CN111982818A - A device for detecting optical digitized signals of liquid crystal droplets and its application - Google Patents

Abstract

The invention relates to a device for detecting optical digitized signals of liquid crystal droplets and its application, comprising a display, a detector, a condensing tube, an analyzer, a sample slot and a bottom plate connected in sequence from top to bottom; the sample slot is a hollow cylinder There is a partition plate in the cavity cylinder, and a light hole is arranged in the center of the partition plate. The partition plate divides the inner space of the cavity cylinder into an upper chamber and a lower chamber, and the side wall of the upper chamber The upper chamber is provided with an opening, and a polarizer, a light homogenizer and a light source are placed in the lower chamber. The detection device of the present invention mainly includes biological molecules such as enzymes, proteins, small molecules, etc., and chemical substances such as heavy metals, inorganic pollutants, organic pollutants, etc., in liquid crystal droplets as sensing elements. It has the advantages of strong portability, real-time dynamic detection, high detection efficiency, and requires less sample volume, avoiding the shortcomings of traditional detection requiring large laboratory instruments and complex data processing.

Description

A device for detecting optical digitized signals of liquid crystal droplets and its application

technical field

The invention relates to a device for detecting optical digitized signals of liquid crystal droplets and its application, and belongs to the technical field of sensing detection equipment.

Background technique

Since the liquid crystal material has the fluidity of the liquid and the anisotropy of the crystal, especially the optical anisotropy, the recognition unit is modified on the liquid-liquid interface or the liquid-solid interface of the liquid crystal, and the liquid crystal molecule is changed through the recognition of the target by the recognition unit. The arrangement of polarized light signals changes from light to dark or from dark to light, which can realize fast, sensitive, portable detection of targets or identification of responses to external stimuli. The targets mainly include biomolecules such as enzymes, proteins, small molecules, etc., and chemical substances such as heavy metals, inorganic pollutants, organic pollutants, etc. External stimulus responses include heat, electricity, and magnetism. Therefore, the field of detection based on the principle of liquid crystal sensing is booming.

However, the quantitative or qualitative detection of the target concentration often requires the use of a polarized light microscope to capture polarized light signal images. For example, Chinese patent document CN110554493A provides a polarized light reading microscope, which includes: an eyepiece, a lens barrel, a lens barrel movement adjustment mechanism, An objective lens, a base, a tablet clamp, a worktable, and a strut group connecting the base and the lens barrel moving and adjusting mechanism, the base is provided with a light source disposed toward the lens barrel, and a light source is provided above the light source The polarizer of the base is detachably connected, and the outer periphery of the objective lens is sleeved with an analyzer matched with the polarizer. The above-mentioned polarized light reading microscope can be used as an ordinary optical microscope, and can also be used as a polarized light microscope, so that one mirror can be used for multiple purposes, and the equipment cost and the space occupied by the equipment are reduced. Then, the gray value or brightness ratio is calculated by image processing software such as Image J or Photoshop. The data result needs to be converted, and the steps are more complicated. The liquid crystal droplet detection realizes the semi-quantitative detection of the target through the transformation of the droplet shape, such as the direct change from the "Malta cross" shape to the "fan shape" shape. Due to the small size of the liquid crystal droplet, about micrometers The image obtained by the polarizing microscope shows a small range of changes and cannot be representative of the sample.

However, traditional polarizing microscopes are expensive, expensive, and complex in structure, and are suitable for use in indoor environments such as laboratories. Therefore, there is an urgent need to develop a portable detection device based on the liquid crystal sensing principle that can directly read the detection results, so as to realize the rapid real-time detection of the target.

SUMMARY OF THE INVENTION

Aiming at the deficiencies of the prior art, the present invention provides a device for detecting optical digitized signals of liquid crystal droplets, which is convenient to carry, facilitates outdoor detection or home self-inspection, and facilitates instrument maintenance and consumables replacement.

The technical scheme of the present invention is as follows:

A device for detecting optical digitized signals of liquid crystal droplets, comprising a display, a detector, a condensing tube, an analyzer, a sample slot and a bottom plate connected in sequence from top to bottom, and the display and the detector are electrically connected;

The sample tank is a hollow cylinder, a partition plate is arranged in the hollow cylinder, a light-passing hole is arranged in the center of the partition plate, and the partition plate divides the inner space of the hollow cylinder into an upper chamber and a lower chamber, The side wall of the upper chamber is provided with an opening, and a polarizer, a light homogenizer and a light source are placed in the lower chamber.

Preferably, the light source is an LED light source with adjustable light intensity.

Preferably, the LED light source is a circular or annular light source with a power of 1-5W.

Preferably, the light-emitting angle of the LED light source is between 60° and 120°.

Preferably, the distance between the light source and the light-transmitting hole is 3-15 cm. The benefit of this design is that maintaining a reasonable distance can reduce the disturbance of the sample caused by the thermal effect of the light source.

Preferably, the center of the light through hole is coaxial with the center of the light source. The advantage of this design is that liquid crystal droplets and other detection samples are placed in the upper chamber, and the light emitted by the light source directly passes through the coaxial light hole and irradiates the liquid crystal droplet. The center of the light source is coaxial with the light hole, which is convenient for detection. .

Preferably, the polarization axis angles of the polarizer and the analyzer are orthogonal to 90°. Orthogonal 90° means that the polarization axis direction of the analyzer is relative to the polarization axis direction of the polarizer.

Preferably, the analyzer includes a polarizer, a pressure ring and a rotating assembly, the polarizer is enclosed in the pressure ring, the pressure ring is detachable, and the optical axis angle of the polarizer is adjusted through the rotating assembly. The advantage of this design is that during long-term use, impurities in the environment are likely to cause pollution, and the polarizer assembly needs to be cleaned or replaced regularly. The detachable pressure ring facilitates the replacement of the polarizer, and the polarizer axis can be adjusted by rotating the assembly. The angle of the optical axis of the polarizer polarizer is adjusted to 90°.

Preferably, the polarizer includes a polarizer and a pressing ring, the polarizer is enclosed in the pressing ring, and the pressing ring is detachable. The advantage of this design is that during long-term use, due to impurities in the environment, the polarizer assembly needs to be regularly cleaned or replaced. The detachable pressure ring facilitates the replacement of the polarizer.

Preferably, the distance between the light homogenizing sheet and the light source is 1-3 cm.

Preferably, the distance between the condensing tube and the sample tank is 5-20 cm.

Preferably, the device further comprises a light-blocking plate, and the width of the light-blocking plate is larger than the diameter of the light-transmitting hole. The benefit of this design is that the baffle can be inserted through the opening into the upper chamber of the sample well, covering the light-passing hole.

A method for using a device for detecting optical digitized signals of liquid crystal droplets, comprising the following steps:

Step 1. Zero calibration:

Turn on the light source, fix the intensity of the light source, and place a baffle plate in the sample tank. At this time, the light signal of the light source on the optical axis passes through the light homogenizer, the polarizer, the baffle plate and the analyzer in sequence, and the light intensity is detected by the detector. At this time, the display shows the number Then remove the baffle, and the display should remain at zero. If it is not zero, the relative angle between the polarizer and the analyzer is deviated, and the deflection angle of the analyzer needs to be adjusted to make the display display zero. Insert the baffle plate into the sample tank, and the number is still zero; adjust the deflection angle of the analyzer through the above steps to ensure that the sample tank base and the environmental contrast zero point have no effect;

Step 2. Preparation of sensing primitives:

The sensing element is a liquid crystal droplet fixed on a substrate, where the substrate is a hydrophobic interface, and the liquid crystal droplet is anchored on the hydrophobic interface. The incident polarized light will not be deflected, so the illuminance value of the sample should be zero at this time;

By designing detection methods for different substances, including but not limited to enzymes, small molecules, and heavy metals, doping or modifying liquid crystal droplets to obtain sensing primitives with specific recognition;

Step 3. Sample test:

Drop 1 μL of the sample containing the target on the specific recognition sensing element, remove the light shield, insert the sensing element sheet into the sample tank, the liquid crystal molecular arrangement changes, and 0-1 can be detected within 5-10 minutes. Or the change of the detection signal of 1-0, in which 0 represents the illuminance value is zero, 1 represents the illuminance value has indication, and the detection limit of the sensing element is ^10-9 and below.

The beneficial effects of the present invention are:

1. The detection device of the present invention has the advantages of strong portability, real-time dynamic detection, high detection efficiency, and less sample volume when liquid crystal droplets are used as sensing elements to detect biological substances, which avoids the need for large-scale laboratory instruments, Disadvantages such as complex data processing.

2. The device combination setting of the liquid crystal droplet detection device of the present invention is mainly an integrated integrated device and an auxiliary regular maintenance module. The polarizer and the analyzer are replaceable and disassembled units, which is convenient for the maintenance of the instrument and the replacement of consumables. replace.

3. The detection device of the present invention is based on the principle of illuminance meter, and realizes real-time digital statistics of detection data results according to the identification of the target object by liquid crystal droplets.

4. The detection device of the present invention has a simple process, and as a liquid crystal sensing portable detection device, it can realize outdoor detection or home self-inspection, has good economic value and social benefit, and is worthy of popularization and application.

Description of drawings

Fig. 1 is the structural representation of the detection device of the present invention;

Fig. 2 is the perspective view of the sample tank in the present invention;

Fig. 3 is the front view of the sample tank in the present invention;

Fig. 4 is the top view of the sample tank in the present invention;

Fig. 5 is the perspective view of the baffle plate in the present invention;

Among them: 1-detector, 2-concentrator, 3-analyzer, 4-sample slot, 5-bottom plate, 6-opening, 7-display, 8-light hole, 9-upper chamber, 10- Light barrier.

Detailed ways

The present invention will be further described below with reference to the embodiments and the accompanying drawings, but is not limited thereto.

Example 1:

As shown in FIG. 1 , this embodiment provides a device for detecting optical digitized signals of liquid crystal droplets, including a display 7 , a detector 1 , a condenser tube 2 , an analyzer 3 , and a sample tank 4 connected in sequence from top to bottom and the bottom plate 5, the display 7 is electrically connected with the detector 1, wherein the display 7, the detector 1, and the condensing tube 2 constitute the illuminance meter as a whole;

The sample tank 4 is a hollow cylinder, a partition plate is arranged in the hollow cylinder, a light-passing hole 8 is arranged in the center of the partition plate, and the partition plate divides the inner space of the hollow cylinder into an upper chamber and a lower chamber The side wall of the upper chamber is provided with an opening 6, and a polarizer, a light homogenizer and a light source are placed in the lower chamber.

Among them, the analyzer 3 and the sample tank 4 are glued together. The light source, light homogenizer and polarizer are placed in the lower chamber, and then the bottom plate 5 is directly inserted into the bottom end of the lower chamber for encapsulation. sense primitives.

Both the detector 1 and the condensing tube 2 form part of the illuminance meter. The light source is an LED circular light source with adjustable light intensity, the power is 1W, and the luminous angle of the LED light source is between 60-120°.

The distance between the light-passing hole 8 and the light source is 3-15 cm. Maintaining a reasonable distance between the two can reduce the interference of the thermal effect generated by the light source on the sample.

The display 7, the detector 1, and the condensing tube 2 constitute a commercially available illuminance meter. The manufacturer and model are Taiwan Taishi tes-137. The distance between the condensing tube 2 and the sample tank 4 is 5-20 cm.

The light-passing hole 8 of the sample tank is coaxial with the center of the light source. In the upper chamber, sensing elements such as liquid crystal droplets can be placed for sample detection. The light emitted by the light source directly passes through the coaxial light hole 8 and illuminates the liquid crystal droplet. The center of the light source is coaxial with the center of the light hole. , for easy detection.

The polarizer and the analyzer 3 are mainly composed of linear polarizers, and the polarization optical axis angles of the polarizer and the analyzer are orthogonal to 90°. Orthogonal 90° means that the polarization axis direction of the analyzer is relative to the polarization axis direction of the polarizer.

Specifically, the analyzer 3 includes a polarizer, a pressure ring and a rotating assembly, the polarizer is enclosed in the pressure ring, the pressure ring is detachable, and the optical axis angle of the polarizer is adjusted by the rotating assembly. During long-term use, due to impurities in the environment, the polarizer assembly needs to be cleaned or replaced regularly. The detachable pressure ring facilitates the replacement of the polarizer, and the polarizer axis can be adjusted relative to the polarizer polarizer axis by rotating the assembly. Angle, adjust to 90°, crush and rotate assembly as conventional equipment.

The polarizer includes a polarizer and a pressing ring, the polarizer is enclosed in the pressing ring, and the pressing ring is detachable. During long-term use, due to impurities in the environment, the polarizer assembly needs to be cleaned or replaced regularly. The detachable pressure ring facilitates the replacement of the polarizer.

The distance between the homogenizing sheet and the light source is 1-3 cm, and the homogenizing sheet, the light source and the polarizer are fixed by gluing or nuts.

The detection device further includes a light shielding plate 10, and the width of the light shielding plate 10 is larger than the diameter of the light-transmitting hole. The light shielding plate 10 is a long black plate, and the light shielding plate can be inserted into the upper chamber of the sample tank from the opening to cover the light passage hole.

The working principle of the present invention:

Combined with the principle of photoelectric conversion and the principle of liquid crystal anisotropy, the optical signal of the liquid crystal detection target object is converted into an electrical signal through the photoelectric conversion element, and the data of the liquid crystal sensing detection result of the target object is realized.

Example 2:

Example 1 is repeated, except that the LED light source is a ring light source with a power of 5W.

Example 3:

Using the device for detecting the optical digital signal of liquid crystal droplets described in Embodiment 1, the qualitative detection of surfactant is carried out, and the detection method includes the following steps:

Step 1. Zero calibration:

Turn on the light source, fix the intensity of the light source, and place a baffle plate in the sample tank. At this time, the light signal of the light source on the optical axis passes through the light homogenizer, the polarizer, the baffle plate and the analyzer in sequence, and the light intensity is detected by the detector. At this time, the display shows the number Then remove the baffle, and the display should remain at zero. If it is not zero, the relative angle between the polarizer and the analyzer is deviated, and the deflection angle of the analyzer needs to be adjusted to make the display display zero. Insert the baffle plate into the sample tank, and the number is still zero; adjust the deflection angle of the analyzer through the above steps to ensure that the sample tank base and the environmental contrast zero point have no effect;

Step 2. Preparation of sensing primitives:

The sensing element is 4-cyano-4'-pentylbiphenyl (5CB) or mixed liquid crystal (E7) and other liquid crystal materials are prepared into uniform liquid crystal droplets by solvent evaporation method, inkjet printing method, etc., and the substrate is eighteen Hydrophobic interface modified by alkyltrichlorosilane-heptane (OTS), N-dimethyl-N-octadecyl-3-aminopropyltrimethylsilyl chloride (DMOAP) and other materials;

Step 3. Sample test:

1 μL of buffered saline solution without surfactant (sample 1) and 1 μL of buffered saline solution with different concentrations of surfactant (samples 2-5, respectively, 0.001 mM, 0.01 mM) were added dropwise to the sensing element. , 0.1mM, 1mM). The sensing element is placed in the sample well and read through the display. Because sample 1 induces a change in the alignment of liquid crystal molecules, showing a "Malta cross" shape; while the surfactants in samples 2-5 have a hydrophobic interaction with liquid crystal molecules, which induces liquid crystal molecules to align along the interface. With increasing, the liquid crystal droplet shape gradually changed from "Malta cross" shape to "fan shape" shape, and the display number showed a trend of first decreasing and then increasing. The qualitative detection of surfactant was realized through the illuminance-concentration trend graph.

Example 4:

Using the device for detecting the optical digital signal of liquid crystal droplets described in Embodiment 1, the detection of lysozyme is carried out, and the detection method comprises the following steps:

Step 1. Zero calibration:

Turn on the light source, and fix the intensity of the light source, and place a baffle plate in the sample tank. At this time, the light signal of the light source on the optical axis passes through the light homogenizer, the polarizer, the baffle plate and the analyzer in sequence, and the light intensity is detected by the detector. At this time, the display shows The number is zero; then remove the baffle, and the display should remain zero. If it is not zero, the relative angle of the polarizer and the analyzer is deviated, and the deflection angle of the analyzer needs to be adjusted to make the display display zero; Insert the baffle plate into the sample tank, and the number is still zero; adjust the deflection angle of the analyzer through the above steps to ensure that the sample tank base and the environmental contrast zero point have no effect;

Step 2. Preparation of sensing primitives:

The sensing element is 4-cyano-4'-pentylbiphenyl (5CB) or mixed liquid crystal (E7) and other liquid crystal materials are prepared into uniform liquid crystal droplets by solvent evaporation method, inkjet printing method, etc., and the substrate is eighteen Hydrophobic interface modified by alkyltrichlorosilane-heptane (OTS), N-dimethyl-N-octadecyl-3-aminopropyltrimethylsilyl chloride (DMOAP) and other materials;

Step 3. Sample test:

The specific hydrolysis of dodecyl glucopyranoside by lysozyme is used to realize the detection of lysozyme by liquid crystal droplets. Through the response of the sensing element to different concentrations of dodecyl glucopyranoside solution, the concentration of dodecyl glucopyranoside solution with the illumination value of 0 is screened out, and the different concentrations of lysozyme and the concentration of dodecane are combined. After incubation at constant temperature, the glucopyranoside solution was added to the sensing element as a sample, and the sensing element was put into the sample tank and read through the display. When the concentration of lysozyme is greater than or equal to 0.01mg/mL, that is, the activity is greater than or equal to 200U/mL, the display number is greater than 0, while other enzymes are incubated with the same concentration of dodecyl glucopyranoside solution, the display number is still 0 , to achieve rapid and specific detection of lysozyme.

The above are only specific embodiments of the present invention, and the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are all should be included within the protection scope of the present invention.

Claims (10)

1. a device for detecting the optical digitized signal of liquid crystal droplets, is characterized in that, comprising a display and a detector, a concentrator, an analyzer, a sample tank and a bottom plate connected sequentially from top to bottom, the display is electrically connected with the detector ; The sample tank is a hollow cylinder, a partition plate is arranged in the hollow cylinder, a light-passing hole is arranged in the center of the partition plate, and the partition plate divides the inner space of the hollow cylinder into an upper chamber and a lower chamber, The side wall of the upper chamber is provided with an opening, and a polarizer, a light homogenizer and a light source are placed in the lower chamber. 2 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the light source is an LED light source with adjustable light intensity. 3 . 3 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 2 , wherein the light-emitting angle of the LED light source is between 60° and 120°. 4 . 4 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the distance between the light source and the light-passing hole is 3-15 cm. 5 . 5 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the center of the light-passing hole is coaxial with the center of the light source. 6 . 6 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the polarization axis angles of the polarizer and the analyzer are orthogonal to 90°. 7 . 7 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the analyzer comprises a polarizer, a pressure ring and a rotating assembly, the polarizer is enclosed in the pressure ring, and the pressure ring is detachable. 8 . , adjust the optical axis angle of the polarizer by rotating the component. 8 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the polarizer comprises a polarizer and a pressure ring, the polarizer is enclosed in the pressure ring, and the pressure ring is detachable. 9 . 9 . The device for detecting optical digitized signals of liquid crystal droplets according to claim 1 , wherein the device further comprises a light-shielding plate, and the width of the light-shielding plate is greater than the diameter of the light-transmitting hole. 10 . 10. A method for using a device for detecting optical digitized signals of liquid crystal droplets as claimed in any one of claims 1-9, characterized in that, comprising the following steps: Step 1. Zero calibration: Turn on the light source, fix the intensity of the light source, and place a baffle plate in the sample tank. At this time, the light signal of the light source on the optical axis passes through the light homogenizer, the polarizer, the baffle plate and the analyzer in sequence, and the light intensity is detected by the detector. At this time, the display shows the number Then remove the baffle, and the display should remain at zero. If it is not zero, the relative angle between the polarizer and the analyzer is deviated, and the deflection angle of the analyzer needs to be adjusted to make the display display zero. Insert the baffle plate into the sample tank, and the number is still zero; adjust the deflection angle of the analyzer through the above steps to ensure that the sample tank base and the environmental contrast zero point have no effect; Step 2. Preparation of sensing primitives: The sensing element is a liquid crystal droplet fixed on a substrate, where the substrate is a hydrophobic interface, and the liquid crystal droplet is anchored on the hydrophobic interface. The incident polarized light will not be deflected, so the illuminance value of the sample should be zero at this time; By designing detection methods for different substances, including but not limited to enzymes, small molecules, and heavy metals, doping or modifying liquid crystal droplets to obtain sensing primitives with specific recognition; Step 3. Sample test: Drop 1 μL of the sample containing the target on the specific recognition sensing element, remove the light shield, insert the sensing element sheet into the sample tank, the liquid crystal molecular arrangement changes, and 0-1 can be detected within 5-10 minutes. Or the change of the detection signal of 1-0, in which 0 represents the illuminance value is zero, 1 represents the illuminance value has indication, and the detection limit of the sensing element is ^10-9 and below.

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