Microfluidic purification device

A microfluidic purification device, comprising:

• a first stage filter, configured to receive an input solution and output an output solution;
• a filter assembly, configured to receive the output solution from the first stage filter and purify the output solution into multiple exosomes, and comprising:
• a first inlet valve, connected with the first stage filter;
• a first input chamber, connected with the first inlet valve;
• a first micro-electromechanical system (MEMS) filter, attached to the first input chamber;
• an output chamber, the first MEMS filter located between the first input chamber and the output chamber;
• and
• a first outlet valve, connected with the output chamber;
• an ultrasound vibrator, disposed under the filter assembly;
• and
• a controller, electrically connected with the ultrasound vibrator, the first inlet valve, and the first outlet valve, wherein the controller is configured to control the ultrasound vibrator to perform an intermittent vibration operation and to independently switch the first inlet valve and the first outlet valve between an open state and a closed state;
• wherein the first MEMS filter comprises a funnel structure, and an output hole of the funnel structure is smaller than an input hole of the funnel structure;
• wherein the input hole is arranged at a position closer to the first input chamber than the output chamber, the output hole is arranged at a position closer to the output chamber than the first input chamber;
• wherein a size of the output hole is larger than sizes of the multiple exosomes;
• wherein the output hole has a constant first diameter, and the input hole has a V-shaped cross-section with a second diameter that gradually increases from a junction with the output hole toward the first input chamber;
• and
• wherein the controller is configured such that:
• the output solution enters the first input chamber while the first inlet valve is in the open state and the first outlet valve is in the closed state;
• the first inlet valve transition from the open state to the closed state upon the first input chamber being filled;
• the ultrasound vibrator performs the intermittent vibration operation while both the first inlet valve and the first outlet valve are in the closed state;
• and
• after completion of the intermittent vibration operation, the first outlet valve transitions from the close state to the open state to drain out the exosomes.