On-chip density-based purification of liposomes

On-chip density-based purification of liposomes

Deshpande, S.R. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)
Birnie, A.T.F. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)
Dekker, C. (TU Delft BN/Cees Dekker Lab; Kavli institute of nanoscience Delft)

2017-05-01

Due to their cell membrane-mimicking properties, liposomes have served as a versatile research tool in science, from membrane biophysics and drug delivery systems to bottom-up synthetic cells. We recently reported a novel microfluidic method, Octanol-assisted Liposome Assembly (OLA), to form cell-sized, monodisperse, unilamellar liposomes with excellent encapsulation efficiency. Although OLA provides crucial advantages over alternative methods, it suffers from the presence of 1-octanol droplets, an inevitable by-product of the production process. These droplets can adversely affect the system regarding liposome stability, channel clogging, and imaging quality. In this paper, we report a density-based technique to separate the liposomes from droplets, integrated on the same chip. We show that this method can yield highly pure (>95%) liposome samples. We also present data showing that a variety of other separation techniques (based on size or relative permittivity) were unsuccessful. Our density-based separation approach favourably decouples the production and separation module, thus allowing freshly prepared liposomes to be used for downstream on-chip experimentation. This simple separation technique will make OLA a more versatile and widely applicable tool.

http://resolver.tudelft.nl/uuid:383c4616-0fb6-4313-a49f-7182557a61e5

https://doi.org/10.1063/1.4983174

2018-05-01

1932-1058

Biomicrofluidics, 11 (3), 1-13

Institutional Repository

journal article

© 2017 S.R. Deshpande, A.T.F. Birnie, C. Dekker