US 12,330,155 B2
Method for isolating extracellular vesicles
Ji Yoon Kang, Seoul (KR); Bo Hoon Han, Seoul (KR); You Hee Heo, Seoul (KR); and Kyeong Sik Shin, Seoul (KR)
Assigned to KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed by KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed on Nov. 13, 2019, as Appl. No. 16/682,865.
Claims priority of application No. 10-2018-0164590 (KR), filed on Dec. 18, 2018.
Prior Publication US 2020/0188918 A1, Jun. 18, 2020
Int. Cl. G01N 1/34 (2006.01); B01L 3/00 (2006.01)
CPC B01L 3/502761 (2013.01) [G01N 1/34 (2013.01); B01L 2200/0668 (2013.01); B01L 2300/0861 (2013.01)] 5 Claims
 
1. A method for isolating extracellular vesicles from a sample containing the extracellular vesicles and proteins, said method comprising sequentially:
preparing a microfluidic chip in which a microfluidic channel whose length is 18 to 30 cm is formed and (i) three inlets comprising an upper inlet, an intermediate inlet and a lower inlet and (ii) three outlets comprising an upper outlet connected to the upper inlet, an intermediate outlet connected to the intermediate inlet, and a lower outlet connected to the lower inlet are formed at both ends of the channel, respectively;
injecting a first aqueous solution into the upper inlet and the lower inlet of the microfluidic chip to form a first microfluid and a second aqueous solution into the intermediate inlet of the microfluidic chip to form a second microfluid;
injecting a sample containing extracellular vesicles and proteins into the intermediate inlet of the microfluidic chip; and
recovering the second microfluid containing extracellular vesicles from the intermediate outlet,
wherein the first aqueous solution is an aqueous solution in which at least one first solute selected from the group consisting of polyethylene glycol, polyvinylpyrrolidone, and polyvinyl alcohol is dissolved in water, and the second aqueous solution is an aqueous solution in which at least one second solute selected from the group consisting of ethylene oxide propylene oxide (EOPO), dextran, levan, poly(vinyl methyl ethyl ether), ammonium sulfate, sodium sulfate, magnesium sulfate, potassium phosphate and sodium carbonate is dissolved in water,
wherein the first microfluid and the second microfluid are not mixed with each other due to their poor compatibility with each other, and thus the first microfluid forms an upper phase and a lower phase and the second microfluid forms an intermediate phase in the microfluidic channel, and
wherein the sample flows in the intermediate phase and the proteins are diffused to the upper phase and the lower phase but the diffusion of extracellular vesicles to the upper phase and the lower phase is minimized.