TY - JOUR
T1 - Mechanical Division of Cell-Sized Liposomes
AU - Deshpande, Siddharth
AU - Spoelstra, Willem Kasper
AU - Van Doorn, Marleen
AU - Kerssemakers, Jacob
AU - Dekker, Cees
PY - 2018
Y1 - 2018
N2 - Liposomes, self-assembled vesicles with a lipid-bilayer boundary similar to cell membranes, are extensively used in both fundamental and applied sciences. Manipulation of their physical properties, such as growth and division, may significantly expand their use as model systems in cellular and synthetic biology. Several approaches have been explored to controllably divide liposomes, such as shape transformation through temperature cycling, incorporation of additional lipids, and the encapsulation of protein division machinery. However, so far, these methods lacked control, exhibited low efficiency, and yielded asymmetric division in terms of volume or lipid composition. Here, we present a microfluidics-based strategy to realize mechanical division of cell-sized (∼6 μm) liposomes. We use octanol-assisted liposome assembly (OLA) to produce liposomes on chip, which are subsequently flowed against the sharp edge of a wedge-shaped splitter. Upon encountering such a Y-shaped bifurcation, the liposomes are deformed and, remarkably, are able to divide into two stable daughter liposomes in just a few milliseconds. The probability of successful division is found to critically depend on the surface area-to-volume ratio of the mother liposome, which can be tuned through osmotic pressure, and to strongly correlate to the mother liposome size for given microchannel dimensions. The division process is highly symmetric (∼3% size variation between the daughter liposomes) and is accompanied by a low leakage. This mechanical division of liposomes may constitute a valuable step to establish a growth-division cycle of synthetic cells.
AB - Liposomes, self-assembled vesicles with a lipid-bilayer boundary similar to cell membranes, are extensively used in both fundamental and applied sciences. Manipulation of their physical properties, such as growth and division, may significantly expand their use as model systems in cellular and synthetic biology. Several approaches have been explored to controllably divide liposomes, such as shape transformation through temperature cycling, incorporation of additional lipids, and the encapsulation of protein division machinery. However, so far, these methods lacked control, exhibited low efficiency, and yielded asymmetric division in terms of volume or lipid composition. Here, we present a microfluidics-based strategy to realize mechanical division of cell-sized (∼6 μm) liposomes. We use octanol-assisted liposome assembly (OLA) to produce liposomes on chip, which are subsequently flowed against the sharp edge of a wedge-shaped splitter. Upon encountering such a Y-shaped bifurcation, the liposomes are deformed and, remarkably, are able to divide into two stable daughter liposomes in just a few milliseconds. The probability of successful division is found to critically depend on the surface area-to-volume ratio of the mother liposome, which can be tuned through osmotic pressure, and to strongly correlate to the mother liposome size for given microchannel dimensions. The division process is highly symmetric (∼3% size variation between the daughter liposomes) and is accompanied by a low leakage. This mechanical division of liposomes may constitute a valuable step to establish a growth-division cycle of synthetic cells.
KW - liposomes
KW - membrane biophysics
KW - microfluidics
KW - octanol-assisted liposome assembly
KW - synthetic biology
KW - Synthetic cell division
UR - http://resolver.tudelft.nl/uuid:3cd4a3bc-d9ea-4c04-95e3-176fff92e3a1
UR - http://www.scopus.com/inward/record.url?scp=85044508243&partnerID=8YFLogxK
U2 - 10.1021/acsnano.7b08411
DO - 10.1021/acsnano.7b08411
M3 - Article
AN - SCOPUS:85044508243
SN - 1936-0851
VL - 12
SP - 2560
EP - 2568
JO - ACS Nano
JF - ACS Nano
IS - 3
ER -