Search

CN-122011472-A - Nitrocellulose membrane, preparation method and application thereof

CN122011472ACN 122011472 ACN122011472 ACN 122011472ACN-122011472-A

Abstract

The invention relates to the technical field of immunodetection, and discloses a treatment method of a nitrocellulose membrane, which comprises plasma treatment, wherein the nitrocellulose membrane is subjected to the plasma treatment, and polyvinylpyrrolidone is used for coating, and the nitrocellulose membrane subjected to the plasma treatment is coated with polyvinylpyrrolidone. The invention realizes improvement of hydrophilicity, antibody binding rate, chromatographic speed change rate, polyvinylpyrrolidone layer firmness and/or streak diffusion rate in low humidity environment.

Inventors

  • LIU JIAN
  • CHEN WEISHAO
  • XIA XIAOLI
  • DENG LI

Assignees

  • 洁科膜过滤技术(杭州)有限公司

Dates

Publication Date
20260512
Application Date
20251231

Claims (10)

  1. 1. A method for treating a nitrocellulose membrane, comprising: A plasma treatment in which the nitrocellulose membrane is subjected to a plasma treatment, and, Polyvinylpyrrolidone coating, wherein a nitrocellulose membrane subjected to plasma treatment is coated with polyvinylpyrrolidone.
  2. 2. A process according to claim 1, characterized in that in the plasma treatment argon and oxygen are used in a volume ratio of 3:1-5:1, optionally 4:1, and/or the power is 50-100W, and/or the treatment time is 30-150 seconds, and/or the vacuum is 10-50Pa.
  3. 3. The process according to claim 1 or 2, characterized in that in the polyvinylpyrrolidone coating a polyvinylpyrrolidone solution with a concentration of 0.3g/100ml-2.5g/100ml is used, optionally a polyvinylpyrrolidone solution with a concentration of 0.3g/100ml-2.5g/100ml contains 0.025 g/100ml-0.15 g/100ml of cross-linking agent; Still optionally, the solvent in the polyvinylpyrrolidone solution with the concentration of 0.3g/100ml to 2.5g/100ml is deionized water and/or ethanol, and further optionally, the solvent in the polyvinylpyrrolidone solution with the concentration of 0.3g/100ml to 2.5g/100ml is deionized water and ethanol with the volume ratio of 9:1.
  4. 4. A process according to any one of claims 1 to 3, wherein the molecular weight of polyvinylpyrrolidone is greater than 1.5 and less than 13 tens of thousands, optionally the molecular weight of polyvinylpyrrolidone is greater than 3 and less than 13 tens of thousands, further preferably the molecular weight of polyvinylpyrrolidone is 3.8 tens of thousands; Still optionally, the cross-linking agent is glutaraldehyde or genipin.
  5. 5. The process of any one of claims 1 to 4, further comprising the step of drying the polyvinylpyrrolidone coated nitrocellulose membrane, optionally at 60 ℃.
  6. 6. The method according to any one of claims 1 to 5, wherein the polyvinylpyrrolidone coating is performed by placing the nitrocellulose membrane subjected to the plasma treatment in a polyvinylpyrrolidone solution for 10 to 30 seconds.
  7. 7. A treatment method according to any one of claims 1-5, characterized in that at least one of the following is fulfilled: In plasma processing, the power is 50W, 80W, or 100W; In plasma treatment, the treatment time is 30, 90, 120 or 150 seconds; in the plasma treatment, the vacuum degree is 10 Pa, 30 Pa, or 50Pa; In the polyvinylpyrrolidone coating, a polyvinylpyrrolidone solution having a concentration of 0.3g/100ml, 0.5g/100ml, 1g/100ml, 1.5g/100ml, 2g/100ml or 2.5g/100ml is used; in the polyvinylpyrrolidone coating, the polyvinylpyrrolidone solution having a concentration of 0.3g/100ml to 2.5g/100ml contains 0.025 g/100ml, 0.1. 0.1 g/100ml or 0.15. 0.15 g/100ml of the crosslinking agent.
  8. 8. A nitrocellulose membrane prepared by the treatment method of any one of claims 1 to 7.
  9. 9. A kit is characterized in that, comprising the nitrocellulose membrane of claim 8.
  10. 10. Use of the nitrocellulose membrane of claim 8 in an immunoassay.

Description

Nitrocellulose membrane, preparation method and application thereof Technical Field The invention relates to the field of immunodetection, in particular to a nitrocellulose membrane, a preparation method and application thereof. Background The initial contact angle of the nitrocellulose membrane is up to 85 degrees due to natural hydrophobicity, the fluctuation range of the chromatography speed is 25% -30%, and the diffusivity and the breakage rate of 35% -40% are easy to appear when streaking is carried out in a low humidity (less than or equal to 30% RH) environment, so that the basic requirements of an immunochromatographic test strip on chromatographic uniformity and streaking stability cannot be met. Limitations of conventional surfactant treatment (for example Tween-20) The effect is poor in timeliness, namely, a nitrocellulose membrane dip-coated by 0.5% Tween-20 has an initial contact angle of about 50 DEG, but after 4 ℃ sealed storage for 1 month, the contact angle is increased to more than 75 ℃ due to migration loss of a surfactant, and the hydrophilicity is basically invalid; The biocompatibility is insufficient, namely, the Tween-20 and a gold-labeled antibody can be subjected to nonspecific adsorption, so that a false positive signal is increased by 15% -20% in the detection process, and the binding rate of the antibody is reduced from the initial 80% to below 65%, so that the detection accuracy is affected; The environmental adaptability is weak, and the chromatographic speed change rate still reaches 20-25% under the humidity fluctuation (40-80% RH) scene, so that the chromatographic speed change device cannot adapt to the use requirements of different regions and different seasons. Core bottleneck for individual plasma processing The hydrophilicity decay is fast, namely, the initial contact angle of the nitrocellulose membrane treated by single argon (power 80W and treatment time 60 seconds) can be reduced to 35 degrees, but the initial contact angle is influenced by the relaxation effect of the surface energy, and the contact angle is increased to more than 60 degrees after the nitrocellulose membrane is stored for 7 days, so that the quality guarantee period requirement of the test strip more than or equal to 6 months can not be met; the surface can be activated only briefly without forming a stable protection layer, and the scribing diffusivity still reaches 20% -25% under the low humidity (25% RH) environment. Intrinsic defects of polyvinylpyrrolidone (PVP) coating alone The adhesive force is poor, namely the surface of the nitrocellulose membrane which is not subjected to plasma pretreatment lacks active binding sites, PVP can be only physically attached, and the falling rate of PVP layer reaches 30% after washing or storing for 1 month; the performance stability is insufficient, after the PVP layer is fallen, the contact angle is raised to more than 70 degrees, the moisture resistance and the hydrophilicity are completely failed (the adhesive tape peeling test shows that the PVP residual rate is only 50 percent); Disclosure of Invention The invention provides a Nitrocellulose (NC) membrane, a preparation method and application thereof, which are used for solving the problems of unstable hydrophilicity, low antibody binding rate, overlarge chromatographic speed change rate, easy falling-off of a polyvinylpyrrolidone layer and high streak diffusivity in a low humidity (less than or equal to 30% RH) environment. In a first aspect, the present invention provides a method of treating a nitrocellulose membrane, comprising: A plasma treatment in which the nitrocellulose membrane is subjected to a plasma treatment, and, Polyvinylpyrrolidone coating, wherein a nitrocellulose membrane subjected to plasma treatment is coated with polyvinylpyrrolidone. In an alternative embodiment, argon and oxygen are used in a volume ratio of 3:1 to 5:1, optionally 4:1, and/or the power is 50 to 100W, and/or the treatment time is 30 to 150 seconds, and/or the vacuum is 10 to 50Pa in the plasma treatment. In an alternative embodiment, a polyvinylpyrrolidone solution having a concentration of 0.3g/100ml to 2.5g/100ml is used in the polyvinylpyrrolidone coating, optionally, a polyvinylpyrrolidone solution having a concentration of 0.3g/100ml to 2.5g/100ml contains a cross-linking agent of 0.025 g/100ml to 0.15 g/100 ml; Still optionally, the solvent in the polyvinylpyrrolidone solution with the concentration of 0.3g/100ml to 2.5g/100ml is deionized water and/or ethanol, and further optionally, the solvent in the polyvinylpyrrolidone solution with the concentration of 0.3g/100ml to 2.5g/100ml is deionized water and ethanol with the volume ratio of 9:1. In an alternative embodiment, the molecular weight of polyvinylpyrrolidone is greater than 1.5 ten thousand and less than 13 ten thousand, optionally the molecular weight of polyvinylpyrrolidone is greater than 3 ten thousand and less than 13 ten thousand, further pre