Bio-repository Automationfor Efficient Long-term Frozen Storage

Background

Bio-repository is the storage of biological specimens for long periods of time. A biological sample, such as blood, is taken in a relatively large vial of about 4 mL. To help preserve this sample for a long period of time it must be frozen. When it is necessary to access a small amount of the sample, about 0.25 mL, the entire sample must be thawed, risking its quality. Therefore, it is better for the sample, and more convenient for the operator, if the sample is first distributed into smaller tubes, then frozen and stored. The process of filling the smaller tubes can be tedious and difficult. An automated robot, like the Beckman Biomek 1000, can achieve this with speed, accuracy, and reproducibility. An unused Biomek was restored and evaluated as a possible addition to the Integrative Perinatal Research Center at Michigan State University.

How the Biomek 1000 Functions

The Biomek has a tablet that holds the liquid sample and the mini-tubes into which the sample will be distributed. The tablet moves left to right while the Biomek’s arm moves up and down on an elevator shaft. A pod moves front to back on the arm to complete the range of motion. The pod picks up and holds a liquid handling tool. Stepper motors are used to provide this motion and activate the tool’s internal syringe. The motors are given commands from the electronic interface unit (EIU) which translates messages from the computer. The operator uses the computer to tell the EIU the configuration of the tablet and what tasks to perform. The tool is designed to pick up a sterile plastic pipette tip, which will directly contact the sample. After this tip is lowered into the sample, the syringe is pulled up, drawing the specified amount of liquid into the tip. The tool is then moved to the destination mini-tube and the liquid is pushed out. This process is repeated for each mini-tube to be filled. The mini-tube tray is then ready for storage.

Conclusions•The Beckman Biomek 1000, though capable of all desired tasks, is too large for use in a small MSU lab and is capable of doing much more than what is needed.

•A smaller and simpler autonomous robot can be developed to perform only the desired tasks. This robot would also use stepper motors, but would be commanded by a microcontroller.

Michael Balck, Undergraduate Student

Dr. Ranjan Mukherjee and Dr. Clark Radcliffe, Faculty

Elevator

Mini-tube Tray

4 mL Vial

TabletTool

EIU

Pod

Arm

Tips

The Beckman Biomek 1000

Sample in 4 mL tube is

taken to the lab

Automation device distributes the sample into mini-tubes

The Bio-repository Process

4 mL tube is placed into a automation device

with the mini-tube tray

Mini-tube tray is stored in a freezer