Therapeutic Ultrasound

Nanobubble-mediated cancer cell sonoporation using low-frequency ultrasound

“…The NB concentrations were calibrated for FITC 4 kDa sonoporation at a fixed pressure of 300 kPa for all tested concentrations. The initial concentration of NBs was 1.29 × 10 7 NBs per μL, and five additional concentrations (2,4,8,12, and 16 times the initial concentration) were tested. The optimal concentration of NBs was found to be 12 times the initial concentration, since higher concentration decreased the uptake.…”

“…The development of intravenously (IV) injected microbubbles (MBs), with an average diameter of 1.5-4 μm, has greatly enhanced the applications of ultrasound (US) beyond soft tissue imaging to functional intravascular imaging, 1 and also to therapeutic applications, as demonstrated with compelling research reporting notable bioeffects. [2][3][4] MBs formed of a gas core and a stabilizing shell are efficient US theranostic probes that serve as both contrast and therapeutic agents. Upon US excitation, MBs cavitate and pulsate volumetrically, applying mechanical forces and transiently forming pores in adjacent cell membranes that can promote local drug and gene delivery.…”

“…13,14 Until recently, the large size of MBs restrained them to intravascular applications, since they were too big to extravasate from the blood vessels into the surrounding tissue. 2,15,16 The development of nanobubbles (NBs) has expanded gasbubble effects beyond the vascular compartment because of their small size (less than 500 nm) that enables effective tumor uptake via the leaky tumor vasculature. [17][18][19] In sonoporation studies, NBs have been employed for the delivery of drugs and genes at high frequencies.…”