Generalized single-degree-of-freedom model to study viral inactivation by radiated microwaves

Objective: Recent outbreaks and pandemics have emphasized the need for safe and reliable viral inactivation methods. The purpose of this work is to develop a simple and effective modeling approach to investigate viral inactivation via microwave absorption mediated by dipolar coupling. Methods: Leveraging established techniques from the dynamic analysis of structures, a generalized Single-Degree-Of-Freedom (SDOF) model is developed, which is fully consistent with the dipolar resonance mode. Results: The model can reproduce the main features of dipolar coupling with minimal computational time. Moreover, it allows mimicking the broadening of the resonance range associated with heterogeneous virus size, via Monte Carlo simulations, as well as water induced damping. Conclusion: The results support the potential role of dipolar coupling for viral inactivation by microwave irradiation in the GHz range. The model can be used to assist in the interpretation of the experimental results, leading to an optimization of the inactivation protocols. Significance: The proposed approach is versatile and can be extended to describe more complex cases, such as non-spherical geometries and/or non-homogeneous material properties.