Investigating The Effects Of Silk Fibroin On Ultrasound-Mediated Ultrafine Bubble Drug Transport And Delivery System

Abstract

Ultrafine bubbles with ultrasound stimuli have recently gained immense attention in developing drug delivery systems. However, investigations into their stability and the factors influencing this aspect were much at the infant stage. This study aimed to utilize silk fibroin (SF), a biocompatible protein extracted from Bombyx mori silkworm, in conjugation with polyethylene glycol 400 (PEG-400), to stabilize the ultrafine bubble drug loading and releasing system. Light scattering laser imaging was employed to inspect SF and PEG effects on the system stability. In addition, fluorescent laser imaging and optical absorbance measurement were also carried out, assessing these additives’ role in drug encapsulating and releasing process. The results confirmed the enhanced bubble stability by the introduction of both SF and PEG into the drug carrier system. In addition, although drug loading and releasing efficiencies were not significantly increased, these additives still provided an encapsulation capacity of more than 80% and a released drug content up to 50% after the ultrasound application.