CN118112241A - Latex microsphere test strip for detecting cryptococcus neoformans and preparation method thereof - Google Patents
Latex microsphere test strip for detecting cryptococcus neoformans and preparation method thereof Download PDFInfo
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Abstract
The invention provides a latex microsphere test strip for detecting cryptococcus neoformans and a preparation method thereof. The test strip comprises a bottom plate, a sample pad, a combination pad, a detection membrane and a water absorption pad which are sequentially fixed on the bottom plate; the combination pad is coated with colored latex microspheres, and the colored latex microspheres are marked by cryptococcus labeled antibodies; the detection membrane is provided with a detection line and a quality control line, the detection line is coated with a cryptococcus coated antibody, and the quality control line is coated with a goat anti-mouse polyclonal antibody. The specificity of the detection test strip can reach 98% -100%, the detection limit is 49CFU, the sensitivity is good, the detection can be completed within 10 minutes, the detection is stable, and the detection test strip has a wide application prospect in the detection field of cryptococcus neoformans.
Description
Technical Field
The invention belongs to the technical field of microorganism detection, and particularly relates to a latex microsphere test strip for detecting cryptococcus neoformans and a preparation method thereof.
Background
Cryptococcosis is a pulmonary or disseminated infectious disease caused by cryptococcus, mainly causing pneumonia and meningitis, and also causing skin, bone or internal organ infections. Cryptococcus neoformans (Cryptoccus neo formans) belong to the genus Cryptococcus and are pathogenic fungi in Cryptococcus. Cryptococcus neoformans are yeast fungi, are covered with a layer of hypertrophic capsules composed of polysaccharide, are not colored by a general staining method, and are difficult to find, so the Cryptococcus neoformans are called as Cryptococcus. Cryptococcus neoformans are widely distributed in nature and are most commonly found in pigeon manure. Infection of cryptococcus neoformans mainly causes subacute or chronic infection of the lung and brain when the human is under immunity. The lung serves as a primary focus and can spread to brain infections, causing chronic inflammation and abscesses.
Since cryptococcus infection is easily misdiagnosed only according to clinical manifestations after it is infected, cryptococcus infection mainly depends on methods such as histopathology, fungus culture, ink staining and serological detection, wherein fungus culture and histopathology detection are not suitable for early diagnosis of infection. The detection method of cryptococcus capsular polysaccharide antigen in serology has high accuracy, high speed and simple operation, and is an early diagnosis method of cryptococcosis. Currently, CN112359126a discloses a method for accurately detecting cryptococcus neoformans, comprising: selecting a sample to be detected, extracting DNA, preparing a real-time fluorescent PCR reaction system, performing fluorescent PCR amplification and the like. CN117143868a discloses a cryptococcus neoformans detection primer set, a kit and application thereof, wherein the cryptococcus neoformans detection primer set comprises a specific primer, and a constant-temperature amplification-nucleic acid colloidal gold chromatography is adopted, so that the early screening and early diagnosis of cryptococcus neoformans infection are facilitated, and the intervention treatment and the disease control are facilitated in time.
However, the detection method or the detection product still has the defects of low specificity, low sensitivity, complex operation and the like, is unfavorable for diagnosis of the cryptococcus neoformans, and provides a detection kit with high speed, sensitivity and high specificity, which is a problem to be solved in the field.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention aims to provide the latex microsphere test strip for detecting the cryptococcus neoformans and the preparation method thereof, and the latex microsphere test strip has higher specificity, good sensitivity and wide application prospect.
To achieve the purpose, the invention adopts the following technical scheme:
In a first aspect, the invention provides a latex microsphere test strip for detecting cryptococcus neoformans, which comprises a bottom plate, and a sample pad, a binding pad, a detection membrane and a water absorption pad which are sequentially fixed on the bottom plate.
Wherein the binding pad is coated with colored latex microspheres, and the colored latex microspheres are marked by cryptococcus labeled antibodies.
The detection membrane is provided with a detection line T and a quality control line C, the detection line is coated with a cryptococcus coated antibody, and the quality control line is coated with a goat anti-mouse polyclonal antibody.
The principle of detecting whether the sample to be detected contains the cryptococcus antigen or not by using the latex microsphere test strip is that the antigen-antibody specificity is combined with the cryptococcus surface specificity antigen, the collected sample is dripped on a sample pad of the test strip, the cryptococcus capsular antigen in the sample can be combined with the monoclonal antibody of the cryptococcus capsular polysaccharide in the reagent strip, and the monoclonal antibody is displayed at a detection line.
As a preferred embodiment of the present invention, the cryptococcus labeled antibody is a monoclonal antibody of cryptococcus.
Preferably, the cryptococcus coated antibody is a monoclonal antibody to cryptococcus. The labeled antibody and the coated antibody are two different cryptococcus monoclonal antibodies. The monoclonal antibody of the cryptococcus can be selected from commercial cryptococcus monoclonal antibody, cryptococcus monoclonal antibody prepared by self synthesis according to the existing sequence or extracted after immune by cryptococcus antigen.
The invention adopts a double antibody sandwich method, and the labeled antibody and the coated antibody are monoclonal antibodies of cryptococcus, which are two different monoclonal antibodies. The double antibody sandwich method has higher sensitivity, and the target molecules are identified and combined by using two different antibodies, so that the specificity of detection is improved. Each antibody binds to a different site of the target molecule, resulting in a reduced likelihood of non-specific binding and thus improved specificity of detection. At the same time, the two antibodies can be simultaneously bound to different sites of the target molecule to form a sandwich structure. This dual binding can significantly increase the binding capacity between the target molecule and the antibody, thereby increasing the sensitivity of the detection. In addition, the double antibody sandwich method can reduce the influence of interferents due to the specific binding of two antibodies when other components (such as proteins, cells and the like) in the sample exist, so that the detection accuracy and sensitivity are improved.
Preferably, the particle size of the colored latex microspheres is 200-400 nm, preferably 200nm, 220nm, 240nm, 250nm, 300nm, 320nm, 350nm, 360nm, 400nm, preferably 300nm.
As a preferable embodiment of the present invention, the detection membrane is a nitrocellulose membrane.
Preferably, the goat anti-mouse polyclonal antibody is a commercial goat anti-mouse polyclonal antibody.
In the invention, the test strip is provided with a C-shaped quality control line, so as to judge whether the test strip can work normally or not; and a "T" test line, representing whether or not cryptococcus infection is detected. During the test, the quality control line of the first bar is not presented, which indicates that the test strip is invalid, and the test strip should be re-detected no matter the second bar is the result. With PBS as a negative control, only the "C" line appears. If the two bars of the line "C" and the line "T" appear, positive is indicated. The deeper the "T" line, the stronger the positive. Conversely, the shallower the "T" line, the less positive.
In a second aspect, the present invention provides a method for preparing the latex microsphere test strip according to the first aspect, the method comprising the following steps:
(1) Marking the color latex microspheres by using cryptococcus labeled antibodies, sealing and diluting the color latex microspheres, spraying the color latex microspheres on a bonding pad, and drying for later use;
(2) Drawing cryptococcus coated antibody and sheep anti-mouse polyclonal antibody on a detection membrane to form a detection line and a quality control line, and drying for later use;
(3) And (3) sequentially assembling the sample pad, the combination pad prepared in the step (1), the detection membrane prepared in the step (2) and the water absorption pad on a bottom plate, and cutting to obtain the latex microsphere test strip.
As a preferable technical scheme of the invention, the marking method in the step (1) comprises the following steps:
Activating and ultrasonically dispersing the color latex microspheres, adding coupling solution to couple with the cryptococcus labeled antibody, centrifuging, discarding supernatant, dispersing the obtained precipitate, adding the coupling solution again to perform secondary coupling, centrifuging, adding sealing solution to seal, and then adding preservation solution to obtain the cryptococcus labeled antibody labeled color latex microspheres.
As a preferred embodiment of the present invention, the activating solution used for the activation is 0.8 to 1.2mg/ml EDC (1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride), and may be, for example, 0.8mg/ml, 0.9mg/ml, 1.0mg/ml, 1.1mg/ml or 1.2mg/ml.
The coupling solution is 0.8-1.2 mg/ml NHS (N-hydroxysuccinimide), and may be, for example, 0.8mg/ml, 0.9mg/ml, 1.0mg/ml, 1.1mg/ml or 1.2mg/ml.
The sealing liquid is Blockmaster DB1130,1130.
Specifically, the test strip of the invention can be prepared by the following method:
(1) Labeling the cryptococcus labeled antibodies with colored latex particles:
2ml centrifuge tube was added with 0.5ml of activating solution and 10. Mu.l of red latex microspheres (pre-use ultrasound); 30 μl of 1mg/ml EDC and 1mg/ml NHS (activated solution dissolution) were placed in a shaker at 37deg.C for 30min; centrifuging for 20min at 14000rpm, and discarding supernatant;
adding 0.6ml of coupling solution, dispersing the microspheres by ultrasonic, centrifuging again for 20min, and discarding the supernatant at 14000 rpm;
Repeating the steps, and adding 60 mug of cryptococcus labeled antibody; placing in a shaking table at 37deg.C for 2.5 hr; centrifuging again for 20min at 14000rpm, and discarding supernatant;
Add 250. Mu.l of blocking solution (DB 1130) and place in a shaker at 37℃for 2h; centrifuging for 20min at 14000rpm, and discarding supernatant;
adding a preservation solution: 600 μl of the microspheres were dispersed by sonication and placed at 4deg.C for use.
(2) And (3) film drawing: diluting goat anti-mouse polyclonal antibody and cryptococcus coated antibody to proper concentrations by using 0.01mol/L PBS (phosphate buffer solution) with pH of 7.4, respectively scribing the goat anti-mouse polyclonal antibody and the cryptococcus coated antibody in a quality control area and a test area of a nitrocellulose membrane by using a scribing instrument, drying at 37 ℃ for 2 hours, and sealing and preserving at room temperature for standby.
(3) Spraying latex: the labeled latex antibody conjugate was diluted to a suitable concentration with 0.05mol/L Borate Buffer (BB) containing 0.1% BSA, pH7.4, sprayed onto glass fibers, dried at 37℃for 2 hours, and stored in a sealed condition at room temperature for use.
(4) And (3) assembling: and respectively pasting the sprayed film, the water absorbing paper, the sprayed latex marked antibody and the glass fiber on a PVC base plate in sequence, and cutting to obtain the latex microsphere test strip.
The following is a specific embodiment for preparing the latex microsphere test strip of the invention:
1. Coupling of latex microspheres and antibodies
First, 10. Mu.l of the red latex microspheres were added to 0.5ml of PBS (0.01 mol/L, pH 6.0), 30. Mu.l of 1mg/ml EDC and 1mg/ml NHS were added, and the mixture was stirred for 30 minutes at 37 ℃.
Subsequently, centrifugation was performed at 14000rpm for 20 minutes, and the supernatant was removed.
Then, 0.6mL of PBS (0.05 mol/L, pH 7.4) was added, the microspheres were dispersed by a water bath sonicator, and then centrifuged at 14000rpm, and after repeating 2 times, 60. Mu.g of cryptococcus monoclonal antibody was added, and after mixing well, the mixture was placed in a shaking table at 37℃for 150min for coupling, 250. Mu.l of blocking solution was added, and the mixture was placed in a shaking table at 37℃for blocking for 2h. Finally, centrifugation was performed at 14000rpm for 20 minutes, the supernatant was removed, and then 1.0mL of PBS (0.05 mol/L, pH 7.4) was added thereto for two repeated operations.
After centrifugation again, the supernatant was discarded, 600. Mu.l of preservation solution was added, and dispersed using a water bath sonicator.
Finally, the sample was placed at 4℃for further use.
2 Assembly of reagent strips
The test strip consists of four parts, namely an NC film, a sample pad, a water absorption pad and a PVC bottom plate.
First, goat anti-mouse polyclonal antibody and cryptococcus coated antibody were diluted to appropriate concentrations with 0.01mol/L PBS at pH 7.4.
Subsequently, a film divider was used to scribe the quality control zone and the test zone of the nitrocellulose film, respectively, and then dried at 37 ℃ for 2 hours.
Next, the labeled latex antibody conjugate was diluted to an appropriate concentration with a borate buffer of 0.05mol/L, pH7.4 containing 0.1% BSA, sprayed onto glass fibers, and dried at 37℃for 2 hours.
Sequentially adhering the sprayed film, the water absorbing paper, the sprayed latex marked antibody and the glass fiber on a PVC base plate, cutting the PVC base plate into proper widths, and loading the PVC base plate into a plastic card to obtain the latex microsphere test strip.
In a third aspect, the present invention also provides a latex microsphere detection kit for detecting cryptococcus neoformans, the latex microsphere detection kit comprising: a detection card, a sample lysate and a latex microsphere test strip according to the first aspect;
The detection card is provided with a detection cavity, a sample adding groove and an observation window which are communicated with the detection cavity, and the latex microsphere test strip is arranged in the detection cavity; the sample pad of the latex microsphere test strip is positioned in the sample adding groove of the detection card, and the detection line and the quality control line are exposed to the observation window of the detection card.
In a fourth aspect, the present invention also provides a method for using a latex microsphere test strip for detecting cryptococcus neoformans, the method comprising: and (3) dripping a sample to be detected onto a sample pad of the latex microsphere test strip in the first aspect or into a sample adding groove of a detection card in the latex microsphere detection kit in the third aspect.
The numerical ranges recited herein include not only the recited point values, but also any point values between the recited numerical ranges that are not recited, and are limited to, and for the sake of brevity, the invention is not intended to be exhaustive of the specific point values that the recited range includes.
Compared with the prior art, the invention has the beneficial effects that:
(1) The specificity is high: the latex microsphere test strip is used for detecting 24 strains of Klebsiella pneumoniae, group B streptococcus, citrobacter freundii, streptococcus grass green, pseudomonas aeruginosa, enterobacter cloacae, moraxella catarrhalis, candida parapsilosis, stenotrophomonas maltophilia, candida albicans, burkholderia, acinetobacter baumannii, staphylococcus aureus, candida otorhinoides, escherichia coli, staphylococcus, candida glabrata, candida krusei, candida tropicalis, candida vinifera, mucor, aspergillus niger, aspergillus, and the like, and only has cross reaction with the candida krusei, wherein the specificity is 98-100%;
(2) High sensitivity and good stability: the detection limit of the cryptococcus neoformans standard strain H99 is 49CFU, and the consistency between independent test results obtained by detection is 100%;
(3) The detection speed is high: detection can be completed within 10 minutes;
Therefore, the latex microsphere test strip for detecting the cryptococcus neoformans provided by the invention has the advantages of high specificity, good sensitivity and stability, and has a wide application prospect.
Drawings
FIG. 1 is a graph showing the detection results of the detection test strips in the sensitivity evaluation test.
Detailed Description
The following embodiments are further described with reference to the accompanying drawings, but the following examples are merely simple examples of the present invention and do not represent or limit the scope of the invention, which is defined by the claims.
In the following examples, reagents and consumables were purchased from conventional reagent manufacturers in the art (e.g., the cryptococcus labeled antibodies and coated antibodies were purchased from Aviva or ABGENT, respectively), unless otherwise specified; unless otherwise indicated, all methods and techniques used are those conventional in the art.
Example 1 preparation of latex microsphere test strip for detection of Cryptococcus neoformans
(1) Labeling the cryptococcus labeled antibodies with colored latex particles:
2ml centrifuge tube was added with 0.5ml of activating solution and 10. Mu.l of red latex microspheres (pre-use ultrasound); 30 μl of 1mg/ml EDC and 1mg/ml NHS (activated solution dissolution) were placed in a shaker at 37deg.C for 30min; centrifuging for 20min at 14000rpm, and discarding supernatant;
adding 0.6ml of coupling solution, dispersing the microspheres by ultrasonic, centrifuging again for 20min, and discarding the supernatant at 14000 rpm;
adding 0.6ml of coupling solution, and dispersing the microspheres by ultrasonic;
Adding 60 mug of cryptococcus labeled antibody; placing in a shaking table at 37deg.C for 2.5 hr to obtain labeled antibody;
Add 250. Mu.l of blocking solution (DB 1130) and place in a shaker at 37℃for 2h; centrifuging for 20min at 14000rpm, and discarding supernatant;
Adding 600 μl of coupling solution, and dispersing the microspheres by ultrasonic; centrifuging again for 20min at 14000rpm, and discarding supernatant;
600 μl of preservation solution was added, and the microspheres were dispersed by sonication at 4deg.C for use.
(2) And (3) film drawing: diluting goat anti-mouse polyclonal antibody and cryptococcus coated antibody to proper concentrations by using 0.01mol/L PBS (phosphate buffer solution) with pH of 7.4, respectively scribing the goat anti-mouse polyclonal antibody and the cryptococcus coated antibody in a quality control area and a test area of a nitrocellulose membrane by using a scribing instrument, drying at 37 ℃ for 2 hours, and sealing and preserving at room temperature for standby.
(3) Spraying latex: the labeled latex antibody conjugate was diluted to a suitable concentration with BB, pH7.4, containing 0.05mol/L of 0.1% BSA, sprayed onto glass fibers, dried at 37℃for 2 hours, and stored in a sealed condition at room temperature for use.
(4) And (3) assembling: and respectively pasting the sprayed film, the water absorbing paper, the sprayed latex marked antibody and the glass fiber on a PVC base plate in sequence, and cutting to obtain the latex microsphere test strip.
Example 2 preparation of specimens
(1) Preparation of culture plate
1L of medium ingredients: 20g glucose, 20g agar, 20g soytone, 10g yeast extract powder were autoclaved using distilled water to a volume of 1L,121 ℃/30 min.
(2) Strain resuscitation
Taking cryptococcus R265 as an example, taking a strain of a refrigerator at-80 ℃, scraping a proper amount of the strain from a bacteria-retaining tube, coating the strain on a solid YPD culture medium, and culturing the strain in a culture box at 30 ℃ for 48 hours.
(3) Preparation of test specimens
Sucking 2ml PBS into a disposable suspension tube, zeroing the turbidimeter, scraping a proper amount of bacterial colonies from a culture plate, fully and uniformly mixing the bacterial colonies in the PBS to form suspension, adjusting the bacterial liquid concentration to 0.5OD as mother solution, and carrying out 2-time gradient dilution for 14 times to 2 -14. 100 μl of the sample to be detected is sucked, dripped into a detection hole of a detection test strip, and the result is read and photographed after standing for 15 min.
Performance evaluation experiment
1. Specificity evaluation
Samples to be tested were prepared according to the sample preparation method described in example 2, and the samples to be tested 1 to 28 and the detection results are shown in table 1:
TABLE 1
Detection conclusion: the reagent strip can be used for specifically detecting cryptococcus and has cross reaction with candida krusei only; the obtained test result accords with the expected result by 98-100%, and the detection time is 10 minutes.
2. Sensitivity evaluation
The measurement results are shown in Table 2 and FIG. 1, which are obtained by measurement of Cryptococcus neoformans standard strain H99.
TABLE 2
| Bacterial liquid concentration (CFU/ml) | Actual colony Count (CFU) | Detection result |
| 2×106 | 3.2×105 | + |
| 106 | 1.6×105 | + |
| 5×105 | 8×104 | + |
| 2.5×104 | 4×104 | + |
| 1.25×105 | 2×104 | + |
| 6.25×104 | 104 | + |
| 3.125×104 | 5×103 | + |
| 1.56×104 | 2.5×103 | + |
| 7800 | 1280 | + |
| 3900 | 640 | + |
| 1950 | 320 | + |
| 975 | 160 | - |
| 490 | 80 | - |
| 240 | 40 | - |
| 120 | 20 | - |
Detection conclusion: the sensitivity (limit of detection) of the kit was 49CFU, and the time taken for detection was 10 minutes.
3. Stability evaluation
The test results are shown in Table 3, and the test results are determined by Cryptococcus neoformans standard strain H99; wherein the test results 1, 2 and 3 represent 3 replicates.
TABLE 3 Table 3
| Bacterial liquid concentration (CFU/ml) | Actual colony Count (CFU) | Detection result 1 | Detection result 2 | Detection result 3 |
| 2×106 | 3.2×105 | + | + | + |
| 106 | 1.6×105 | + | + | + |
| 5×105 | 8×104 | + | + | + |
| 2.5×104 | 4×104 | + | + | + |
| 1.25×105 | 2×104 | + | + | + |
| 6.25×104 | 104 | + | + | + |
| 3.125×104 | 5×103 | + | + | + |
| 1.56×104 | 2.5×103 | + | + | + |
| 7800 | 1280 | + | + | + |
| 3900 | 640 | + | + | + |
| 1950 | 320 | + | + | + |
| 975 | 160 | - | - | - |
| 490 | 80 | - | - | - |
| 240 | 40 | - | - | - |
| 120 | 20 | - | - | - |
Detection conclusion: the consistency between the independent test results obtained was 100% consistency, and the time taken for the test was 10 minutes.
In conclusion, the latex microsphere test strip has the detection specificity of 98% -100%, the detection sensitivity is high, the detection limit is 49CFU, the detection stability is stable, and the detection can be completed within 10 minutes.
The applicant declares that the above is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be apparent to those skilled in the art that any changes or substitutions that are easily conceivable within the technical scope of the present invention disclosed by the present invention fall within the scope of the present invention and the disclosure.
Claims (10)
1. The latex microsphere test strip for detecting the cryptococcus neoformans is characterized by comprising a bottom plate, and a sample pad, a binding pad, a detection membrane and a water absorption pad which are sequentially fixed on the bottom plate;
the combination pad is coated with colored latex microspheres, and the colored latex microspheres are marked by cryptococcus labeled antibodies;
the detection membrane is provided with a detection line and a quality control line, the detection line is coated with a cryptococcus coated antibody, and the quality control line is coated with a goat anti-mouse polyclonal antibody.
2. The latex microsphere test strip according to claim 1, wherein the cryptococcus labeled antibody is a monoclonal antibody to cryptococcus;
The cryptococcus coated antibody is a monoclonal antibody to cryptococcus and is distinguished from the labeled antibody.
3. The latex microsphere test strip according to claim 1 or 2, wherein the particle size of the colored latex microspheres is 200-400 nm.
4. The latex microsphere test strip according to any one of claims 1-3, wherein the detection membrane is a nitrocellulose membrane.
5. A method for preparing the latex microsphere test strip according to any one of claims 1 to 4, comprising the steps of:
(1) Marking the color latex microspheres by using cryptococcus labeled antibodies, sealing and diluting the color latex microspheres, spraying the color latex microspheres on a bonding pad, and drying for later use;
(2) Drawing cryptococcus coated antibody and sheep anti-mouse polyclonal antibody on a detection membrane to form a detection line and a quality control line, and drying for later use;
(3) And (3) sequentially assembling the sample pad, the combination pad prepared in the step (1), the detection membrane prepared in the step (2) and the water absorption pad on a bottom plate, and cutting to obtain the latex microsphere test strip.
6. The method of claim 5, wherein the labeling in step (1) is performed by:
activating and ultrasonically dispersing the color latex microspheres, adding coupling solution to couple with the cryptococcus labeled antibody, centrifuging, discarding supernatant, dispersing the obtained precipitate, adding the coupling solution again to perform secondary coupling, centrifuging, adding sealing solution to seal, and then adding preservation solution to obtain the cryptococcus labeled antibody labeled color latex microspheres.
7. The process according to claim 6, wherein the activating liquid used for the activation is 0.8 to 1.2mg/ml EDC;
the coupling liquid is 0.8-1.2 mg/ml NHS;
The sealing liquid is Blockmaster DB1130,1130.
8. The preparation method according to claim 6, characterized in that the preparation method comprises the steps of:
(1) Mixing the color latex microsphere with a solution containing 0.8-1.2 mg/ml EDC and 0.8-1.2 mg/ml NHS, adding the cryptococcus labeled antibody, mixing, activating and coupling at 37 ℃, centrifuging, and removing the supernatant; dispersing the collected precipitate, repeating the steps of activation and coupling to obtain the color latex microspheres marked by the cryptococcus labeled antibody, sealing and diluting the color latex microspheres, spraying the color latex microspheres on a bonding pad, and drying for later use;
(2) Drawing cryptococcus coated antibody and sheep anti-mouse polyclonal antibody on a detection membrane to form a detection line and a quality control line, and drying for later use;
(3) And (3) sequentially assembling the sample pad, the combination pad prepared in the step (1), the detection membrane prepared in the step (2) and the water absorption pad on a bottom plate, and cutting to obtain the latex microsphere test strip.
9. A latex microsphere detection kit for detecting cryptococcus neoformans, comprising: a test card, a sample lysate, and a latex microsphere test strip according to any one of claims 1 to 4;
The detection card is provided with a detection cavity, a sample adding groove and an observation window which are communicated with the detection cavity, and the latex microsphere test strip is arranged in the detection cavity; the sample pad of the latex microsphere test strip is positioned in the sample adding groove of the detection card, and the detection line and the quality control line are exposed to the observation window of the detection card.
10. The application method of the latex microsphere test strip for detecting the cryptococcus neoformans is characterized by comprising the following steps of: a sample to be measured is dripped on a sample pad of the latex microsphere test strip according to any one of claims 1 to 4 or dripped into a sample adding groove of a detection card in the latex microsphere detection kit according to claim 9.
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