JPH03224570A - Sterilizing method - Google Patents

Abstract

PURPOSE:To effectively destroy the cells of the bacteria sticking to an object to be sterilized by sealing the object to be sterilized and liquid into a hermetic container and repetitively executing the cycle to rapidly increase the pressure in this hermetic container to a prescribed pressure, then to maintain this pressure for a prescribed period of time and to increase the pressure again after rapidly dropping the pressure. CONSTITUTION:An ultrasonic oscillator 8 is fixed atop a cap body 2 so that ultrasonic oscillations can be applied to water 9 and the object 10 to be sterilized sealed in the hermetic space 3. The pressure in the hermetic space 3 is increased to the pressure within a 1000 to 3000kg/cm<2> range and after this pressure is continued for one minute, the pressure in the hermetic space 3 is rapidly increased and decreased between the atm. pressure and this high pressure for the time of 5 to 10 seconds. Such cycle is executed 30 times. Since the repetitive impacts are applied to the object in such a manner, the cells of the bacterial are effectively destroyed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The sterilization method according to the present invention can be used to sterilize surgical tools such as scalpels and forceps.

(Conventional technology and its problems) Items that are likely to be contaminated with bacteria, such as surgical tools, artificial hearts, and even therapeutic oils and fats, or items that should not be contaminated with bacteria, should be sterilized before use. need to be processed.

For this reason, heat sterilization using high-temperature, high-pressure steam or sterilization using sterilizing gas such as ethylene oxide gas has conventionally been performed.

However, heat sterilization cannot be used when the object to be sterilized is not heat resistant, and sterilization using sterilizing gas does not allow for the presence of trace amounts of residual gas, such as in artificial hearts. It cannot be used if the item is

As another sterilization method, after sealing the object to be sterilized and a liquid such as water in a sealed container, the pressure inside this sealed container is increased to several thousand
A pressurization method is known in which the bacteria attached to the object to be sterilized are sterilized by increasing the pressure to 100 kg/cm''.

However, in the case of conventional autoclaving methods, the pressure inside the sealed container is raised to a predetermined pressure and then allowed to elapse for a predetermined period of time, which requires high pressure and takes a long time. be.

The sterilization method of the present invention eliminates all of these inconveniences.

(Means for solving the problem) In the sterilization method of the present invention, after sealing an object to be sterilized and a liquid in a closed container, the pressure inside the closed container is increased to 1000 to 300.
After rapidly raising the pressure to 0 kg/cI112 and maintaining this pressure for a predetermined period of time, the pressure inside the closed container is rapidly lowered and then raised again. This process is repeated.

(Function) In the case of the sterilization method of the present invention as described above, as shocks are repeatedly applied to the object to be sterilized enclosed in a sealed container together with the liquid, bacterial cells attached to the object to be sterilized are destroyed. Destruction is efficient, with relatively low pressures and relatively short times providing good sterilization.

(Example) Next, an experiment conducted by the present inventor in order to confirm the effects of the present invention will be described.

The experiment was conducted using an apparatus as shown in FIG.

By screwing the lid 2 onto the main body 1, a sealed space 3 can be freely formed between the two members 1.2. A piston 5 is fitted into the cylinder portion 4 provided inside the main body 1.
The other end surface of the rod 6 with one end connected to the above-mentioned closed space 3
is facing.

Both ends of the cylinder section 4 are connected to a hydraulic pressure source 7, and the pressure within the sealed space 3 can be raised or lowered depending on which side of the cylinder section 4 pressure oil is fed by the hydraulic pressure source 7. . Further, an ultrasonic vibrator 8 is fixed to the upper surface of the lid 2 so that ultrasonic vibrations can be applied to the water 9 and the object 1o sealed in the closed space 3.

Using the experimental apparatus configured as described above, Escherichia coli was grown in 1.
lXl0' pieces/! An object to be sterilized was sterilized by sealing a liquid containing a concentration of 11 in a polyethylene bag.

The temperature during sterilization is 15±5℃, and the temperature is 100℃.
0 kg/cm2.1500 kg7cm2.1800
A test was conducted to confirm the sterilization effect under three types of pressure of kg/cm2.

First, in order to carry out the sterilization method of the present invention, the closed space 3
The internal pressure was changed as shown in FIG. That is, 15 seconds after the start of the experiment, the pressure inside the closed space 3 is increased to a predetermined pressure, this pressure is continued for 1 minute, and then the pressure inside the closed space 3 is lowered between atmospheric pressure and the pressure within 5 to 10 seconds. It was raised and lowered rapidly. After performing such a cycle 30 times, the number of E. coli contained in the object to be sterilized was measured, and this number was found to be the same as the pressure in the closed space 3 (1000 kg/cm2.1500
kg/c (2 types)), it changed as shown by the broken line a in Fig. 3.

On the other hand, after 30 minutes had elapsed while keeping the pressure in the sealed space 3 constant as shown in Figure 4, the number of E. coli contained in the objects to be sterilized after processing was measured. Pressure in space 3 (1000 kg/cm2.1500 k
g/cm', 1800 kg/c Otori 2), it changed as shown by the solid line in Fig. 3.

As is clear from FIG. 3, according to the sterilization method of the present invention, when the pressure and time are the same, a better sterilization effect can be obtained. It is possible to lower the amount or shorten the time.

(Effects of the Invention) As described above, the sterilization method of the present invention can reduce the pressure or time necessary to obtain the desired sterilization effect, so it is relatively low cost. This enables efficient sterilization.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the state of pressure change when carrying out the sterilization method of the present invention, Fig. 2 is a cross-sectional view of the experimental equipment, Fig. 3 is a diagram showing the experimental results, and Fig. 4 is a diagram showing the conventional method. FIG. 1: Main body, 2: M body, 3: Closed space, 4 Niji cylinder part,
5: piston, 6 rods, 7: hydraulic power source, 8: ultrasonic vibrator, 9: water, 10: object to be sterilized.

Claims (2)

[Claims] (1) After sealing the object to be sterilized and the liquid in a sealed container, the pressure inside this sealed container is set to 1000 to 3000 kg/cm^
A sterilization method that involves repeatedly raising the pressure to 2, maintaining this pressure for a predetermined period of time, rapidly lowering the pressure inside the closed container, and then raising it again. (2) Pressure inside the sealed container is 1000 to 3000 kg/c
2. The sterilization method according to claim 1, wherein ultrasonic vibration is applied to the liquid in the sealed container and the object to be sterilized while maintaining the temperature at m^2.