Construction of aseptic operating environment in cell culture laboratory

First, cell culture and laboratory description

Tissue culture simulates the physiological environment in vitro, and allows tissues taken out from the body to survive, grow, and pass under sterile, appropriate temperature and certain nutrient conditions, and maintain the original structural and functional characteristics.

By cell culture is meant the growth of cells including individual cells under in vitro conditions.

The main difference between tissue cell culture technology and other general laboratory work is the requirement to maintain aseptic operation and avoid the effects of microorganisms and other harmful factors. At present, the extensive use of ultra-clean benches greatly facilitates tissue cell culture work and makes it possible for some routine laboratories to perform cell culture.

Cell culture laboratories should be able to perform six tasks: aseptic processing, incubation, preparation, cleaning, sterilization, and storage.

Second, the construction of the aseptic operating environment in the cell culture laboratory

1 , aseptic operation room

The sterile operating area is limited to areas of cell culture and other aseptic operations, and is preferably isolated from the outside world and cannot be walked through or otherwise interfered with.

The ideal aseptic operating room should be divided into three parts:

a) Dressing room - for changing clothes, shoes and wearing hats and masks.

b) Buffer room – located between the dressing room and the operating room, in order to ensure a sterile environment in the operating room, and to place a constant temperature incubator and some necessary small instruments.

c) Sterile operation room - dedicated to aseptic processing, cell culture. The size should be appropriate, and the top should not be too high (not more than 2.5m) to ensure the effective sterilization effect of ultraviolet rays; the wall is smooth and has no dead ends for cleaning and disinfection.

The workbench should not be placed against the wall. The countertop should be smooth pressed and molded into a surface, painted white or gray to facilitate the observation of the anatomical structure and phenol red.

Air disinfection in aseptic operation room: UV lamp - produces ozone, and the room temperature and humidity are high, which is not conducive to the health of workers.

Air-filtered constant temperature and humidity device - best.

Clean room (zone) air cleanliness level table cleanliness level:

The maximum allowable number of dust particles / cubic meter 100 level 3,500 0 5 110000 level

The maximum allowable number of microorganisms is 350,000 2,000 100 3100000

Floating bacteria / cubic meters 3,500,000 20,000 50010300000

Settling bacteria / dish 10,350,000 60,000 - 15

Ozone-free UV sterilizer electronic disinfection sterilizer--Under the action of high-voltage electric field, the internal and external electrodes of the electron tube undergo strong electron bombardment, which ionizes the air and converts the oxygen in the air into ozone. Ozone is a strong oxidant, which can react with the bacterial membrane and the enzyme protein hydrogen sulfide to oxidize and decompose, so that the ozone gas diffuses diffusely to achieve the purpose of sterilization, and there is no dead angle when disinfecting. The residual ozone in the space after disinfection can be reduced to oxygen by itself for 30-40 minutes, the air does not leave odor, and the surface of the disinfected object is not left with residual poison.

2 , purification workbench

The operation is simple, the installation is convenient, the occupied space is small, and the purification effect is good.

There are two main types of purification workbench used in general bacterial culture rooms:

a) side flow or vertical

b) Outflow or horizontal laminar flow.

The working principle of the purification workbench is roughly the same. Usually, the indoor air is filtered through the coarse filter, and the centrifugal fan is pressed into the static pressure box, and then filtered by the high-efficiency air filter, so that the clean air flow sent out has a uniform uniform section. The wind speed passes through the sterile field to create a dust-free, sterile, high-clean work environment.

Side-flow workbench: The airflow after air purification flows from the left or right side through the work surface to the opposite side, and also from the top to the bottom or from the bottom to the opposite side, forming an airflow barrier to keep the working area sterile. The workbench structure is closed.

Outflow (horizontal) workbench: The purified air flows toward the operator, so the external airflow is not mixed into the operation, but the hazardous substance test operation is disadvantageous to the operator.