Ten antibacterial testing methods, there is always one suitable for your fabric testing

Among the many ways of bacterial transmission, fabrics are one of the main carriers. Because they are porous and loose, they can easily absorb various impurities and become carriers of reproductive and parasitic bacteria. The presence of these bacteria not only makes fabrics contaminated , damage, and more importantly, it increases the cross-infection rate in the public environment, affecting human health. With the continuous improvement of people’s living standards, people pay more and more attention to the requirements of health standards, so antibacterial fabrics have attracted more and more attention.

1. Parallel line drawing method (stripe method):

This test method is a simple and fast qualitative test method, suitable for water washing resistance and The principle of testing the antibacterial properties of dry-cleaning resistant antibacterial finishing fabrics is as follows: inoculate the bacterial solution on the agar medium by drawing parallel lines, stick the sample on the agar surface, and incubate it for a period of time under certain conditions. , check the clean area that appears along the scratched area on the agar surface due to the interruption of bacterial reproduction, grade the antibacterial activity, and evaluate the antibacterial ability of the fabric.

2. Antibacterial ring test method (halo method):

Inoculate the test bacteria on the surface of the agar medium plate, and then put the test sample on it. Since the bacteriostatic agent continues to It dissolves and spreads in agar to form an inhibitory ring, and the antibacterial ability is evaluated by measuring the width of the inhibitory ring.

3. Test standard AATCC 100

This test method is a quantitative test method proposed by the American AATCC committee. It is used to detect the bactericidal and bacteriostatic abilities of fabrics. It is currently the The relatively famous antibacterial performance testing method abroad is also the origin of some new methods at home and abroad. The principle of this method is: after the fabric comparison sample and the sample are inoculated with bacteria and cultured under certain conditions, a neutralizing solution is added to elute the bacteria, and the concentration of the bacterial solution in the eluate is measured using the dilution plate method to determine the viable bacteria. Cultivate and count, obtain the bacterial reduction percentage of the antibacterial fabric, and evaluate the antibacterial and bactericidal performance of the fabric.

4. Oscillating flask method:

The oscillating flask method imitates the wearing conditions of the human body, allowing bacteria to contact the bacteriostatic agent in the fabric under oscillating conditions (300r/min), and oscillate After 1-6 hours, count the bacteria through culture and calculate the percentage of bacterial reduction to determine the antibacterial performance.

When applying this test method, the tested sample is not limited by the shape of the fabric. This method is not only applicable to general fabrics, but also to uneven fabrics, fabrics with hair or feathers, and Powdered fabrics, etc., have a wide range of uses. It can also be applied to antibacterial products such as antibacterial plastics and antibacterial tiles. Water-repellent materials such as plastics should be pelletized before testing.

5. Test standard FZ/T 01021-92

This method is the domestic fabric industry standard based on the American AATCC100-1981. A quantitative test method for bacterial performance. The basic principle is: inoculate the test bacteria on the fabric (comparison sample and sample), and after “0” contact time culture and certain time culture, the sample is eluted, and then the viable bacteria are counted in the eluate. Calculate the percent bacterial reduction of the sample. This method has particularly detailed provisions on the determination of the number of colonies on a plate during culture counting of viable bacteria. However, in this standard, after culturing for a certain period of time, it is eluted with 100 ml of buffer and shaken vigorously for 1 minute. This process has yet to be explored, because vigorous shaking is required. It may cause the growth or decrease of bacteria, which will affect the test results.

6. Test standard JIS L 1902 1998

This method is Japan’s industrial standard, which stipulates the qualitative test method (halo method) and the quantitative test method (immersion method). Among them, the qualitative test method can only test whether it has antibacterial performance, but cannot accurately measure the antibacterial rate. But this method is particularly simple and easy to operate. The principle is to place the sample in the center of the flat culture medium. After a period of incubation, observe the antibacterial ring generated around the sample, calculate the width of the inhibitory ring, and evaluate whether the sample has antibacterial ability. At the same time, it is also very simple to judge the validity of the test. Just watch whether there is bacterial proliferation in the untreated sample after culture. This method also specifies the requirements for the sample in detail, including fabrics, yarns, soft fillers, long pile, etc.

The principle of the quantitative test method (impregnation method) is also to inoculate the sample with bacteria and culture it, then count the viable bacteria after contact culture at “0” time and culture at a certain time, and calculate the antibacterial activity value and sterilization value. activity value. The characteristics of this method are:

1-1. Different from other methods that use turbidimetric tube to measure the concentration of bacterial liquid roughly, it is determined by measuring the absorption rate with a complete meter. The concentration of bacterial solution improves the accuracy of the test.

1-2. Use frozen physiological saline (0.85%) to elute the cultured sample to avoid bacterial growth or decrease during the elution process, ensure the accuracy of the required bacterial count, and reduce testing error.

1-3. When calculating the results, the antibacterial activity value and bactericidal activity value should be used to comprehensively express the antibacterial and bactericidal ability of the sample, and the logarithmic value should be used to reflect the test results.

7. Test standard JIS L 1902 2002

This standard is a test method further modified based on the JIS L 1902 1998 test method. This method also introduces two There are three test methods, qualitative test method and quantitative test method, but two quantitative test methods are introduced, namely bacterial liquid extraction method and bacterial test method.This method, its qualitative method (bacterial inhibition ring method) and bacterial liquid extraction method are basically the same as the principles and methods in the JIS L 1902 1998 standard. The principle of its bacterial inoculation method is to inoculate bacteria into a humidified environment under pressurized conditions. On the test piece, it is then incubated for a period of time under a certain humidity, and then the sample is eluted, viable bacteria are counted, and the bacterial reduction value is obtained.

This method provides detailed regulations on the test bacteria for different test purposes and uses and different treatments of fabrics. It also introduces the bacterial liquid extraction method for determining the sterilization activity value of fabrics, using the bacterial inoculation method, Calculate bacterial reduction value.

8. Antifungal test standard JIS Z 2911

This method is a test method developed for fungi. Its basic principle is: uniformly spread on the sample and culture medium Spray a certain amount of mixed spore suspension, and after cultivating for a certain period of time, observe the mold growth on the sample, and conduct a graded qualitative evaluation of the antifungal performance.

9. QUINN TEST:

This method is QUINN’s fabric antibacterial performance testing method. The basic principle of this method is The principle is to inoculate the test bacterial solution on the fabric, then cover it with a semi-solid agar medium, and after culturing it for a period of time under certain conditions, observe the number of colonies on the fabric and calculate the antibacterial rate. This method is also a quantitative test method for testing the antibacterial ability of upper fabrics. It is simple, convenient and widely used.

10. Improved QUINN test method:

Professor Zou Chengshu, a well-known microbiology expert at Qingdao Medical College (an important partner of the author), began to improve the QUINN TEST in the early 1980s. Later, through the joint efforts of the domestic medical community, the Chinese version of QUINN TEST – the improved Quin test method was completed. This method is modified on the basis of Quinn’s test method. The principle is to inoculate the test bacterial solution on the fabric, cover it with culture medium, and after incubation for a certain period of time, observe and count the number of colonies on the antibacterial and non-antibacterial fabrics. , calculate the antibacterial rate, and quantitatively test the antibacterial performance of antibacterial fabrics. This method is a simple, fast and reproducible quantitative test method. Compared with the original Quin test method, it has the following advantages:

2-1. Several different fabric pairs can be tested at one time The antibacterial properties of the same bacteria improve testing efficiency and save time.

2-2. The concentration of the inoculated bacterial solution is small (6000/ml), the nutrients are sufficient, and the colonies become larger. It is easy to directly observe the growth of the colonies with the naked eye, avoiding contamination caused by viewing with a microscope.

2-3. Use physiological saline instead of broth to dilute the bacterial solution to avoid bacterial growth during the dilution process and affect the accuracy of the test.

2-4. The process of drying the fabric under a certain relative humidity after adding bacterial solution is omitted, which simplifies the experimental steps and avoids the death of bacteria due to inaccurate temperature control during the drying process. Disadvantages.

However, there are also some shortcomings in this method:

In this method, in the step of covering the agar medium, in order to avoid the medium from overflowing outside the sample, the sample after adding the bacterial solution Put the plate in the refrigerator for 15 minutes. There is no specific temperature specified. Unsuitable temperature will cause the death or growth of bacteria. Generally, 5-10°C can ensure that bacteria will not die or grow, but there is no provision in this method. This will affect the test results during the movement of the sample.

Chemical has been focusing on the R&D and sales of functional fabric finishing for 10 years. It adheres to the brand cooperation strategy and can provide free technical solutions to functional fabric finishing problems. Unified service hotline: 400-0909-770

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