The nucleic acid test (PCR TEST) uses a flocked swab instead of a cotton swab.
Flocking is a craft, not a material
Flocking is not the fluff of any plant, but a very common fabric treatment process.
Widely used in the textile industry, automobile manufacturing, printing industry, chemical industry and other fields.
The flocking process means vertical fixing of some cut or milled short fibres to some kind of adhesive-coated surface. Short fibres are usually nylon, polyester, or other artificial fibers. The range of planting them is very wide, and surfaces such as cloth, plastic, wood, leather, paper, etc. can be flocked.
Flocking only needs three things, 1, short fibers; 2, adhesive, 3, some kind of surface
Flocking is very common in everyone’s life, just usually without realizing it. For example, flocking fabrics can be found on clothes, curtains, carpets, and furniture. Usually, those surfaces that are fluffy and comfortable to the touch are brought by the flocking process.
In addition to the decorative effect, the flocking technology has also been tried by scientists to make graphene lithium battery anode sheets; make special lipophilic and hydrophobic materials to absorb marine oil spills, etc.
The principle of flocking
At present, the most commonly used flocking method is electrostatic flocking. After the fluff enters the high-voltage electric field, it contacts the negative electrode and is negatively charged.
Don’t worry if some fibers fall to the side and don’t stick to the side. After they touch the positive electrode side, the negative charges on the surface are completely neutralized, and they will fall to the negative end due to the force of the electrostatic electric field. Repeat the above movement until they are all stuck.
Flocked swabs for nucleic acid testing
The flocking swabs used for nucleic acid detection are mostly “planted” with nylon short fibers. The reason for choosing flocked nylon over cotton swabs is the functional need for sampling.
Flocked swab
Any material design is purposeful, and flocked swabs for nucleic acid detection need to meet the following characteristics:
② After the swab is put into the preservation solution, it has to “let go” to release the biological sample, and it cannot hold the sample firmly for a second or divide it. ③ It cannot react with biological samples and destroy the samples.
Because cotton itself has superior hydrophilicity and adsorption, once it comes into contact with the sample, it is like the characters in Qiongyao play. In contrast, nylon flocked swabs are like a scumbag “can take it and put it down.
Therefore, the collection and release volume of nylon flocking swabs is much larger than that of traditional winding cotton swabs. Experimental studies have shown that the collection and release volume of flocking swabs can reach 95% of the samples, while cotton swabs are only about 20%.
In fact, the ability of cotton swabs to grasp the sample is not bad, but after inserting the preservation solution, the flocked swab can quickly let go of the sample to be eluted, but the cotton swab will make the cells stuck in the fiber mass and cannot be separated.
Otherwise, the nucleic acid will be degraded before the detection begins, and the correct result will definitely not be detected.
Because of this, it is superfluous to worry that nylon is a synthetic fiber that is harmful to the human body. Flocked fibers have even been tried in regenerative medicine to help repair damaged bones and cartilage. By implanting the flocked fibrous scaffold, the properties of the extracellular matrix are modeled, allowing stem cells to adhere to it to proliferate and differentiate; and provide sufficient space for the newly synthesized matrix and capillaries to enter.