Bacterial infections persist to be a serious public health challenge, and effective techniques for their inactivation are essential. Effective sonic inactivation of bacteria like E. coli relies on identifying their resonant frequencies. However, traditional methods of discovering these frequencies through laborious physical experimentation can be time-consuming and costly. This article proposes a novel method for determining the resonant frequency of E. coli using a specially designed tensegrity model that incorporates spectral element formulation. The model, which conforms to the shape of E. coli, allows for the calculation of resonant frequencies without the need for time-consuming element sensitivity simulations. To overcome issues related to rigid body motion, a small incremental operation is employed to calculate the system determinant. The resonant frequencies obtained from the model are found to be in excellent agreement with available experimental results. Additionally, the model reveals that changes in E. coli geometry have a significant impact on inactivation frequency, while other parameters such as density are less influential. The proposed tensegrity model is a powerful technique that can provide rapid and accurate identification of resonant frequencies, making bacterial inactivation instantaneous and more effective, particularly during times of health crises