Ryan Fobel edited this page Feb 20, 2018 · 44 revisions

DropBot v3 User Guide

Table of Contents

DropBot DB3-120 kit

You should have received the following items with your DropBot kit (see here for a larger image):

  1. DropBot DB3-120 instrument
  2. +12V power supply
  3. Test board
  4. USB A/B cable
  5. 3x DMF chips
  6. Device spacer
  7. Webcam
  8. Webcam holder
  9. Test tube containing 0.1 M NaCl + 0.1% Tetronic 90R4

Install MicroDrop

MicroDrop is a Windows app for programming and controlling the DropBot and the latest release can be downloaded here.

MicroDrop currently supports Windows 7/8/10.

Note: If you are running Windows 7, you will also need to install this driver before connecting the DropBot.

Connect DropBot

  1. Plug +12V power supply into wall outlet.
  2. Connect +12V power supply to DropBot.
  3. Connect USB cable between PC and DropBot.

DropBot power and USB

Run the on-board hardware diagnostic tests

Once you have MicroDrop installed and have connected the DropBot, the next thing you will want to do is test that your hardware arrived in a working state:

  1. Launch MicroDrop from the Windows Start menu.
  2. From the Tools\DropBot menu, select Run all on-board self-tests.

Note: If you have any trouble connecting to the DropBot, please see the Troubleshooting guide.

The software will pop up a wizard showing you how to insert the test board into your DropBot. These tests confirm that:

  1. The high-voltage source is working.
  2. The feedback-sensing circuit is working.
  3. There are no short-circuits on any of the actuation channels.
  4. All actuation channels are functional.

See below for an example report:

Example test report

Attach the Webcam

Attach the webcam to the DropBot as shown below:

Webcam holder installation

Note: For (optional) advanced control over webcam settings (e.g., fixed focus), download the Logitech Webcam Software from the Logitech C920 support page.

Insert a DMF chip

The following steps are illustrated in the figure below (see here for a larger image):

  1. Pick up DMF chip by edges, being careful not to touch the surface.
  2. Insert DMF chip into front of DropBot, and;
  3. ...push forward until it hits the back of the chip guide.
  4. Insert device spacer under the chip guide surface.
  5. Push device spacer in as far as possible.

Align webcam video to device drawing

See this screencast demonstrating how to register the webcam video to align with the device drawing in the DMF device user interface.

Load liquid onto the chip

To load liquid on the DMF chip:

  1. Enable realtime mode. This allows you to control the actuation state of electrodes by left-clicking on electrodes in the device view.
    Enable realtime mode
  2. Actuate a reservoir electrode using the MicroDrop software by left-clicking on it with your mouse.
    Load liquid screenshot
  3. Manually pipette ~6 uL of liquid at the edge of the top plate over the reservoir electrode.
    Load liquid onto the chip

Note: Liquids must have a sufficiently low surface tension to be loaded into reservoirs (e.g., the surface tension of pure water is too high to be drawn between the two hydrophobic plates). You can lower surface tension by adding surfactants (e.g., Tetronic 90R4). Reducing the surface tension also makes it easier to dispense/split drops.

Dispense, move, mix, and split droplets

Try out the basic droplet operations (dispense, move, mix, and split) by following along with this video playlist.

DMF chip specifications and sample mask

The DropBot DB3-120 kit includes sample DMF chips with a 90-pin electrode array configuration.

Sci-Bots 90-pin array v3

More of these chips are available for sale from Sci-Bots (please contact for a quote).

Note: custom chips may also be used with the DropBot DB3-120 system. Please see the DropBot DB3-120 chips specifications for more information.