Controlled thermal-sensitive liposomes release on a disposable microfluidic device.

Abstract

High intensity focused ultrasound (HIFU) triggered drug release as one of promising approaches for local drug delivery is gaining more attention as ultrasound allows the deposition of the thermal and mechanical energies to a specific localized region in a noninvasive manner. Release of encapsulated drugs from a nano-carrier such as liposome could further achieve a higher local drug concentration and reduce the toxicity effects under the stimulus of temperature elevation. This paper presents a micro HIFU (MHIFU) microfluidic device to enable mimic the bulky HIFU transmission system without the need of high power consumption and control the release of low temperature-sensitive liposomes (LTSL). Moreover, by adjusting the input signal, the temperature can be elevated and maintained at 37°C, 42°C and 50°C precisely with the error of ±0.3°C. The flow cytometry results show that HIFU-mediated drug delivery lead to an increase in uptake compared to water incubation-induced drug release at 42°C. Microfluidic technology may offer a promising alternative method for investigation of the complex dynamics between ultrasound and organisms in an ultramicroscopic manner.