| dc.description.abstract | In recent years, ultrasound-guided delivery of drug loaded on extremely small
carriers has become one of the most conspicuous trends in improvement of drug
delivery. Ultrasound has often been used in combination with bubbles with
diameter smaller than sub-micron, referred as ultrafine bubbles, to amplify the
biophysical effects of the ultrasonic field. It is thus becoming increasingly
important to understand the factors affecting the formation and properties of
ultrafine bubbles in order to use them as an effective material, especially for strict
medical applications. This study investigates ultrafine bubbles formed in
electrolytes solution incorporating with ultrasound for drug loading and release.
The role of electrolytes in inhibition of bubble coalescence has been examined by
a series of experiment on the coalescence behavior of bubbles in neat water in
comparison with that in 154 mM sodium chloride solution after generation and
during a three-day storage period. Since the electrolyte concentration under
studied mimics the physiological salt concentration in human blood, the insights
brought by our study will be of great significance in laying the foundation for the
utilization of ultrafine gas bubbles in drug delivery. Our laser scattering and
contact angle measurements showed that nanobubbles formed in neat water
mostly vanished after one day of storage; while those formed in salt solution
remained mostly stable during three days of storage. Additionally, successful
encapsulation of quercetin to ultrafine bubbles has been observed. The release of
bubble-loaded quercetin by application of the high frequency acoustic wave has
also been tracked; the result indicated that under the influence of high frequency
acoustic wave, the ultrafine bubbles vibrated and liberated the drug.
Keywords:
Ultrafine bubbles
Electrolytes
Drug loading
Ultrasound | en_US |
