Different biological effects of exposure to far-UVC (222 nm) and near-UVC (254 nm) irradiation

Assessing the safety of new germicidal far-UVC technologies

The COVID-19 pandemic underscored the crucial importance of enhanced indoor air quality control measures to mitigate the spread of respiratory pathogens. Far-UVC is a type of germicidal ultraviolet technology, with wavelengths between 200 and 235 nm, that has emerged as a highly promising approach for indoor air disinfection. Due to its enhanced safety compared to conventional 254 nm upper-room germicidal systems, far-UVC allows for whole-room direct exposure of occupied spaces, potentially offering greater efficacy, since the total room air is constantly treated. While current evidence supports using far-UVC systems within existing guidelines, understanding the upper safety limit is critical to maximizing its effectiveness, particularly for the acute phase of a pandemic or epidemic when greater protection may be needed. This review article summarizes the substantial present knowledge on far-UVC safety regarding skin and eye exposure and highlights research priorities to discern the maximum exposure levels that avoid adverse effects. We advocate for comprehensive safety studies that explore potential mechanisms of harm, generate action spectra for crucial biological effects and conduct high-dose, long-term exposure trials. Such rigorous scientific investigation will be key to determining safe and effective levels for far-UVC deployment in indoor environments, contributing significantly to future pandemic preparedness and response.

Understanding the charismatic potential of nanotechnology to treat skin carcinoma

Carcinoma is a condition that continues to pose a significant challenge, despite current medical advances. Skin carcinoma is the leading cause of cancer, and it has seen a massive increase all over the world. The challenges with current treatment are due to toxicity that leads to many more skin complications. Due to this to avoid such complications by designing diverse nanoparticles as delivery carriers, nanomedicine is employed as a hub for diagnostics and therapy. Liposomes, gold nanoparticles, transferases, nanofibers, etc., can all be used as delivery nanocarriers. These nanoparticles' structures and characteristics protect the medicine from degradation and improve its stability. Surface modifying agents and procedures are employed to functionalize nanoparticles, resulting in smart delivery systems. The application of nanotechnology-based approaches systematically increases drug delivery to target cells. Skin cancer has several challenges, including a long time to diagnose early types of cancer and a slower growth rate. This review focuses on innovative skin cancer therapy techniques, focusing on nanotechnology and the challenges associated with current treatment of skin cancer.

Impacts of Surface Characteristics and Dew Point on the Blue-Light (BL405) Inactivation of Viruses

The increased prevalence of multidrug-resistant organisms (MDROs), healthcare associated infections (HAIs), and the recent COVID-19 pandemic has caused the photoinactivation industry to explore alternative wavelengths. Blue light (BL405) has gained significant interest as it is much less harmful to the skin and eyes than traditional germicidal wavelengths; therefore, in theory, it can be used continuously with human exposure. At present, the viricidal effects of BL405 are largely unknown as the literature predominately addresses bacterial disinfection performed with this wavelength. This work provides novel findings to the industry, reporting on the virucidal effects of BL405 on surfaces. This research utilizes three surfaces: ceramic, PTFE, and stainless steel. The efficacy of BL405 inactivation varied by surface type, which was due to surface characteristics, such as the contact angle, porosity, zeta potential, and reflectivity. Additionally, the effect of the dew point on BL405 inactivation efficacy was determined. This research is the first to study the effects of the dew point on the virucidal effectiveness of BL405 surface inactivation. The effects of the dew point were significant for all surfaces and the control experiments. The high-dew-point conditions (18 °C) yielded higher levels of BL405 inactivation and viral degradation for the experiments and controls, respectively.