Everyone knows that there are many labs, so how many people know about PCR labs? And what are the basic requirements for designing PCR labs? Then there will be VOLAB Xiaobian to discuss with everyone~
1, PCR laboratory layout
The PCR amplification test laboratory is in principle divided into four separate work areas: reagent storage and preparation area, sample preparation area, amplification reaction mixture preparation and amplification area, and amplification product analysis area. In order to avoid cross-contamination, entering each working area must strictly follow a single direction, that is, only from the reagent storage and preparation area → specimen preparation area → amplification reaction mixture preparation and amplification area → amplification product analysis area. Reagent and sample transfer between each experimental zone should be performed through a transfer window.
2. Laboratory Air Conditioning Ventilation System Design and Pressure Control
PCR laboratories do not have strict purification requirements, but in order to avoid the possibility of cross-contamination between the various experimental areas, it is advisable to use a full-flow air distribution system. At the same time, the proportion of sending and exhausting should be strictly controlled to ensure the pressure requirements of each experimental area.
2.1, specimen preparation area
The main operations in this area are the preservation of samples, the extraction of nucleic acids (RNA, DNA), storage and their addition to amplification reaction tubes and the determination of DNA synthesis. The pressure gradient requirements in this area are: positive pressure relative to the adjacent area to avoid aerosol contamination from the adjacent area into this area. In addition, due to the possibility of aerosol-induced contamination during the loading operation, unnecessary walking in the area should be avoided.
2.2. Reagent storage and preparation area
The main operations in this experimental area are the preparation of storage reagents, the dispensing of reagents, and the preparation of main reaction mixtures. Reagents and materials used for sample preparation should be shipped directly to this area and must not pass through other areas. Reagent raw materials must be stored in this area and prepared in the area into the required storage reagents. There are no strict requirements for the control of air pressure.
2.3, amplification product analysis area
The main operation in this area is the determination of amplified fragments. This area is the main source of contamination of the amplified product. Therefore, the pressure gradient requirements for this area are: Negative pressure relative to the adjacent area to avoid diffusion of amplified products from the area to other areas.
2.4, amplification reaction mixture preparation and amplification zone
The main operation in this area is DNA amplification. In addition, the addition of the prepared DNA template (from the sample preparation area) and the main reaction mixture (from the reagent storage and preparation area) to prepare a reaction mixture, etc. can also be carried out in this area. The pressure gradient requirements in this area are: negative pressure relative to the adjacent area to avoid aerosol leakage from the area. In order to avoid the pollution caused by aerosols, unnecessary walking in the area should be minimized. Individual operations such as sampling should be performed in the clean bench.
3.1. Strict division of work area
(1) The setting of each experimental area is reasonable;
(2) Each experimental area should have obvious marks (such as striking house numbers or different ground colors, etc.) to avoid confusion between equipment items and reagents in different experimental areas.
3.2, reasonable system settings
(1) Reasonable air-conditioning ventilation system setting, try to use the full-send air-conditioning system;
(2) Strict airflow pressure control ensures different pressure requirements in different experimental areas.
3.3, the standard operation
(1) The technicians of the amplification inspection laboratory must perform on-the-job training and can only engage in clinical gene amplification tests after passing the training;
(2) During the experimental operation, the operator must wear gloves and replace them frequently. In addition, the use of disposable caps during operation is also an effective measure to prevent contamination;
(3) The cleaning work is timely and correct. After the experiment is finished, the area must be cleaned immediately. In addition to the conventional disinfecting liquids for the disinfection of surfaces or the irradiation and disinfection of ultraviolet lamps, some experimental equipment should also be subjected to high pressure sterilization.
3.4, strict management
(1) Strictly control the personnel entering and leaving the laboratory. Persons unrelated to the experiment shall not enter or leave the laboratory at will, and if necessary, they shall set up independent passages and doors to and from the entire experimental area.
(2) Minimize unnecessary walking in the experimental area to reduce the possibility of cross-contamination.
(3) The amplified product analysis area is the most important source of contamination of the amplified product. The waste solution cannot be dumped in the laboratory. It must be soaked in the disinfectant solution and then discarded in a place away from the laboratory. The used tips are disposable. The materials should also be disinfected and sterilized and then uniformly treated, such as incineration;
(4) The amplification product analysis area may use certain gene mutations and toxic substances, and special attention should be paid to the safety protection of the experimenter.
3.5. Complete laboratory facilities
Complete laboratory supporting facilities are necessary conditions for ensuring the experimental work. The corresponding equipment and instruments should be equipped according to the different experimental contents of each laboratory, such as ultra-clean benches, centrifuges, and sample feeders.