Is UVC Light Effective for Bacteria and Virus?

How effective is UV sterilization? Is it effective against bacteria and viruses? What are the advantages and disadvantages? These are the questions I often hear in the field of microbiology, especially when people think about how dirty their phones are. As more and more UV germicidal products are put on the market, you may wonder if they are worth trying. So, let's delve into it! 

Ultraviolet rays have been used for sterilization and disinfection as early as the middle of the 20th century. With the advancement of technology, especially the development of UV bulbs themselves, their reliable long life (thousands of hours) and smaller size (for example, UV LEDs compared with traditional UV bulbs) have expanded their use range. You will find it can be used to disinfect: water, air, fruits, vegetables, surgical appliances, tablets, toys and various surfaces.

When it comes to ultraviolet sterilization, not all types of ultraviolet rays are effective. what does that mean? In order to obtain some technical information, ultraviolet (UV) means "beyond violet light" and refers to a series of electromagnetic waves whose wavelength (shorter than the violet light of visible light) (higher frequency and energy). There are three types of ultraviolet rays, which have reduced wavelength and increased energy. They are UVA, UVB and UVC. For ultraviolet sterilization, only ultraviolet rays (100-280nm), such as 265~278 uvc rays and 222nm far uvc rays, have enough energy to effectively kill microorganisms. When you buy ultraviolet germicidal products to try in your home or business, please make sure that the ultraviolet wavelength is within the range of UVC (100-280 nm). Is UV sterilization effective against viruses and bacteria? The short answer is yes, there are even more creatures. Studies have shown that UVC at 254 nm is effective against all food-borne pathogens, natural microbiota, molds and yeasts. Because the size and shape of microorganisms are different, they will affect their UV absorption, so the time required to kill each species will be different.

Of course, each sterilization method has its advantages and disadvantages.

Another limitation of UV sterilization is that UVC causes so much damage to protein and DNA/RNA that they cannot be used in biomedical products. For example, UVC sterilization of viruses can cause so much damage to the surface proteins of the viruses that they cannot be used as vaccines to induce an appropriate immune response. Another "ultraviolet inactivation" method is used in biomedical products to retain virus surface proteins while effectively inactivating the virus. This is also the method we use to purify virus products for UV inactivation, because we hope to use the complete virus protein of the UV-treated virus for biomedical purposes, such as the production of antibodies. Finally, whether you are looking for a robot to disinfect counters, a magic wand to wave on rough hotel sheets, or a gizmo for disinfecting stinky shoes, UV sterilization is a good choice. Remember, it is important to follow the manufacturer's instructions regarding light source distance, exposure time, and safety precautions for any equipment purchased.