lens imaging apparatus, the individual sucrose concentrations of different sucrose solutions in the 16 test wells are determined simultaneously.

[0036] Since certain changes may be made in the above apparatus without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. The presently claimed invention may also be applied in a manner not covered by the above-mentioned cases. Other approaches may also be applied which do not deviate from the essence and spirit of the presently claimed invention. Foreseeable changes, modifications, substitutions, combinations or simplifications can be applied as equivalent methods and are included in the presently claimed invention within the scope of protection.