Tailoring the size of ultrasound responsive lipid-shelled nanodroplets by varying production parameters and environmental conditions

• Increasing the volumetric concentration of PFP led to an increase in size lipid-coated NDs. sonication intensity and time a decrease ND size. The coating layer can be labelled with lipophilic fluorophores without affecting overall NDs were stable at 4 °C for one week, 37 110 min. Ultrasound (0.5 MHz, 2–4 MPa) caused vaporisation within tissue-mimicking phantom. Liquid perfluorocarbon nanodroplets (NDs) are attractive alternative microbubbles (MBs) ultrasound-mediated therapeutic diagnostic applications. distribution have strong influence on their behaviour vivo , including extravasation efficiency, circulation time, response ultrasound stimulation. Thus, it is desirable identify ways tailor during manufacturing. In this study phospholipid-coated NDs, comprising perfluoro-n-pentane (PFP) core stabilised by DSPC/PEG40s (1,2-distearoyl- sn -glycero-3-phosphocholine polyoxyethylene(40)stearate, 9:1 molar ratio) shell, produced phosphate-buffered saline (PBS) sonication. effect following production-related parameters was investigated: concentration, power duration sonication, incorporation fluorescent dye. stability also assessed both °C. When pulse 6 s 15% duty cycle employed, increasing from 5% v/v PBS resulted diameter 215.8 ± 16.8 nm 408.9 171.2 nm. An 48 72 W (with 10% PBS) 354.6 127.2 315.0 100.5 20 40 (using pulsed 30% cycle) did not result significant change (in range 278–314 nm); however, when increased 60 s, average reduced 249.7 9.7 nm, which presented significantly lower standard deviation compared other experimental conditions investigated (i.e., vs. > 49.4 nm). addition dye DiI different ratios affect distribution. up days min; some evidence ND-to-MB phase transition observed after min Finally, into MBs demonstrated using flow phantom under exposure (ultrasound frequency: 0.5 acoustic pressure: MPa, repetition 100 Hz).