Generation of Monodisperse Microbubbles with a Controlled Size of Less Than 10 µm at a Generation Rate on the Order of 10⁵ Bubbles/s in Glass Capillary Microfluidic Devices

Abstract

Inexpensive glass capillary micro uidic devices with co-ow geometry were prepared to generate highly monodispersed microbubbles with a controlled size of less than 10 µm for medical applications. In the analysis, the dimensions of the injection and collection capillaries were decreased, and the gas pressure and liquid phase ow rate were increased to their respective limits. The diameter of the monodisperse microbubbles (having a coe cient of variation of less than 1.5%) could be controlled within the range of 2.4-9.2 µm, while maintaining a generation rate on the order of 10 5 bubbles/s by adjusting the inner tip diameter of the injection capillary and the liquid phase ow rate. The inner diameter of the collection capillary was 30 µm, and the gas pressure was 0.50 MPa.

Development of a Microfluidic Formatted Ultrasound‐Controlled Monodisperse Lipid Vesicles' Hydrogel Dressing Combined with Ultrasound for Transdermal Drug Delivery System

“…The use of the microfluidic chip can achieve high drug encapsulation efficiency and quantitative encapsulation of ultrasonic response materials, control the size and uniformity of the lipid vesicles, and evenly mix the lipid vesicles and hydrogel to prepare the required thickness of dressings. [37,38] It can solve the problems of traditional lipid vesicle preparation methods that result in wide particle size distribution, significant shape differences, unclear encapsulation, low encapsulation efficiency, and poor preparation repeatability. [39,40] Compared with conventional hydrogel dressings, such lipid vesicles are uniformly dispersed in the dressing as drug carriers, can solve the problems of uncontrollable sudden release, biological toxicity, and difficult penetration of water-soluble drugs, and has good biocompatibility.…”