PCR扩增产物污染：这是PCR反应中最常见的污染问题。因为PCR产物的

PCR扩增产物污染：这是PCR反应中最常见的污染问题。因为PCR产物的拷贝量远高于PCR检测数拷贝的极限，所以极微量的PCR产物污染也会实验结果假阳性。最可能造成PCR产物污染的形式是气溶胶污染，在空气与液体面摩擦时会形成气溶胶，在操作时比较剧烈地摇动反应管，开盖时、吸样时都可以形成气溶胶而引起污染。根据计算，一个气溶胶颗粒可以含有48000个拷贝，因此由其造成的污染是一个值得特别重视的问题。4.实验室中克隆质粒的污染：在分子生物学实验室以及某些用克隆质粒做阳性对照的检验室，这个问题也比较常见，因为克隆质粒在单位容积内含量相当高，另外在纯化过程中需要用较多的用具及试剂，而且活细胞内的质粒，由于活细胞的生长繁殖的简便性以及其具有很强的生命力，引起污染的可能性也很大。

Contamination of PCR amplification products: This is the most common contamination problem in PCR reaction. Because the copy amount of PCR products is much higher than the limit of the number of copies detected by PCR, a very small amount of PCR product contamination will also lead to false positive results. The most likely form of PCR product pollution is aerosol pollution. Aerosol will be formed when the air rubs with the liquid surface. When the reaction tube is shaken violently during operation, aerosol can be formed during cover opening and sample suction. According to the calculation, an aerosol particle can contain 48000 copies, so the pollution caused by it is a problem worthy of special attention. 4. Pollution of cloned plasmids in laboratories: this problem is also common in molecular biology laboratories and some laboratories that use cloned plasmids as positive control, because the content of cloned plasmids in unit volume is quite high. In addition, more tools and reagents are needed in the purification process, and the plasmids in living cells have strong vitality due to the simplicity of growth and reproduction of living cells, The possibility of causing pollution is also great.

PCR product contamination: This is the most common contamination problem in PCR reaction. Because the number of copies of PCR products is much higher than the limit of the number of copies detected by PCR, a very small amount of PCR products will cause false positive results. The most likely form of PCR product pollution is aerosol pollution. Aerosol will be formed when the air rubs against the liquid surface. When the reaction tube is shaken violently during operation, aerosol can be formed when the cover is opened and the sample is sucked, causing pollution. According to the calculation, an aerosol particle can contain 48,000 copies, so the pollution caused by it is a problem that deserves special attention. 4. Contamination of cloned plasmids in laboratories: This problem is also common in molecular biology laboratories and some laboratories where cloned plasmids are used as positive controls, because the content of cloned plasmids in unit volume is quite high, and in addition, more tools and reagents are needed in the purification process. Moreover, plasmids in living cells are likely to cause contamination due to their simplicity of growth and reproduction and their strong vitality.