Destruction of Recombinant Tissue Plasminogen Activator (Rtpa) -Loaded Echogenic Liposomes Under Dual Frequency Sonication



Mobasheri M¹ ; Mokhtaridizaji M¹ ; Toliyat T² ; Mehrpour M³
Source: Journal of Kerman University of Medical Sciences Published:2018

Abstract

Background: Echogeiiic liposomes (ELIPs) encapsulate chugs and gas bubbles within lipid vesicles. The destruction of ELIPs in response to MHz and kHz ultrasound waves lias been studied previously. Applying ultrasound above a certain threshold causes encapsulated gas bubbles destruct rapidly by fragmentation or more slowly by acoustically driven diffusion. Tliis study compares the destruction of recombinant tissue plasminogen activator (ltPA) -loaded echogenic liposomes using three frequency protocols: 130 kHz. 1 MHz and dual (130 kHz +1 MHz). Method: hi gel phantom ELIPs were imaged by diagnostic ultrasound system and simultaneously destructive ultrasonic fields were applied at different intensities in each protocol. Images were analyzed. Results: According to the results. 80% decline in MGV (mean of gray value) relative to initial MGV was associated with ELIPs fragmentation. At 130 kHz. results showed an 80% decline in MGV mid fragmentation happened at all applied ultrasound intensities (0.01 W/cm as fragmentation threshold), hi MHz and dual protocols, on average, less than 50% decline in MGV was observed which indicated an acoustically driven diffusion. Conclusion: Our study shows that kHz protocol fragments ELIPs more effectively than other two protocols. For better results, dual frequency protocols need optimized combination of frequencies and phases. © 2018, Kerman University of Medical Scienc. All rights reserved.