Apparatuses and methods for operating a digital microfluidic device

A method for performing NGS library preparation on a digital microfluidic (DMF) device, comprising:

• a) loading a sample, a magnetic bead solution, a washing buffer, an elution buffer, an Adapter ligation reagent, an ER/AT (End Repair and A-Tailing) reagent, a fragmentation reagent, and a PCR reagent into a sample reservoir on the DMF device;
• b) dispensing a sample droplet from the sample reservoir and moving it to an electrode area on the DMF device;
• c) dispensing a fragmentation reagent droplet and merging it with the sample droplet for enzymatic fragmentation reactions at the electrode area on the DMF device;
• d) dispensing an ER/AT reagent droplet and merging it with a mixed sample droplet in b) or c) for the ER/AT reactions at the electrode area on the DMF device;
• e) dispensing an Adapter ligation reagent droplet and merging it with a mixed sample droplet in d) for the Adapter ligation reactions at the electrode area on the DMF device;
• f) dispensing a magnet bead droplet and merging it with a mixed sample droplet in e) at the electrode area on the DMF device for DNA/RNA capturing;
• g) using a magnetic field to focus the magnet beads in a mixed sample droplet in f) and move the focused magnet beads to a washing buffer reservoir;
• h) releasing the magnetic field and letting the magnet beads disperse in the washing buffer reservoir;
• i) applying a second magnetic field to focus the magnet beads in the washing buffer reservoir;
• j) using the second magnetic field to move the focused magnet beads to an elution buffer reservoir;
• k) releasing the second magnetic field and letting the magnet beads disperse in a fourth reagent reservoir;
• l) applying another magnetic field to focus the magnet beads in the fourth reagent reservoir;
• m) using the other magnetic field to move the focused magnet beads to the electrode area on the DMF device;
• n) dispensing a droplet from the elution buffer reservoir for further processing;
• o) an apparatus comprising:
• i. a voltage control module to provide electric signals to the DMF device for the manipulation of the liquids/droplets on the DMF device;
• and
• ii. a magnet control module to move at least one magnet in at least two directions vertically and horizontally.