Evaluation of Germicidal efficacy of Novel DeepUltraviolet (DUV) irradiation on various pathogens and biofilms

Abstract

Pathogens have emerged to become more virulent and common. This is evident as seen in the Covid-19 pandemic that happened in December 2019. Ultraviolet (UV) means of disinfection have been emerging as a promising source used to help combat these pathogens. The need for new emerging sources of UV disinfection stems from the eventual phasing out of conventional mercury lamps. LUMINOUS! NTU (Nanyang Technological University) has developed a novel DUV chip that can be used for germicidal disinfection. The DUV chip can emit UV radiation at the wavelength of 265 nm. This work will investigate the DUV chip’s germicidal efficacy on bacteria E. Coli (TOP 10 PTA-10989) through germicidal experiments. Results collected show that after DUV irradiation, we were able to achieve a 2.5 log reduction in bacteria within 3 minutes of irradiation time. In addition, using theoretical analysis, we demonstrated that the optimal irradiation for disinfection is 3-5 cm.