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Real Time Electronic Feedback for Improved Acoustic Trapping of Micron-Scale Particles

NCJ Number
Date Published
1 page

Since previous work has demonstrated successful, automated adjustment of acoustic frequency to account for changes in temperature and buffer properties in various samples, the current study indicated that during acoustic trapping, real-time monitoring of voltage measurements across the piezoelectric transducer correlates with sample-dependent changes in the medium.


Acoustic differential extraction has been previously reported as a viable alternative to the repetitive manual pipetting and centrifugation steps for isolating sperm cells from female epithelial cells in sexual assault sample evidence; however, the efficiency of sperm cell isolation can be compromised in samples that contain an extremely large number of epithelial cells. When highly concentrated samples are lysed, changes to the physicochemical nature of the medium surrounding the cells impacts the acoustic frequency needed for optimal trapping. The results of the current project were achieved with a wideband peak detector circuit, which identifies the resonant frequency with minimal disruption to the applied voltage. This study further demonstrated that immediate, corresponding adjustments to acoustic trapping frequency provides retention of sperm cells from high epithelial cell-containing mock sexual assault samples. (publisher abstract modified)

Date Published: January 1, 2019