Deep-well plate with high nucleic acid extraction rate and preparation method of deep-well plate

Abstract

The invention provides a deep-well plate with a high nucleic acid extraction rate and a preparation method of the deep-well plate. The deep-hole plate with the high nucleic acid extraction rate comprises a containing cavity, and a plurality of deep-hole plate holes are formed in the containing cavity; the deep hole plate skirt edge is fixedly connected to the side edge of the accommodating cavity; the base is formed by extending the bottom of the skirt edge of the deep-hole plate towards the direction far away from the accommodating cavity; wherein an inner corner is arranged on the inner side of the deep hole plate hole. The deep well plate with high nucleic acid extraction rate has the characteristics of good biocompatibility and low nucleic acid adsorption.

Description

technical field [0001] The invention belongs to in vitro diagnostic consumables, and relates to a deep well plate with high nucleic acid extraction rate and a preparation method thereof. Background technique [0002] The most widely used nucleic acid extraction method today is the magnetic bead method. During lysis, the nucleic acid sample is adsorbed by the silicon hydroxyl group on the surface of the magnetic bead to achieve the purpose of separation and purification. The container consumable used in the nucleic acid extraction process is a deep well plate. [0003] In the lysate, under the conditions of a certain concentration of polyethylene glycol solution and the promotion of sodium chloride or magnesium chloride, the molecular conformation of the nucleic acid will change drastically, and a large number of negatively charged phosphate groups on the phosphate skeleton will be exposed. , combined with negatively charged carboxyl groups or silanol groups on the surface of...

AI Technical Summary

Problems solved by technology

[0005] First of all, the most commonly used method for polypropylene modification is blending and melt modification, through the blending of small molecule hydrophilic additives. After thermal processing, the hydrophilic small molecules have poor compatibility with polypropylene materials and will migrate to the surface of the material. , thus enhancing the surface hydrophilicity of polypropylene, but the material is prone to thermal decomposition, yellowing and lower mechanical properties during high-temperature processing; in addition, additives such as antioxidants will also be added

If the polypropylene produced by this method is used to process deep-well plates, it may cause problems: 1. The precipitation of small molecules in the additives during processing and molding. It is found through sample testing that the precipitated small molecules will enter the reagents (such as lysate, cleaning Liquid, magnetic bead suspension, etc.), reduce the surface tension of the lysate, resulting in rapid sedimentation and difficult resuspension of nucleic acid extraction silicon-based magnetic beads, thereby affecting the recovery rate of magnetic beads, that is, reducing the amount of nucleic acid extraction

The principle is that the precipitation of small molecular hydrophilic additives is often an ionic surfactant, and the negative charge on the surface of the magnetic beads will adsorb the positively charged ions in the surfactant, while repelling the negatively charged ions. Therefore, the surface of the magnetic beads The concentration of nearby ions is different from the concentration of the main body in the solution at a certain distance from the surface. The accumulation of counter ions near the surface will shield the surface charge, thus reducing the Zeta potential, and the smaller the absolute value of the Zeta potential, the greater the suspension system. The worse the stability, the more prone to aggregation and sedimentation; 2. Nucleic acid extraction belongs to the field of molecular diagnosis. When the material is melted and blended, the modified factory does not have clean workshop control, and it is easy to introduce impurities such as DNase, RNase, and human DNA. There is a risk of interference in the analysis of diagnostic test results. 3. Auxiliaries pollute the samples. Different brands of auxiliaries cannot guarantee the diversification of biocompatibility when modifying materials. They may react with individual samples and affect the test results. 4. The precipitation of additives has the problem of uneven precipitation in different parts, and the disadvantage that the precipitation changes with time, which cannot guarantee the uniformity of each well, and the difference in the amount of nucleic acid extraction caused by different storage times; 5. Hydrophilic small molecules The precipitation of additives is serious, and the contact angle of pure water on the surface may be as low as about 20 degrees. The magnetic beads in the hanging liquid column are difficult to be adsorbed by the magnet, resulting in the loss of the magnetic beads. The final result is that the recovery rate of the magnetic beads is low and the amount of nucleic acid sample extraction is relatively small.

[0006] The second is the solution of surface coating modification. This method usually uses organic silicon coating, such as silane coupling agent, which also has the problem of pollution into the solution system, and the process is cumbersome, there is a risk of process pollution, and the mass production effect is low. Production high cost

[0007] In the early stage of the present invention, the low-pressure plasma surface grafting scheme was used to replace the blending modification and surface coating scheme, and the hydrophilic monomer was directly grafted to the surface of the formed deep-well plate through plasma treatment, and the hydrophilicity was reflected after modification. Effect, according to the different monomer types of grafting, the contact angle range is about 40-80 degrees, the surface of the deep-well plate after grafting is hydrophilic and there will be no precipitates, low nucleic acid adsorption, slow sedimentation of magnetic beads and easy resuspension, magnetic beads The recovery rate of beads is high, and the amount of nucleic acid is high. However, because this solution introduces monomers and needs to deal with the inner cavity of deep holes, special monomer gas injection ports and electrodes need to be designed according to the product size, which will significantly reduce the processing efficiency, resulting in Production costs are too high

[0008] Directly using polar materials such as PMMA, PS or MBS, because of the high melt viscosity, it is impossible to use the injection molding process to produce complex and thin-walled products such as deep-hole plates, or the material itself is brittle, and the thin-walled products are easily damaged. Production requires special molds and equipment, and the cost is high

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