Sonoporation has been widely accepted as a significant tool for gene delivery as well as some bio-effects like hemolysis, bringing in high demands of looking into its underlying mechanism. A two-dimensional (2D) boundary element method (BEM) model was developed to investigate microbubble-cell interaction, especially the morphological and mechanical characteristics around the close-to-bubble point (CP) on cell membrane. Based on time evolution analysis of sonoporation, detailed information was extracted from the model for analysis, including volume expansion ratio of the bubble, areal expansion ratio of the cell, jet velocity and CP displacement. Parametric studies were carried out, revealing the influence of different ultrasound parameters (i.e., driving frequency and acoustic pressure) and geometrical configurations (i.e., bubble-cell distance and initial bubble radius). This model could become a powerful tool not only for understanding bubble-cell interactions, but also for optimizing the strategy of sonoporation, such that it could be safer and of higher efficiency for biological and medical studies especially in clinics.
This letter proposed advantageous in-uniform gradient cross-section (GCS) channels which weaken the dependence of the coiled-up anechoic metasurface on the total channel length. The privilege of GCS channels was revealed by studying Fabry-Pérot absorbers with designed channel widths. A theoretical framework was set up to explain the inherent sound absorbing mechanism, from which the overall performance as well as dominant working frequencies of linear and exponential GCS channels can be predicted. With proper GCS channel design, the proposed structures were experimentally and theoretically proven to achieve lower absorption frequencies in comparison with conventional uniform cross-section absorbers with the same exterior geometry. Through a parametric study on the near-perfect absorption frequency range of GCS absorbers, the strong tunability brought by GCS was confirmed, suggesting the possibility of on-demand frequency-oriented absorber design. Serving as an approach for acoustic impedance transferring, promising features of GCS can be extensively applied in existing coiled-up anechoic metasurfaces.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.